For health professionals: Hepatitis A
Find detailed information on hepatitis A for health professionals.
On this page
- What health professionals need to know about hepatitis A
- Clinical manifestations
- Diagnosis
- Treatment
- Prevention and control
- Hepatitis A surveillance in Canada
- For more information
What health professionals need to know about hepatitis A
The hepatitis A virus is a member of the Picornaviridae family and Hepatovirus genus. It is an icosahedral, non-enveloped, positive-sense ribonucleic acid virus.
There have been 7 hepatitis A genotypes identified (I-VII), 4 of which are of human origin (I, II, III and VII).
Clinical manifestations
Hepatitis A only causes acute hepatitis and is not associated with chronic liver disease. However, individuals with pre-existing liver disease may suffer severe complications.
Most individuals infected with hepatitis A develop non-specific constitutional signs and symptoms followed by gastrointestinal symptoms.
The disease course typically lasts less than 2 months.
In rare cases, hepatitis A can cause severe cases of fulminant hepatitis with fatal outcomes in otherwise healthy adults.
Diagnosis
A number of techniques have been employed to detect hepatitis A virus, including:
- immunoblotting
- radioimmunoassay
- dot-blot gold filtration
- real-time polymerase chain reaction (RT-PCR)
- enzyme-linked immunosorbent assays (ELISA)
Treatment
Vaccination can help prevent hepatitis A in those exposed to the virus if given within 2 weeks of exposure.
No specific treatment for hepatitis A virus infection has been shown to be effective.
However, the following treatments are recommended:
- bed rest
- balanced nutrition
- avoidance of alcohol or other hepatotoxins
Prevention and control
Hepatitis A is one of the most common vaccine-preventable illnesses in travellers. The vaccine is recommended for persons 6 months of age and older who are at increased risk of:
- infection
- severe hepatitis A
All persons who wish to decrease their risk of becoming infected with the hepatitis A virus should be vaccinated. Hepatitis A vaccines have demonstrated at least 90% to 97% effectiveness in preventing clinical illness.
In particular, the following groups are recommended to be vaccinated for hepatitis A prevention:
- travellers to hepatitis A-endemic areas
- household or close contacts of children adopted from hepatitis A-endemic countries
- individuals living in communities at risk of hepatitis A outbreaks or in which hepatitis A is endemic
- military personnel and humanitarian relief workers likely to be posted to areas with high rates of hepatitis A
- persons with lifestyle risks for infection, including:
- men who have sex with men
- those who engage in disordered use of injectable and non-injectable substances
- zoo keepers, veterinarians and researchers who handle non-human primates
- people receiving repeated replacement of plasma-derived replacement clotting factors
- workers involved in research on the hepatitis A virus or the production of the hepatitis A vaccine who may be exposed to the virus
- persons who have chronic liver disease from any cause, including persons infected with hepatitis C and chronic hepatitis B carriers
- these persons are at risk of more severe disease if infection occurs
Vaccination should also be considered for persons new to Canada who are from countries where hepatitis A is endemic. Individuals born in countries where hepatitis A is endemic are more likely to be immune. Therefore, testing these individuals for immunity prior to administering the vaccine should be considered.
Consult the Hepatitis A vaccines: Canadian Immunization Guide, for additional information on post-exposure immunization.
Hepatitis A surveillance in Canada
You must report hepatitis A cases to your local medical officer of health.
Health professionals in Canada play a critical role in identifying and reporting cases of hepatitis A. Refer to the surveillance section for more information on surveillance in Canada.
Consult the national case definition for additional information.