Hepatitis A Vaccine

Aka: Hepatitis A Vaccine, HAVRIX, VAQTA

1. 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 except western europe, New Zealand, Australia, Japan and Canada
   3. Close contact with international adoptee
   4. Children living in endemic states of United States
      1. Arizona (highest Prevalence in United States)
      2. Alaska
      3. Oregon
      4. New Mexico
      5. Utah
      6. Washington
      7. Oklahoma
      8. South Dakota
      9. Idaho
      10. Nevada
      11. California
   5. Food handlers
   6. Workers with primates
   7. Day care workers or children
   8. Illicit Drug use
   9. Homosexual male
   10. Chronic Liver Disease
   11. Clotting Factor disorder
2. Preparation
   1. See also Twinrix
   2. Hepatitis A Vaccine (HAVRIX, Vaqta)
3. Dosing
   1. Start Vaccine at least 4 weeks before departure
      1. Administer Hepatitis A Immunoglobulin if less
   2. Children (ages 1 to 18 years)
      1. Dose 1: 0.5 ml IM at month 0
      2. Dose 2: 0.5 ml IM at month 6-12
   3. 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
4. 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)
5. 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
6. 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
7. References
   1. (2001) Med Lett Drugs Ther 43(1110):67-8
   2. Craig (2004) N Engl J Med 350:476-81