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  • CLASSES

    Influenza Vaccines

    DEA CLASS

    Rx

    DESCRIPTION

    Intranasal, live, attenuated, influenza vaccine (LAIV)
    Only approved for certain people aged 2 to 49 years
    Stimulates localized mucosal antibody formation; unknown duration of influenza vaccine virus replication and shedding.

    COMMON BRAND NAMES

    FluMist

    HOW SUPPLIED

    Influenza A Virus H1N1 antigen, Influenza A Virus H3N2 antigen, Influenza B Virus Brisbane 60/2008 antigen, Influenza B Virus Phuket 3073/2013 antigen Nasal Spray Met

    DOSAGE & INDICATIONS

    For annual seasonal influenza prophylaxis in healthy persons aged 2 to 49 years.
    NOTE: The intranasal influenza vaccine, live may not be appropriate for pregnant women or for patients with immunosuppression, asthma, or egg allergy. The inactivated vaccine (see separate monograph) is preferred over the live, attenuated vaccine for immunizing household members, health-care workers, and others who have close contact with severely immunosuppressed persons during periods when such persons require care in a protected environment. As a precautionary measure, recipients of the live, attenuated vaccine should avoid close contact with severely immunosuppressed persons for 7 days after vaccination. Live influenza virus may be secreted by the vaccinated individual for at least 21 days.
    NOTE: Two doses of influenza vaccine in the initial year that the vaccine is given are recommended for children less than 9 years of age; 1 dose would be given for all subsequent seasons. The American Academy of Pediatrics recommends children up to 9 years of age who received only one dose the first time they are vaccinated receive 2 doses the following influenza season. The Advisory Committee on Immunization Practices (ACIP) recommends that children aged 6 months through 8 years who have previously received at least 2 doses of trivalent or quadrivalent influenza vaccine before July 1, 2015, receive only 1 dose for 2015 to 2016. The two previous doses need not have been given during the same season or consecutive seasons.
    Intranasal dosage (FluMist Trivalent and Quadrivalent)
    Adults, Adolescents, and Children 9 to 49 years

    Give 1 dose (roughly 0.1 mL into each nostril, for a total of 0.2 mL) intranasally prior to the start of each flu season (vaccine usually given in early fall).

    Children 2 to 8 years

    For previously vaccinated children, give 1 dose (roughly 0.1 mL into each nostril, for a total of 0.2 mL) intranasally prior to the start of each flu season (vaccine usually given in early fall). For previously unvaccinated children, give 1 dose (roughly 0.1 mL into each nostril, for a total of 0.2 mL) intranasally prior to the start of the flu season and 1 dose given at least 4 weeks later. NOTE: Children aged 2 to 8 years who are receiving the vaccine for the first time should be vaccinated in October or earlier; this allows the proper booster dose to be completed at least 4 weeks after the first dose to complete immunization.

    MAXIMUM DOSAGE

    Adults

    < 50 years: 0.2 mL/dose intranasally.
    >= 50 years: Safety and efficacy have not been established.

    Geriatric

    Safety and efficacy have not been established.

    Adolescents

    0.2 ml/dose intranasally.

    Children

    >= 2 years: 0.2 mL/dose intranasally.
    < 2 years: Safety and efficacy have not been established.

    Infants

    Safety and efficacy have not been established.

    DOSING CONSIDERATIONS

    Hepatic Impairment

    Specific guidelines for dosage adjustments in hepatic impairment are not available; it appears that no dosage adjustments are needed.

    Renal Impairment

    Specific guidelines for dosage adjustments in renal impairment are not available; it appears that no dosage adjustments are needed.

    ADMINISTRATION

     
    Health care professionals administering vaccines should take appropriate precautions to prevent allergic reactions in vaccine recipients. Ask potential vaccine recipients about allergies, especially to eggs. Epinephrine injection or a comparable treatment must be readily available.
    Prior to the administration of the intranasal influenza vaccine, health care personnel should inform the patient, parent, guardian, or responsible adult of the vaccine's benefits and risks. This should include the provision of the vaccine information statement from the manufacturer.
    According to U.S. federal laws, the health care provider must record in the patient's permanent record: the manufacturer, lot number, date of administration, and the name and address of the person administering the vaccine.

