Hepatitis A: Hepatitis A is a liver disease caused by the hepatitis A virus. The virus is primarily spread when an uninfected (and unvaccinated) person ingests food or water that is contaminated with the faeces of an infected person. Symptoms: The incubation period of hepatitis A is usually 14–28 days. Symptoms of hepatitis A range from mild to severe, and can include fever, malaise, loss of appetite, diarrhoea, nausea, abdominal discomfort, and dark-coloured urine and jaundice (a yellowing of the skin and whites of the eyes).
Causes : Hepatitis A usually get it when you eat or drink something that's got the virus in it. It's the least risky type because it almost always gets better on its own. It doesn't lead to long-term inflammation of your liver. Even so, about 20% of people who get hepatitis A get sick enough that they need to go to the hospital. There's a vaccine that can prevent it. Diagnosis: Hepatitis A is not clinically distinguishable from other types of acute viral hepatitis. Specific diagnosis is made by the detection of HAV-specific IgM and IgG antibodies in the blood. Additional tests include reverse transcriptase polymerase chain reaction (RT-PCR) to detect the hepatitis A virus RNA, but may require specialised laboratory facilities.
Treatment: There is no specific treatment for hepatitis A. Recovery from symptoms following infection may be slow and may take several weeks or months. Therapy is aimed at maintaining comfort and adequate nutritional balance, including replacement of fluids that are lost from vomiting and diarrhoea.
statistics: Hepatitis A has been a relevant public health problem in China. More than 300 000 cases of clinical hepatitis A were reported during a shellfish-associated outbreak in Shanghai in 1988; however, in the following two decades, the annual national incidence rate of hepatitis A dropped dramatically. In urban China in the early 1990s, although up to one-half of 10 year olds had antibodies to hepatitis A, the seroprevalence in most cities did not reach 100%, even for those aged 60 and above, leaving susceptible population groups and creating the possibility of outbreaks.