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. The disease is closely associated with unsafe water, inadequate sanitation and poor personal hygiene.
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). Adults have signs and symptoms of illness more often than children and the severity of disease and mortality increases in older age groups.
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. 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: The annual incidence of 2.2 to 2.5 per 100 000 during 2002-2004 represents a 95% or greater reduction for each year with respect to the mean incidence during 1993-1998 (P<.001). For children aged 1 through 4 years, a 98.2% reduction in disease was observed in 2002-2004, compared with the prevaccination period (P<.001).