    Topical Administration
    Other Topical Formulations

    Intranasal Administration
    Administer intranasally only. Do not administer parenterally.
    Visually inspect the vaccine before administration. The vaccine should be colorless to a pale yellow that is clear to slightly cloudy.
    Check the expiration date on the sprayer label.
    Remove the rubber tip protector. Do not remove the dose-divide clip at the other end of the sprayer.
    The vaccine recipient needs to be in the upright position. Place the sprayer tip just inside the nostril and depress the plunger as rapidly as possible to administer half of the dose (0.1 mL). Remove the dose-divider clip and spray the remaining dose (0.1 mL) into the other nostril. The total dose will be 0.2 mL.
    Active inhalation (i.e., sniffing) is not required by the patient during administration.
    If the vaccine recipient sneezes after administration, do not repeat the dose.
    Each 0.2 mL sprayer is for single-use only. Throw away the used nasal sprayer in an approved biohazard waste container.
    Storage: Store in a refrigerator between 2 to 8 degrees C (35 to 46 degrees F) upon receipt. Do not freeze. Keep sprayer in carton to protect from light. A single temperature excursion up to 25 degrees C for 12 hours has been shown to have no adverse impact on the vaccine. After a temperature excursion, the vaccine should be returned immediately to the recommended storage condition (2 to 8 degrees C) and used as soon as feasible. Subsequent excursions are not permitted.

    STORAGE

    FluMist:
    - Do not freeze
    - Protect from light
    - Refrigerate (between 36 and 46 degrees F)
    - Store in carton

    CONTRAINDICATIONS / PRECAUTIONS

    General Information

    Prior to the administration of Flumist, the health care personnel should inform the patient, parent, guardian, or responsible adult of the vaccine's benefits and risks. This should include the provision of the vaccine information statement from the manufacturer. The responsible adult should report any adverse reaction following vaccine administration to the health care provider. The U.S. Department of Health and Human Services has established a Vaccine Adverse Event Reporting System (VAERS) to accept all reports of suspected adverse events after the administration of any vaccine; the vaccine manufacturer also requests contact. This includes, but is not limited to, the reporting of events required by the National Childhood Vaccine Injury Act of 1986. The toll-free number for VAERS is (800) 822—7967.

    Fever, infection, respiratory infection

    Intranasal influenza vaccine (FluMist) use should be postponed for at least 72 hours in patients with acute fever or infection, such as a respiratory infection. Administration of the intranasal influenza vaccine to a person suspected of having influenza (the 'flu') is not recommended. The vaccine will not attenuate the duration or severity of a current influenza infection. Also, the vaccine could worsen a patient's clinical status, as FluMist is a live attenuated vaccine. Allergic rhinitis does not preclude intranasal influenza vaccine administration. There are no data regarding concurrent intranasal corticosteroid administration and the use of intranasal influenza vaccine.

    Aminoglycoside hypersensitivity, egg hypersensitivity, gelatin hypersensitivity

    FluMist is contraindicated in individuals with life-threatening reactions to previous influenza vaccinations or with a history of hypersensitivity, especially anaphylactic reactions, to eggs or egg proteins. Patients should not receive the intranasal influenza vaccine (FluMist) if they have experienced egg hypersensitivity or chick embryo protein hypersensitivity that has resulted in any of the following manifestations: urticaria, swelling of the lips or tongue (angioedema), or acute respiratory distress or collapse. Persons who have documented immunoglobulin E (IgE)-mediated hypersensitivity to eggs (including those who have had occupational reactive airways disease or other allergic responses due to exposure to egg protein) are at increased risk for reactions from influenza vaccine. Patients with allergies to chicken or chicken feathers generally should be able to be vaccinated. The ACIP recommendations for administering the influenza vaccine to persons with egg hypersensitivity are as follows: (1) persons who can eat lightly cooked eggs without reaction may receive the vaccine per usual protocol; (2) persons with only hives (urticaria) to egg exposure should receive a trivalent inactivated vaccine (TIV, see Influenza Virus Vaccine monograph) instead of the FluMist live-attenuated intranasal influenza vaccine (LAIV); (3) persons with severe reactions to eggs (e.g., angioedema, respiratory distress, lightheadedness, recurrent emesis, or required epinephrine or medical attention within minute of egg exposure) and persons suspected of being egg-allergic based on allergy testing but without a known exposure to eggs should receive Flublok (a trivalent inactivated vaccine) or be referred to physician with expertise in managing allergic conditions for assessment. Each 0.2 mL FluMist dose contains 2 mg/dose hydrolyzed porcine gelatin, 2.42 mg/dose arginine, and < 0.015 mcg/mL gentamicin sulfate. Patients with gelatin hypersensitivity, arginine hypersensitivity, or aminoglycoside hypersensitivity may be inappropriate candidates for FluMist receipt. As with any biologic product, the prescriber or health care professional should take precautions to prevent allergic reactions by asking the intended recipient about any allergies, especially to eggs. The health care professional should have immediate availability of epinephrine (1:1000) injection and other agents used in the treatment of severe anaphylaxis in the event of a serious allergic reaction to the intranasal influenza vaccine.

