INFLUENZA VACCINE


See also "Influenza"

Indications per CDC 2005 (MMWR Recomm Rep 205;54(RR08):1-40):

  • Age > 50y
  • Children 6-23mos old (expanded to 6mos-5y in 2006--FP News 3/15/06)
  • Women who will be in 2nd or 3rd trimester during influenza season
  • Residents of chronic care facilities
  • Those who can transmit influenza to those at high risk, e.g. elderly, pts < 2yo, transplant recipients, & people with AIDS, including health care workers & other care providers
  • Adults & children with the following chronic conditions:
  • Chronic pulmonary disease
  • Chronic cardiovascular diseases
  • Neurologic conditions which compromise respiratory function or ability to handle respiratory secretions
  • Chronic illness with recent regular medical followup or hospitalization (e.g. diabetes, renal dysfunction, hemoglobinopathies, immunosuppression)
  • Patients with HIV
  • Pts aged 6mos-18y who are on long-term ASA & therefore at risk of getting Reye's after influenza
  • Timing: mid-October to mid-November

    Dosage:

  • 0-5 mos of age: not given (prob. not needed or effective)
  • 6-35mos: 0.25 ml (if 1st time getting it, 2 doses at least 4 wks apart)
  • 3-8 years: 0.5 ml (if 1st time getting it, 2 doses at least 4 wks apart)
  • 9 years & older: 0.5 ml
  • In young low-risk adults:

    In kids:

    Association with Guillain-Barre syndrome:

    Intranasal Influenza Vaccine ("Live Attenuated Influenza Vaccine," "FluMist")

    1. A live-attenuated vaccine
    2. Apparently effective c/w placebo at preventing URIs (JAMA 282:137, 1999--JW)
    3. Ass'd with RR 3.5 for asthma exacerbation within 6wks after vaccination in children < 5yo in one unpublished placebo-controlled trial (Med. Lett. 45:65, 2003)
    4. Comparisons with inactivated influenza vaccine
      1. In a study in 8,352 children 6-59mo randomized to inactivated vs. intranasal influenza vaccine, the intranasal group had sig. lower incidence of influenza-like illness (3.9% vs. 8.6%) but any-cause hospitalization in 6mos after vaccination among children < 1yo was sig. more common with intranasal vaccine (6.1% vs. 2.6%); no such association in older children (NEJM 356:685, 2007--JW)
    5. Dosing: One dose unless 5-8yo and no prior influenza immunization (in which case give 2nd dose after 6-10wks)
    6. Contraindications as of 9/2005:
      1. Age < 5yo or > 50yo
      2. Pregnancy
      3. Chronic cardiovascular, pulmonary, metabolic (including DM), or renal disease, or hemoglobinopathies
      4. Hypersensitivity to egg proteins
      5. Immunocompromise including HIV infection
      6. History of Guillain-Barre syndrome
      7. Respiratory illness within 72h
      8. Recent (< 48h previous) anti-influenza therapy
      9. Children or adolscents on chronic ASA (because of association between Reye's syndrome and coincident use of ASA and wild-type influenza infection)

    CDC recommendations for H1N1 influenza vaccinations 8/2009 (MMRW 58:1, 8/28/09)-Priority to the following target groups:

    Vaccination for pts > 65yo recommended only after demand is met in all younger groups since older pts have lower risk for infection