General Information
Prior to administration, inform the parent, guardian, or responsible adult of the benefits and risks of the vaccine, and provide the Vaccine Information Statement, accessible at the Centers for Disease Control and Prevention (CDC) website. These actions are required by the National Childhood Vaccine Injury Act of 1986. If a dose of influenza virus vaccine, inactivated has been previously given, question the parent or guardian about previous adverse reactions that may preclude further administration. Report all adverse reactions to the Vaccine Adverse Event Reporting System (VAERS), as well as the manufacturer. The toll-free number for VAERS is 1—800—822—7967. Educate the responsible adult(s) to promptly report any adverse reaction after vaccine administration to a health care provider.
Intravenous administration, subcutaneous administration
Influenza virus vaccine should not be given via intravenous administration or subcutaneous administration, it is for intramuscular (IM) administration only, with the exception of the intradermal Fluzone products. All other formulations should not be given by intradermal administration. Incorrect administration may result in inadequate immunity.
Fever
The decision to administer or to delay vaccination with the influenza virus vaccine because of current or recent febrile illness depends on the severity of symptoms and on the etiology of the disease. Consider delaying vaccinations during the course of a moderate or severe acute illness with or without fever and administer after the acute phase of illness has resolved. All vaccines can be administered to persons with mild illnesses. Persons with moderate or severe febrile illness should be vaccinated as soon as they have recovered from the acute phase of the illness.[65107]
Egg hypersensitivity
All formulations of the inactivated influenza vaccine (IIV), with the exception of Flucelvax and Flublok, are contraindicated by the manufacturer for use in persons with a known history of a severe allergic reaction (e.g., anaphylaxis) to the vaccine or any of its components, persons who have had a life-threatening reaction to any previous influenza vaccination, or persons with egg hypersensitivity.[41448] [51849] [51850] [52652] [54943] [55717] [58656] Due to differences in manufacturing processes, Flucelvax and Flublok do not use eggs to propagate the virus; thus, they are only contraindicated in persons with a known history of a severe allergic reaction (e.g., anaphylaxis) to the vaccine or any of its components.[52415] [52915] Flucelvax, however, cannot be considered 100% egg-free because the initial seed virus is created using reference virus stains from the World Health Organization, which have been passaged in eggs. The Advisory Committee on Immunization Practices (ACIP) recommends administering any licensed influenza vaccine (i.e., any IIV, quadrivalent recombinant influenza vaccine (RIV4), or quadrivalent live-attenuated influenza vaccine (LAIV4)) to patients with egg allergy of any severity. Patients who have had symptoms other than urticaria after egg exposure (i.e., angioedema, respiratory distress, lightheadedness, or recurrent emesis) or required emergency medical intervention, may also receive any licensed, age-appropriate influenza vaccine; however, it is recommended that the vaccine only be administered in an inpatient or outpatient medical setting by a health care provider experienced in the recognition and management of severe allergic conditions. Severe allergic reactions to vaccines can occur in patients without a history of previous allergic reaction. A previous severe allergic reaction to influenza vaccine is a contraindication to receiving future influenza vaccines. Although no specific observation time is recommended for egg-allergic patients, ACIP recommends patients be observed for syncope for 15 minutes after vaccination. [63436] The American Academy of Pediatrics (AAP), the American Academy of Allergy, Asthma, and Immunology (AAAAI), and the American College of Allergy, Asthma, and Immunology (ACAAI) do not recommend any special precautions for egg-allergic recipients, regardless of severity. The AAAAI and ACAAI consider any special precautions (i.e., special observation periods or administration in a specialized medical setting) unnecessary due to the extremely rare risk of anaphylactic reactions after vaccination. They recommend that providers and screening questionnaires not ask about the egg allergy status of the influenza virus vaccine recipient.[62809] [63520] As with any biologic product, the prescriber or health care professional should have procedures in place to manage allergic reactions. The health care professional should have immediate availability of epinephrine (1 mg/mL) injection and other agents used in the treatment of severe anaphylaxis in the event of a serious allergic reaction to the influenza virus vaccine.[41448] [51849] [51850] [52652] [54943] [55717] [60361] [60831]
Guillain-Barre syndrome
Carefully consider the potential benefits and risks of the inactivated influenza vaccine (IIV) for patients who have developed Guillain-Barre syndrome (GBS) within 6 weeks of a previous influenza vaccination. Influenza immunization is generally not recommended in patients who have developed GBS within 6 weeks of a previous influenza vaccination. However, for most persons with a history of GBS who are at high risk for severe complications from influenza, many experts believe the benefits of the influenza virus vaccine justify yearly vaccination.