    Pregnancy

    The intranasal influenza vaccine (FluMist) is a pregnancy risk category B drug. No adequate and well-controlled studies have been conducted in pregnant women and the ability of the vaccine to cause fetal harm or affect reproductive capacity is unknown. The manufacturer recommends administration to pregnant women only if clearly needed. According to the Advisory Committee on Immunization Practices (ACIP), administration of live vaccines to pregnant women pose a theoretical risk to the fetus and, therefore, should be avoided. However, because pregnancy may increase the risk of serious medical complications from influenza, the ACIP recommends that all women who are pregnant or will be pregnant (in any trimester) during influenza season be routinely vaccinated with an inactivated influenza virus vaccine (see Influenza Virus Vaccine monograph).  Many experts consider the inactivated influenza virus vaccine safe during any stage of pregnancy. However, because spontaneous abortion is common in the first trimester and unnecessary drug-exposures have traditionally been avoided during this time, some experts prefer waiting until the second trimester to vaccinate.

    Breast-feeding

    Data are limited regarding use of the intranasal influenza vaccine (FluMist) during breast-feeding and its' excretion in human milk is unknown. The manufacturer recommends caution when administering to nursing mothers; however according to the Advisory Committee on Immunization Practices (ACIP), live virus vaccines do not affect the safety of breast-feeding. Health care providers are advised that, although attenuated, the potential of transmitting live viruses to the infant through breast milk exists. If vaccination of a lactating woman is desirable, use of an inactivated influenza virus vaccine may be an appropriate alternative (see Influenza Virus Vaccine monograph). Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition. If a breast-feeding infant experiences an adverse effect related to a maternally administered drug, health care providers are encouraged to report the adverse effect to the FDA.

    Agammaglobulinemia, cardiac disease, chemotherapy, chronic obstructive pulmonary disease (COPD), cystic fibrosis, diabetes mellitus, hemoglobinopathy, hepatic disease, hypogammaglobulinemia, immunosuppression, leukemia, lymphoma, neoplastic disease, radiation therapy, renal failure, severe combined immunodeficiency (SCID), sickle cell disease

    The intranasal influenza vaccine is a live vaccine, and live vaccines are contraindicated for use by patients with severe combined immunodeficiency (SCID) disease. Data supporting the safety and effectiveness of FluMist administration in patients with lesser degrees of immunosuppression are limited. No serious adverse reactions were reported one month after FluMist administration to 57 adults with HIV infection who had a median CD4 count of 541 cells/mm3; efficacy of the vaccine was not determined. Carefully consider the potential benefits and risks of the intranasal influenza vaccine (FluMist) for immunocompromised patients such as patients with hypogammaglobulinemia, agammaglobulinemia, or neoplastic disease (e.g., leukemia or lymphoma). Receipt of immunosuppressives, chemotherapy, or radiation therapy can also lead to immunosuppression. In addition to immunocompromised patients, the safety of FluMist in individuals with underlying medical conditions that may predispose them to complications after wild-type influenza infection has not been established; only administer FluMist if the potential benefit outweighs the potential risk. Examples of conditions that may predispose to influenza complications include cardiac disease, pulmonary conditions (e.g., chronic obstructive pulmonary disease (COPD) and cystic fibrosis), diabetes mellitus, hemoglobinopathy (e.g., sickle cell disease), chronic hepatic disease, and renal failure. Practitioners should refer to the most recent CDC guidelines regarding vaccination of specific immunosuppressed patients.

    Acquired immunodeficiency syndrome (AIDS), human immunodeficiency virus (HIV) infection

    The efficacy of the intranasal influenza vaccine (FluMist) has not been established in patients with human immunodeficiency virus (HIV) infection or acquired immunodeficiency syndrome (AIDS). The live virus vaccine could cause serious influenza infection. However, among 57 adults with HIV and a median CD4 cell count of 541 cells/mm3, no serious adverse events were reported during the 4 weeks after vaccine receipt; the effectiveness of FluMist in preventing influenza illness was not evaluated. The CDC recommends immunization of HIV-infected individuals with the inactivated vaccine, as this measure is safe and may confer protection against influenza. Inactivated influenza vaccination should be offered to all patients with HIV infection.  One randomized, placebo controlled trial noted that the administration of influenza virus vaccine was highly effective in preventing hospitalization due to influenza in patients with HIV infection and was not associated with changes in viral load or CD4 counts (mean count 400 cells/mm3). However, because of the theoretical concern that increases in HIV plasma RNA following vaccination during pregnancy might increase the risk of perinatal transmission of HIV, providers may wish to defer vaccination for HIV-positive pregnant patients until after HAART is initiated.

    Asthma

    The intranasal influenza vaccine (FluMist) may be inappropriate for use in patients with a history of asthma or reactive airways disease. The safety of the product has not been established in this population. Also, in general, do not administer FluMist to any patient less than 5 years old with recurrent wheezing because of the potential for increased risk of wheezing after vaccination; weigh the potential benefit against the potential risk. In a placebo-controlled safety study, an increase in asthma events was observed among patients less than 5 years of age. Do not administer FluMist to patients with severe asthma or active wheezing because these individuals have not been studied in clinical trials. If vaccination of patients with wheezing or asthma is desirable, the inactivated influenza virus vaccine may be appropriate (see Influenza Virus Vaccine monograph).

