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Hepatitis A Vaccine

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Hepatitis A Vaccine, Havrix, Vaqta

  • See Also
  1. Hepatitis A Virus
  2. Combined Hepatitis A and Hepatitis B Vaccine (Twinrix)
  3. Hepatitis A Immunoglobulin
  • Indications
  1. All children as Primary Series at age 1 year
    1. Children are reservoir for Hepatitis A (May erradicate Hepatitis A from population)
  2. Travelers to endemic Hepatitis A areas
    1. All regions outside United States, Western Europe, New Zealand, Australia, Japan and Canada
  3. Close contact with international adoptee
  4. Food handlers
  5. Workers with primates
  6. Day care workers or children
  7. Occupational exposure or other exposure to those at high risk for Hepatitis A
  8. Illicit Drug use
  9. Homosexual male
  10. Homelessness
  11. High risk of Hepatitis A complication
    1. Chronic Liver Disease
    2. Age over 40 years
    3. HIV Infection
  12. Patients living in endemic regions of United States or in regions of outbreaks
    1. https://www.cdc.gov/hepatitis/outbreaks/hepatitisaoutbreaks.htm
  13. Cases in which cohort is no longer at high risk to require Hepatitis A Vaccine
    1. Clotting Factor disorder (transfusion risk)
  • Preparation
  1. See Twinrix (combination with Hepatitis B Vaccine)
  2. Hepatitis A Vaccine (Havrix, Vaqta)
  • Dosing
  • Havrix or Vaqta
  1. Start Vaccine at least 4 weeks before departure
    1. Give Hepatitis A Immunoglobulin if less than 4 weeks before departure
      1. See Hepatitis A Immunoglobulin for other indications
  2. Infants (>12 month)
    1. May also administer to ages 6-12 months for international travel to endemic regions
    2. Dose 1: 0.5 ml IM at month 0, after age 12 months (or after 6 months old, before travel to endemic region)
    3. Dose 2: 0.5 ml IM at month 6-12, at least 6 months after first dose
  3. Children (ages 1 to 18 years)
    1. Dose 1: 0.5 ml IM at month 0 (U.S. Primary Series administers at age 12 months)
    2. Dose 2: 0.5 ml IM at month 6-12 (U.S. Primary Series administers at age 18-24 months)
  4. Adult (ages 19 years and older)
    1. Dose 1: 1 ml IM at month 0
    2. Dose 2: 1 ml IM at month 6-12
  • Dosing
  • Indications for administering Immoglobulin in impending out of country travel
  1. Age under 1 year old (Immunoglobulin Alone)
  2. Serious comorbidity (Vaccine and Immunoglobulin)
  3. Age over 40 years old (Vaccine and immoglobulin)
  • Precautions
  1. Safe in HIV
    1. See Immunization in HIV
  2. Safe in Pregnancy
    1. See Immunization in Pregnancy
  3. Not indicated for under age 1 years
    1. Use Hepatitis A Immunoglobulin for exposure
  • Adverse Effects
  1. Purpura (ages 7 to 17 years old)
  • Efficacy
  1. Protective antibodies after dose 1
    1. Two weeks: 37% of patients
    2. Four weeks: >90% of patients
    3. Twenty-six weeks: 100% of patients
  2. Long-term protection occurs with dose 2
    1. Protection lasts at least 20 years after series
  3. Hepatitis A Incidence reduced 95% since Vaccine introduction
  • Resources
  1. CDC Immunization Schedules (last accessed 10/28/2020)
    1. https://www.cdc.gov/vaccines/hcp/imz-schedules/index.html
  • References
  1. Ackerman (2015) Am Fam Physician 92(6): 460-8 [PubMed]
  2. (2001) Med Lett Drugs Ther 43(1110):67-8 [PubMed]
  3. Craig (2004) N Engl J Med 350:476-81 [PubMed]