Hepatitis A virus

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Revision as of 08:53, 20 November 2019 by Aidan (talk | contribs) (added incubation period)

Background

Microbiology

  • Non-enveloped RNA virus within the Picornavirus family
  • Three genotypes, I through III
  • Difficult to kill: needs higher temperatures and lower pH than other viruses, or bleach- or ammonium-based cleaners

Epidemiology

  • Fecal-oral transmission with person-to-person spread (including sex)
  • Can be transmitted by contaminated food and water, as well
  • Most often linked to travel or to household contacts

Clinical Presentation

  • Incubation period is from 15 to 50 days, with an average of 28 days

Diagnosis

Serology

IgM IgG Interpretation
No recent infection (unless in the incubation period). No prior infection or vaccination.
+ No infection. Prior infection or vaccination.
? + Cannot rule out active infection. Prior infection or vaccination.
+ +/– Acute or recent infection. IgM positive from 2 weeks until 3-12 months. IgG positive from 8-12 weeks and remains positive for lifetime.