    Geriatric

    FluMist is not indicated for use in geriatric patients; the vaccine is only indicated for patients 2—49 years of age. Further, the effectiveness of the vaccine was not demonstrated in a trial of 641 patients 50—64 years of age.

    Children, infants, neonates, Reye's syndrome

    Neonates, infants, and children < 2 years of age should not receive the live-attenuated influenza vaccine (FluMist). In clinical trials, an increased risk of wheezing, that required bronchodilator therapy or was associated with significant respiratory symptoms within 6 weeks of vaccination, and hospitalization (for any cause within 6 months) was observed among children < 2 years who received FluMist (5.9% and 4.2%, respectively) compared with those who received inactivated influenza vaccine (3.8% and 3.2%, respectively). The inactivated influenza virus vaccine should be used to vaccinate infants and children >= 6 months to 2 years of age. FluMist is contraindicated in children and adolescents up to 17 years of age receiving salicylate therapy (e.g., aspirin or aspirin-containing therapy). In addition, children < 5 years of age with recurrent wheezing may be at increased risk for wheezing after administration of the intranasal influenza vaccine. The intranasal influenza vaccine is a live vaccine, and thus could potentially result in influenza infection and in the development of Reye's syndrome in these patients.

    Guillain-Barre syndrome

    Carefully consider the potential benefits and risks of the intranasal influenza vaccine (FluMist) for patients who have developed Guillain-Barre syndrome (GBS) within 6 weeks of a previous influenza vaccination. Persons with a history of GBS have a substantially greater likelihood of subsequently developing GBS than persons without such a history. Thus, the likelihood of coincidentally developing GBS after influenza vaccination is expected to be greater among persons with a history of GBS than among persons with no history of it. It is not known if influenza vaccination is causally associated with this risk for recurrence of GBS. Nevertheless, the Advisory Committee on Immunization Practices (ACIP) recommends against influenza immunization in non-high risk patients who have developed GBS within 6 weeks of a previous influenza vaccination. However, for persons with a history of GBS who are at high risk for severe complications from influenza, the benefits of the influenza vaccination may justify the risks.

    Multiple sclerosis, neurological disease, neuromuscular disease, seizure disorder

    According to the Advisory Committee on Immunization Practices (ACIP), patients with a neurological disease (e.g., seizure disorder) or a neuromuscular disease (e.g., multiple sclerosis) are at increased risk for severe complications from influenza; however, use of the intranasal influenza vaccine (FluMist) in these patients is not recommended. Instead, consider administering an inactivated influenza virus vaccine to patients with neurologic/neuromuscular disorders..

    ADVERSE REACTIONS

    Severe

    pericarditis / Delayed / Incidence not known
    bronchospasm / Rapid / Incidence not known
    anaphylactoid reactions / Rapid / Incidence not known
    angioedema / Rapid / Incidence not known
    anaphylactic shock / Rapid / Incidence not known
    Guillain-Barre syndrome / Delayed / Incidence not known

    Moderate

    wheezing / Rapid / Incidence not known
    meningitis / Delayed / Incidence not known

    Mild

    nasal congestion / Early / 9.0-58.0
    rhinorrhea / Early / 44.0-58.0
    headache / Early / 3.0-40.0
    weakness / Early / 0-26.0
    anorexia / Delayed / 13.0-21.0
    irritability / Delayed / 12.0-21.0
    myalgia / Early / 2.0-17.0
    fever / Early / 7.0-16.0
    cough / Delayed / 0-14.0
    lethargy / Early / 6.0-14.0
    abdominal pain / Early / 2.0-12.0
    chills / Rapid / 2.0-9.0
    sinusitis / Delayed / 0-4.0
    sneezing / Early / 0-2.0
    diarrhea / Early / Incidence not known
    nausea / Early / Incidence not known
    urticaria / Rapid / Incidence not known
    vomiting / Early / Incidence not known
    rash (unspecified) / Early / Incidence not known

