Typhoid

Hepatitis A virus (HAV) is one of the most common causes of viral hepatitis. About 1.4 million HAV infections every year worldwide is reported by WHO. It is usually transmitted by the fecal-oral route, either through person-to-person contact or consumption of contaminated food or water. Symptoms of HAV infection include fever, weakness, nausea, diarrhea, and jaundice. Although there is no specific treatment for HAV infection, therapy aims to maintain patient comfort and provide adequate nutritional balance. In most cases HAV is self-limiting, however, in 0.5% of patients it may lead to fulminant hepatitis and death. HAV infection can be prevented by vaccination and by maintaining proper sanitation methods. Serological tests are used for the detection and differentiation of HAV from other viral hepatitis infections. Acute HAV infection is routinely diagnosed by the presence of HAV IgM antibodies which rapidly increase over a period of 4-6 weeks following infection. Anti-HAV IgM titers will decline to undetectable levels within 3 to 6 months in most patients. Detection of anti-HAV IgG in the absence of anti-HAV IgM is used to identify previous exposure to the disease or vaccination.