Transmission and prevention

Hepatitis A is most often transmitted from person-to-person via the faecal-oral route. It may be spread through close household or personal contact and through certain sexual practises, notably oral-anal sex (anilingus or rimming). The hepatitis A virus may also spread through contaminated water or food, most often undercooked shellfish or raw fruits or vegetables.1 2

Several hepatitis A outbreaks have been reported amongst gay and bisexual men.3 4 For example, a cluster of 69 cases possibly attributable to sexual transmission between men was reported in Norway in 2004.5 Likewise, in the autumn of 2004 the United Kingdom's Health Protection Agency identified a hepatitis A outbreak amongst nine gay men in London, most of whom frequented a particular pub with a darkroom where sexual activity took place.6 Other recent outbreaks have been reported in Denmark, France, Germany, the Netherlands, and Sweden.7 5 Whilst some studies have associated hepatitis A virus transmission with a larger number of sex partners and specific sexual practises, other research has not found a link with homosexual activity.8 9 10 11

Although hepatitis A virus is not considered primarily a blood-borne infection like hepatitis B and C viruses, cases have been attributed to blood product transfusion.12 Injecting and non-injecting drug users also have higher rates of hepatitis A infection.11 Mother-to-child transmission during pregnancy and delivery or through breastfeeding is rare. In about half of all cases, the transmission route is unknown.

Hepatitis A can be prevented by practising good hygiene, including hand-washing after using the toilet or changing nappies, and before preparing or eating food. Avoid drinking untreated water when travelling in areas where hepatitis A is common. Also, avoid sharing items such as razors, toothbrushes or needles for injecting drugs. Safer sex practices, in particular use of barrier devices for oral-anal sex, can help reduce the risk of transmission.

References

  1. Conaty S et al. Hepatitis A in New South Wales, Australia from consumption of oysters: the first reported outbreak. Epidemiol Infect 124: 121-130, 2000
  2. Wheeler C et al. An outbreak of hepatitis A associated with green onions. N Engl J Med 353: 890-897, 2005
  3. Centers for Disease Control (CDC) Hepatitis A among homosexual men - United States, Canada, and Australia. MMWR Morb Mortal Wkly Rep 41: 155, 161-154, 1992
  4. Henning KJ et al. A community-wide outbreak of hepatitis A: risk factors for infection among homosexual and bisexual men. Am J Med 995: 132-136, 1999
  5. Blystad H et al. Hepatitis A outbreak in men who have sex with men, Oslo and Bergen in Norway. Eurosurveillance Weekly 8, 2004
  6. Health Protection Agency Outbreak of hepatitis A in men who have sex with men in south east London. Commun Dis Rep CDR Weekly 14, 2004
  7. Mazick A et al. Hepatitis A outbreak among MSM linked to casual sex and gay saunas in Copenhagen, Denmark. Euro Surveill 10: 111-114, 2005
  8. Coutinho RA et al. Prevalence and incidence of hepatitis A among male homosexuals. Br Med J 287: 1743-1745, 1983
  9. Katz MH et al. Seroprevalence of and risk factors for hepatitis A infection among young homosexual and bisexual men. J Infect Dis 175: 1225-1229, 1997
  10. Ross J et al. Seroprevalence of hepatitis A immunity in male genitourinary medicine clinic attenders: a case control study of heterosexual and homosexual men. Sex Transm Infect 78: 174-179, 2002
  11. Villano S et al. Hepatitis A among homosexual men and injection drug users: more evidence for vaccination. Clin Infect Dis 25: 726-728, 1997
  12. Chudy M et al. A new cluster of hepatitis A infection in hemophiliacs traced to a contaminated plasma pool. J Med Virol 57: 91-99, 1999
This content was checked for accuracy at the time it was written. It may have been superseded by more recent developments. NAM recommends checking whether this is the most current information when making decisions that may affect your health.