    DRUG INTERACTIONS

    Abatacept: (Severe) If possible, administer all needed vaccines before abatacept initiation. Live vaccines should not be given concurrently with abatacept or within 3 months of its discontinuation. The immune response of the immunocompromised patient to vaccines may be decreased and adjusted doses or boosters that are more frequent may be required. The immune response to an inactive vaccine may still be suboptimal. Live virus vaccines may induce the illness they are intended to prevent and are contraindicated for use during immunosuppressive treatment. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Abciximab: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Adalimumab: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system. (Major) It is not clear if adalimumab interferes with the effectiveness of influenza virus vaccine. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients receiving such therapies.
    Aldesleukin, IL-2: (Severe) Aldesleukin, IL-2 is associated with impaired neutrophil function. Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Alefacept: (Severe) The safety and efficacy of administering attenuated virus vaccines or live vaccines to patients receiving alefacept have not been studied. Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Alemtuzumab: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Alkylating agents: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Alpha interferons: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient, including those receiving Interferon therapy. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Altretamine: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Amantadine: (Major) The intranasal live attenuated influenza vaccine (LAIV) should not be administered within 2 weeks before or 48 hours after administration of amantadine, unless medically indicated. The concurrent use of amantadine with intranasal LAIV has not been evaluated. The concern about possible interference arises from the potential for antiviral drugs to inhibit replication of live vaccine virus. The trivalent inactivated influenza vaccine injection can be administered at any time relative to use of amantadine. Consult currently recommended guidance on the use of antiviral drugs against influenza.
    Anakinra: (Severe) No data are available on the effects of vaccination with live virus vaccines in patients receiving anakinra. Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Anthracyclines: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Antimetabolites: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Antithymocyte Globulin: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Antitumor antibiotics: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Arsenic Trioxide: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Azathioprine: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Basiliximab: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Belatacept: (Severe) Avoid the use of live vaccines such as the intranasal influenza vaccine; measles/mumps/rubella vaccines, MMR; Bacillus Calmette-Guerin Live, BCG; yellow fever vaccine; oral polio vaccine; varicella virus vaccine live; and TY21a typhoid vaccine during belatacept treatment. Further, inactive vaccine receipt may not illicit an acceptable response; belatacept may blunt the effectiveness of some immunizations. Consult the most current CDC guidances for vaccination recommendations.
    Belimumab: (Major) Live vaccines should not be given for 30 days before or concurrently with belimumab, as clinical safety has not been established. Because of its mechanism of action, belimumab may interfere with the response to immunizations. No data are available on the secondary transmission of infection from persons receiving live vaccines. Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Bevacizumab: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Bexarotene: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Bortezomib: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Brodalumab: (Major) Avoid administration of live vaccines to brodalumab recipients. Before initiation of brodalumab therapy, consider completion of all age appropriate vaccinations per current immunization guidelines. No data are available on the response to live or inactive vaccines in patients receiving brodalumab therapy.
    Busulfan: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Canakinumab: (Major) Do not administer live vaccines to a patient who is receiving canakinumab; other vaccination schedules should be complete as recommended prior to initiating canakinumab treatment. No data are available regarding the risk of secondary transmission of infection by live vaccines, and the efficacy and safety of live vaccines have not been established in patients receiving canakinumab. The immune response to vaccines or toxoids may be decreased, as canakinumab may interfere with normal immune response to new antigens. Limited data are available on the effectiveness of vaccination with inactivated antigens in patients receiving canakinumab. Because interleukin-1 blockade may interfere with immune response to infections, it is recommended that prior to initiation of therapy with canakinumab, adult and pediatric patients receive any recommended vaccination (including pneumococcal vaccine and inactivated influenza vaccines).
    Carbamazepine: (Minor) The elimination of some medications that are metabolized by cytochrome P-450, including carbamazepine, may be altered following administration of influenza virus vaccine. Reports concerning impaired drug clearance and possible toxicity are conflicting, and the clinical importance of the potential interaction is not clear.
    Carmustine, BCNU: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Certolizumab pegol: (Severe) Do not administer live vaccines concurrently with certolizumab. No data are available on the response to vaccinations or to the secondary transmission of infection by live vaccines in patients receiving certolizumab. Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Chlorambucil: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Clofarabine: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system
    Corticosteroids: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system. Children who are receiving high doses of systemic corticosteroids (i.e., greater than or equal to 2 mg/kg prednisone orally per day) for 2 weeks or more may be vaccinated after steroid therapy has been discontinued for at least 3 months in accordance with general recommendations for the use of live-virus vaccines. The CDC has stated that discontinuation of steroids for 1 month prior to varicella virus vaccine live administration may be sufficient. Budesonide may affect the immunogenicity of live vaccines. An open-label study examined the immune responsiveness to varicella vaccine in 243 pediatric asthma patients who were treated with budesonide inhalation suspension 0.251 mg daily (n = 151) or non-corticosteroid asthma therapy (n = 92). The percentage of patients developing a seroprotective antibody titer of at least 5 (gpELISA value) in response to the vaccination was slightly lower in patients treated with budesonide compared to patients treated with non-corticosteroid asthma therapy (85% vs. 90%). Even though no patient treated with budesonide inhalation suspension developed chicken pox because of vaccination, live-virus vaccines should not be given to individuals who are considered to be immunocompromised until more information is available.
