Virus - Hepatitis A

female in lab protective gear working with Hepatitis A virus
(Image courtesy of CDC)

Hepatitis A

Compiled By: Julie A. Albrecht, Ph.D., Associate Professor

The Organism: The Hepatitis A virus is an ultramicroscopic organism that must have a living host to multiply. Food is used to transmit the viruses from person to person. The virus, when transferred to food, may survive for several days, even at refrigeration temperatures.

  PDF Fact Sheet

Sources of the organism:

  • Intestinal tracts of infected humans
  • Contaminated water

Associated foods:

  • Seafood
  • Any food handled by an infected food handler

Organism Characteristics:

  • Virus; needs a live host to reproduce

The Disease: Persons with Hepatitis A foodborne illness may shed the virus in their feces long before disease symptoms appear. Persons infected with Hepatitis A virus should not handle food or work in a food establishment until they have received the proper medical treatment and are no longer shedding the virus. Hepatitis A vaccine is available.

Symptoms include:

  • Lethargy
  • Loss of appetite
  • Nausea
  • Vomiting
  • Fever
  • Jaundice

Onset time:

  • 10-50 days
  • Infective Dose:
  • Unknown but presumably 10-100 virus particles need to be consumed for symptoms of the illness to develop.

Duration of symptoms:

  • 2 weeks - 3 months


  • Thoroughly cook seafood including oysters.
  • Use proper hand washing techniques and practice good personal hygiene procedures.