hepatic and biliary disorders
Hepatitis A
Introduction
Hepatitis A is caused by an enterically transmitted RNA virus that, in older children and adults, causes typical symptoms of viral hepatitis, including anorexia, malaise, and jaundice. Young children may be asymptomatic. Fulminant hepatitis and death are rare in countries that have adequate and effective water treatment and sanitation facilities. Chronic hepatitis does not occur. Diagnosis is by antibody testing. Treatment is supportive. Vaccination and previous infection are protective. (See also Causes of Hepatitis and Hepatitis A virus (HAV) is a single-stranded RNA picornavirus. It is the most common cause of acute viral hepatitis and is particularly common among children and young adults. 75% of adults have been exposed to HAV. In the US in 2018, 12,474 cases were reported, and an estimated 24,900 cases occurred (many cases are not recognized or not reported [ General references ]). Worldwide, an estimated 1.4 million cases of hepatitis A occur each year ( HAV spreads primarily by fecal-oral contact and thus may occur in areas of poor hygiene. Waterborne and food-borne epidemics occur, especially in countries that do not have adequate and effective water treatment and sanitation facilities. Eating contaminated raw shellfish is sometimes responsible. Sporadic cases are also common, usually as a result of person-to-person contact. Fecal shedding of the virus occurs before symptoms develop and usually ceases a few days after symptoms begin; thus, infectivity often has already ceased when hepatitis becomes clinically evident. HAV has no known chronic carrier state and does not cause Overview of Chronic Hepatitis or 