    Cyclophosphamide: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Cyclosporine: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Dacarbazine, DTIC: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Dasatinib: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Denileukin Diftitox: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Dupilumab: (Major) Avoid administration of live vaccines to dupilumab recipients. Before initiation of dupilumab therapy, consider completion of all age appropriate vaccinations per current immunization guidelines. No data are available on the response to live vaccines in patients receiving dupilumab therapy.
    Efalizumab: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Estramustine: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Etanercept: (Severe) Etanercept has not been found to act as a general immunosuppressant; however, the patient's underlying disease state may result in the immunosuppression. Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune syste
    Fingolimod: (Severe) Do not administer live vaccines to a patient who is receiving fingolimod or has discontinued the drug in the last 2 months because of the risk of infection. No data are available regarding the risk of secondary transmission of infection by live vaccines, and the efficacy and safety of live vaccines have not been established in patients receiving fingolimod. Before fingolimod initiation, test patients without a history of chickenpox or without vaccination against varicella zoster virus (VZV) for antibodies to VZV. Consider VZV vaccination of antibody-negative patients before fingolimod initiation, and do not start fingolimod for 1 month to allow the full effect of vaccination to occur. In addition to the concerns with live virus vaccines, the immune response to inactive vaccines or toxoids may be decreased, as fingolimod may interfere with normal immune response to new antigens. No data are available on the effectiveness of vaccination with inactivated antigens in patients receiving fingolimod. Vaccination may be less effective during and for up to 2 months after fingolimod discontinuation. For example, as compared with the response of placebo recipients, the capacity to mount a skin delayed-type hypersensitivity reaction to Candida and to tetanus toxoid was decreased by approximately 30% among fingolimod 0.5 mg daily recipients. Further, in healthy patients, antigen-specific IgM titers were decreased by 25% in response to pneumococcal polysaccharide vaccine (PPV-23) immunization as compared with the response by placebo recipients. Similarly, IgG titers were decreased by 50% among fingolimod recipients as compared with placebo.
    Folate analogs: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Fosphenytoin: (Minor) Although influenza virus vaccine has been reported to inhibit the clearance of medications metabolized by cytochrome P-450 including phenytoin (or fosphenytoin), the reports concerning possible toxicity are conflicting. Most recent reports have noted no adverse clinical outcomes from the use of influenza virus vaccine in patients taking these medications; the use of these medications should not prohibit influenza immunization if indicated. Isolated reports of increased or decreased phenytoin serum concentrations secondary to the administration of influenza virus vaccine exist, but these interactions appear to be rare. Interactions, when they occur, are usually noted between 7 and 14 days post-vaccination. Although not routinely expected, it may be prudent to inform patients of how to recognize and manage the symptoms of phenytoin toxicity or the symptoms of decreased phenytoin efficacy after receiving flu vaccination.
    Gefitinib: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Golimumab: (Severe) Do not administer live vaccines to golimumab recipients. No data are available on the response to live vaccination or on the risk of infection or infection transmission after the administration. Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Guselkumab: (Major) Avoid use of live vaccines in patients being treated with guselkumab; no data are available regarding the risk of secondary transmission of infection by live vaccines in patients receiving guselkumab. In addition, guselkumab may decrease the vaccine-induced immune response. Before initiation of guselkumab therapy, consider completion of all age appropriate vaccinations per current immunization guidelines.
    Hydroxychloroquine: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Ibritumomab Tiuxetan: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Ifosfamide: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Imatinib: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Infliximab: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Ixabepilone: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Ixekizumab: (Major) Do not administer live vaccines to ixekizumab recipients. Before initiation of ixekizumab therapy, consider completion of all age appropriate vaccinations per current immunization guidelines. No data are available on the response to live or inactive vaccines in patients receiving Ixekizumab therapy.
    Lapatinib: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Leflunomide: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Lenalidomide: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Lomustine, CCNU: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Mechlorethamine, Nitrogen Mustard: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Mitotane: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Monoclonal antibodies: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Muromonab-CD3: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Natalizumab: (Severe) The immune response to vaccines or toxoids may be decreased in patients who receive natalizumab; however, no data are available. Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Natural Antineoplastics: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Nelarabine: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Nilotinib: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Ocrelizumab: (Major) Due to the lack of clinical information related to the safety and efficacy of vaccine administration during ocrelizumab use, concomitant vaccination with live vaccines or live-attenuated vaccines is not recommended. Withhold vaccination with live or live-attenuated virus vaccines to patients during ocrelizumab treatment and until B-cell repletion. Administer all vaccinations according to current vaccination guidelines and CDC recommendations at least 6 weeks before starting treatment with ocrelizumab. The ability to generate a primary or anamnestic humoral response to any vaccine following ocrelizumab has not been studied. ACIP recommends that patients receiving any vaccination during immunosuppressive therapy or in the 2 weeks prior to starting therapy should be considered unimmunized and should be revaccinated a minimum of 3 months after discontinuation of therapy. Passive immunoprophylaxis with immune globulins may be indicated for immunocompromised persons instead of, or in addition to, vaccination.