Geriatric
Geriatric persons may develop lower postvaccination antibody titers than healthy young adults and, thus, may remain susceptible to influenza-related upper respiratory tract infection (see Pharmacokinetics). However, even if such persons develop influenza illness despite vaccination, the vaccine can be effective in preventing lower respiratory tract infection or other secondary complications, thereby reducing the risk for hospitalization and death. In a retrospective study of data from 1990—2000, influenza vaccination was associated with significant reductions in the risk of hospitalization for pneumonia or influenza and in the risk of death among community-dwelling patients at least 65 years of age as compared with unvaccinated patients. Specifically, vaccination was associated with a 27% reduction in the risk of hospitalization for pneumonia or influenza and a 48% reduction in the risk of death. Statistically significant reductions in the risk of both hospitalization and death were also found by sensitivity analyses, which modeled the effect of a hypothetical unmeasured confounder that would have caused overestimation of vaccine effectiveness. In elderly nursing home residents, administration of the flu vaccine annually prior to October should generally be avoided because antibody concentrations can decrease within a few months of immunization.
Pregnancy
No adequate and well-controlled studies have been conducted in pregnant women, and the ability of the vaccine to cause fetal harm or to affect reproductive capacity is unknown. During animal studies, no evidence of impaired fertility or fetal harm was noted with Afluria, Agriflu, Fluarix, Flublok, Flucelvax, FluLaval, Fluvirin, or Fluzone Quadrivalent or Intradermal. Pregnancy may increase the risk of serious medical complications from influenza. Therefore, the Advisory Committee on Immunization Practices (ACIP) recommends that all women who are or will be pregnant (in any trimester) during the influenza season be routinely vaccinated with an inactivated influenza vaccine (vs. live-attenuated influenza vaccine).[63436] Although more data are needed, studies of more than 2,000 pregnant women have demonstrated no adverse fetal effects associated with influenza virus vaccine. Many experts consider influenza vaccination 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 of pregnancy to vaccinate. In addition to benefits to the mother, influenza vaccine administration during pregnancy appears to help protect newborns and infants. Fewer cases of laboratory-confirmed influenza occurred during the first 6 months of life among infants of the 159 mothers who received the inactivated influenza vaccine (6 cases) as compared with infants of 157 mothers who received the pneumococcal polysaccharide vaccine (16 cases). The clinical judgment of the physician is paramount in the determination of whether to vaccinate a pregnant woman. Some manufacturers have established pregnancy registries to monitor pregnancy outcomes and newborn health after vaccination. Patients who receive these vaccines during pregnancy are encouraged to enroll in these registries. For GlaxoSmithKline (GSK) influenza vaccines (e.g., FluLaval and Fluarix), patients are encouraged to contact GSK by telephone at 888-452-9622. For Sanofi Pasteur influenza vaccines (e.g., Fluzone and Flublok), patients are encouraged to contact Sanofi Pasteur at 800-822-2463. For Seqirus influenza vaccines (e.g., Afluria and Afluria Quadrivalent), patients are encouraged to contact Seqirus at 855-358-8966 or us.medicalinformation@seqirus.com.[28647] [30823] [34402] [41448] [41684] [41685] [41686] [47301] [52415] [52652] [52915] [54943] [55717] [65107]
Breast-feeding
Data are limited regarding use of the influenza virus vaccine during breast-feeding, and its' excretion in human breast milk is unknown. The Advisory Committee on Immunization Practices (ACIP) and the American Academy of Pediatrics (AAP) state inactivated virus vaccines pose no risk for mothers or their infants. Additionally, breast-feeding does not adversely affect immunization; limited data suggest breast-feeding may enhance the immune response to certain vaccine antigens. 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.[41686] [30823] [41685] [41448] [41684] [47301] [52652] [63520] [65107]
Anticoagulant therapy, coagulopathy, hemophilia, thrombocytopenia, vitamin K deficiency
Patients with thrombocytopenia or a coagulopathy (e.g., hemophilia), vitamin K deficiency, or who are on anticoagulant therapy should be monitored closely when given influenza virus vaccine because bleeding can occur at the IM injection site.
