The incubation period (time between exposure to the virus and the development of symptoms) varies between 15 and 50 days, with an average of 30 days. Hepatitis A virus is excreted for up to two weeks before the onset of symptoms. Therefore, people with hepatitis A should be considered infectious for a week after the onset of jaundice.
Hepatitis A is diagnosed by a blood test. The detection of IgM hepatitis A antibodies (anti-HAV IgM) confirms recent infection. These antibodies are present for three to six months after infection. The detection of IgG hepatitis A antibodies (anti-HAV IgG) indicates past infection and immunity against hepatitis A infection.
Liver function test (LFTs) abnormalities, specifically elevated serum bilirubin and serum aminotransferase (ALT and AST) values, may also indicate acute liver infection.
Testing for hepatitis D can be done through a simple blood test by your GP or liver specialist. Usually, doctors look for hepatitis D in people who have severe or rapidly progressive hepatitis B. In these cases, doctors will test your blood for various markers of acute or chronic HDV infection. Based on the pattern of the disease and the results of the blood tests for HBV and HDV, doctors can estimate whether the infection is acute, chronic or a superinfection.
The time between infection with hepatitis E and development of symptoms ranges from 15 to 60 days, with an average of 40 days. Diagnosis of hepatitis E is performed by a blood test that detects either the antibodies or the virus itself. The blood tests needed to diagnose hepatitis E are not widely available in Australia.