    Ofatumumab: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Palivizumab: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Phenytoin: (Minor) Although influenza virus vaccine has been reported to inhibit the clearance of medications metabolized by cytochrome P-450 including phenytoin, the reports concerning possible toxicity are conflicting. The use of these medications should not prohibit influenza immunization if indicated.
    Procarbazine: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Purine analogs: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Rilonacept: (Severe) Do not administer live vaccines to a patient who is receiving rilonacept. No data are available regarding the use of live vaccines during rilonacept treatment. Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Rituximab: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Rituximab; Hyaluronidase: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Sarilumab: (Major) Avoid concurrent use of live vaccines during treatment with sarilumab due to potentially increased risk of infections; clinical safety of live vaccines during sarilumab treatment has not been established. No data are available on the secondary transmission of infection from persons receiving live vaccines to patients receiving sarilumab. The interval between live vaccinations and initiation of sarilumab therapy should be in accordance with current vaccination guidelines regarding immunosuppressive agents.
    Secukinumab: (Major) Do not administer live vaccines to secukinumab recipients; no data are available regarding the risk of secondary transmission of infection by live vaccines in patients receiving secukinumab. Before initiation of secukinumab therapy, consider completion of all age appropriate vaccinations per current immunization guidelines. Secukinumab recipients may receive inactivated vaccines, but the immune response to vaccines or toxoids may be decreased. Similar antibody responses were seen when healthy individuals who received a single 150 mg dose of secukinumab 2 weeks before vaccination with a non-US approved group C meningococcal polysaccharide conjugate vaccine and a non-US approved inactivated seasonal influenza vaccine. The efficacy of meningococcal and influenza vaccines has not been evaluated in patients undergoing treatment with secukinumab.
    Sorafenib: (Major) Concomitant administration of immunosuppressives such as antineoplastic agents can decrease an individual's immunological response to live vaccines or can result in more extensive vaccine-associated adverse events. Refer to the most recent CDC guidelines regarding vaccination of immunosuppressed patients.
    Streptozocin: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Sunitinib: (Major) Concomitant administration of immunosuppressives such as antineoplastic agents can decrease an individual's immunological response to live vaccines or can result in more extensive vaccine-associated adverse events. Refer to the most recent CDC guidelines regarding vaccination of immunosuppressed patients.
    Taxanes: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Temozolomide: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Temsirolimus: (Severe) The use of live vaccines should be avoided during treatment with temsirolimus. Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Teriflunomide: (Major) Due to the lack of clinical information related to the safety and efficacy of vaccine administration during teriflunomide use, concomitant vaccination with live vaccines is not recommended. The long half-life of teriflunomide should be considered when contemplating administration of a live vaccine after stopping the medication if the teriflunomide drug elimination procedure has not been performed.
    Thalidomide: (Severe) No data are available on the response to vaccination with live vaccines or on the secondary transmission of infection by live vaccines in patients receiving thalidomide. Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Theophylline, Aminophylline: (Minor) Influenza virus vaccine has been reported to inhibit the clearance of medications metabolized by cytochrome P-450 including theophylline or aminophylline. The use of these medications should not prohibit influenza immunization if indicated. However, because an occasional predisposed patient may experience an increase in the effects of theophylline or aminophylline, monitoring for theophylline toxicity may be warranted; a temporary dosage adjustment may be needed if an interaction occurs.
    Thiotepa: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Tocilizumab: (Major) Avoid concurrent use of live vaccines during treatment with tocilizumab due to potentially increased risk of infections; clinical safety of live vaccines during tocilizumab treatment has not been established. No data are available on the secondary transmission of infection from persons receiving live vaccines to patients receiving tocilizumab. The interval between live vaccinations and initiation of tocilizumab therapy should be in accordance with current vaccination guidelines regarding immunosuppressive agents.
    Tofacitinib: (Major) Do not administer live virus vaccines to patients taking tofacitinib, as no data are available on the secondary transmission of infection by live vaccines. Also, no data are available on the response to vaccination with any vaccine during tofacitinib receipt. Before tofacitinib initiation, review the vaccination status of patients, and update immunizations in agreement with current immunization guidelines.
    Tositumomab: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Trastuzumab: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Tretinoin, ATRA: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Ustekinumab: (Severe) If possible, administer all recommended vaccines before ustekinumab initiation. Ustekinumab recipients may receive inactive vaccines, but the elicited immune response may be insufficient to prevent disease. Do not administer live vaccines to a ustekinumab recipient. Furthermore, do not administer BCG live vaccines for either 1 year before or 1 year after ustekinumab receipt, due to the infectious risk for Mycobacteria. No data are available on the response to live vaccination or on the risk of infection or infection transmission after the administration of other live vaccines to ustekinumab recipients. Cautious administration of ustekinumab to household contacts of ustekinumab recipients may be warranted due to the potential risk for shedding from the household contact and transmission to the patient. Practitioners should also refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.
    Vorinostat: (Severe) Live virus vaccines should generally not be administered to an immunosuppressed patient. Live virus vaccines may induce the illness they are intended to prevent and are generally contraindicated for use during immunosuppressive treatment. The immune response of the immunocompromised patient to vaccines may be decreased, even despite alternate vaccination schedules or more frequent booster doses. If immunization is necessary, choose an alternative to live vaccination, or, consider a delay or change in the immunization schedule. Practitioners should refer to the most recent CDC guidelines regarding vaccination of patients who are receiving drugs that adversely affect the immune system.