Acquired immunodeficiency syndrome (AIDS), human immunodeficiency virus (HIV) infection
Although patients with human immunodeficiency virus (HIV) infection or acquired immunodeficiency syndrome (AIDS) could have a diminished response, inactivated influenza vaccine (IIV) should be offered to these patients.[34361] [34362] [60092] The CDC recommends immunization of HIV-infected individuals with the IIV, as this measure is safe and may confer protection against influenza.[60092] [63436] One randomized, placebo-controlled trial noted that the administration of IIV 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).[26272]
Syncope
Injectable vaccines, including influenza virus vaccine, have been associated with episodes of syncope and fainting. These events may be accompanied by transient tonic-clonic limb movements, visual disturbances, and paresthesias. Prior to administration, ensure procedures are in place to prevent falls and restore cerebral perfusion. Monitor vaccine recipients after administration of the dose. If syncope occurs, place the patient in a supine or Trendelenburg position to restore cerebral perfusion.
Agammaglobulinemia, hypogammaglobulinemia, immunosuppression, severe combined immunodeficiency (SCID)
Patients with significant immunosuppression may not have an adequate antibody response to the inactivated influenza vaccine (IIV).[41448] Immunosuppressed persons may include patients with severe combined immunodeficiency (SCID), hypogammaglobulinemia, agammaglobulinemia, or an immune system compromised by drug therapy (i.e., corticosteroid therapy with greater than physiologic doses). Short-term (less than 2 weeks) corticosteroid therapy or intra-articular, bursal, or tendon injections with corticosteroids should not be immunosuppressive. Patients vaccinated with IIV within 2 weeks before starting immunosuppressive therapy or while receiving immunosuppressive therapy should be considered unvaccinated and should be revaccinated at least 3 months after therapy is discontinued if immune competence has been restored. IIV can be administered to patients with major antibody deficiencies and some residual antibody production.[65107]
Neoplastic disease, organ transplant, radiation therapy
Patients with altered immune states due to generalized neoplastic disease or an immune system compromised by radiation therapy or drug therapy (e.g., chemotherapy or corticosteroid therapy with greater than physiologic doses) may not have an adequate antibody response to the inactivated influenza vaccine (IIV).[41448] Patients with hematological malignancies or solid tumor malignancies, except those receiving anti-B-cell antibodies or intensive chemotherapy (i.e., induction or consolidation chemotherapy for acute leukemia), should receive IIV annually. Patients vaccinated with IIV within 2 weeks before starting immunosuppressive therapy or while receiving immunosuppressive therapy should be considered unvaccinated and should be revaccinated at least 3 months after therapy is discontinued if immune competence has been restored.[60092] [65107] IIV should not be administered to solid organ transplant (SOT) recipients during intensified immunosuppression, including the first 2 months post-transplant, because of the likelihood of inadequate response. However, IIV can be administered beginning 1 month after transplant during a community influenza outbreak and should be administered 2 to 6 months after SOT. Concerns have been raised that vaccination may trigger rejection; however, clinical evidence indicates that vaccines are not important triggers of rejection episodes and should not be withheld for that reason.[60092]