    PREGNANCY AND LACTATION

    Pregnancy

    The intranasal influenza vaccine (FluMist) is a pregnancy risk category B drug. No adequate and well-controlled studies have been conducted in pregnant women and the ability of the vaccine to cause fetal harm or affect reproductive capacity is unknown. The manufacturer recommends administration to pregnant women only if clearly needed. According to the Advisory Committee on Immunization Practices (ACIP), administration of live vaccines to pregnant women pose a theoretical risk to the fetus and, therefore, should be avoided. However, because pregnancy may increase the risk of serious medical complications from influenza, the ACIP recommends that all women who are pregnant or will be pregnant (in any trimester) during influenza season be routinely vaccinated with an inactivated influenza virus vaccine (see Influenza Virus Vaccine monograph).  Many experts consider the inactivated influenza virus vaccine safe during any stage of pregnancy. However, because spontaneous abortion is common in the first trimester and unnecessary drug-exposures have traditionally been avoided during this time, some experts prefer waiting until the second trimester to vaccinate.

    Data are limited regarding use of the intranasal influenza vaccine (FluMist) during breast-feeding and its' excretion in human milk is unknown. The manufacturer recommends caution when administering to nursing mothers; however according to the Advisory Committee on Immunization Practices (ACIP), live virus vaccines do not affect the safety of breast-feeding. Health care providers are advised that, although attenuated, the potential of transmitting live viruses to the infant through breast milk exists. If vaccination of a lactating woman is desirable, use of an inactivated influenza virus vaccine may be an appropriate alternative (see Influenza Virus Vaccine monograph). Consider the benefits of breast-feeding, the risk of potential infant drug exposure, and the risk of an untreated or inadequately treated condition. If a breast-feeding infant experiences an adverse effect related to a maternally administered drug, health care providers are encouraged to report the adverse effect to the FDA.

    MECHANISM OF ACTION

    The immune mechanisms that confer protection from influenza infection have not been fully elucidated. Intranasal influenza vaccine imparts immunity against the influenza virus by stimulating production of antibodies that are specific to the disease. Influenza strain-specific serum antibodies to the vaccine have been demonstrated. The intranasal route of administration also stimulates localized mucosal antibody formation and may enhance cytotoxic T-cell formation. In general, patients who receive the vaccine will be immune only to those strains of the virus from which the vaccine was prepared. In one clinical study, protection was afforded against an H3N2 strain that was not well-matched to the H3N2 strain contained in the virus, suggesting that the vaccine provided cross-protection against the variant strain.
     
    Influenza viruses are recognized by the surface antigens they carry, and two such antigens, hemagglutinin (H) and neuraminidase (N) have been identified and are used to classify the various viruses. Subtypes of these strains (H1, H2, H3, N1, N2) are associated with influenza A virus and have been recognized to cause disease in humans. Immunity to these surface antigens increases resistance to infection and decreases the severity of the disease if infection occurs. Eventually, antigenic variation can occur, and immunity to one strain may no longer impart immunity to distantly related subtypes of the virus. Influenza B viruses also exhibit antigenic variation, and new variants of both types of viruses continue to cause widespread epidemics of respiratory disease.
     
    The intranasal influenza vaccine is attenuated and thus, will not produce classic influenza-like illness. However, as the product is a live vaccine, some flu-like symptoms may occur shortly after vaccine receipt.

    PHARMACOKINETICS

    The intranasal influenza vaccine is administered topically as a fine mist to the inside of the nose. Most of the dose is deposited in the nose and nasopharynx. Post-vaccine antibody titers are generally high enough in healthy young adults and children to provide resistance against infection by influenza virus strains found in the vaccine as well as related strains. The duration of immunity imparted by the intranasal influenza vaccine is unknown; annual revaccination is needed. Influenza may be transmitted by the vaccine recipient to others. The frequency and duration of viral shedding after vaccine receipt have not been established. At least one vaccine strain was recovered from 80% of 98 FluMist recipients during the monitoring period, which was the first 21 days after vaccine receipt. The mean duration of vaccine strain detection was 7.6 +/- 3.4 days.