Hepatitis A history and symptoms

History and Symptoms
Hepatitis A virus (HAV) can produce either asymptomatic or symptomatic infection in humans after an average incubation period of 28 days (range: 15--50 days). Peak infectivity occurs during the 2-week period before onset of jaundice or elevation of liver enzymes, when concentration of virus in stool is highest. Illness caused by HAV typically has an abrupt onset that can include fever, malaise, anorexia, nausea, abdominal discomfort, dark urine, and jaundice. The likelihood of having symptoms with HAV infection increases with age. Fewer than 10% of infections among children aged 0-4 years result in jaundice; this percentage increases to 30%-40% among children aged 5-9 years, 60%-80% among youths aged 10-17 years, and 80%-90% among adults aged ≥18 years. When signs and symptoms occur, typically they last <2 months, although 10%-15% of symptomatic persons have prolonged or relapsing disease lasting up to 6 months. The case-fatality rate for HAV infection increases with age: 1.8% for persons adults aged >50 years compared with 0.6% for persons aged <50 years. The case-fatality rate is also increased among persons with chronic liver disease, who are at increased risk for acute liver failure.

HAV has an incubation period of about 28 days (anywhere from 15 to 50 is usual). Some patients, often young children, have no symptoms. 70% of children younger than 6 who have HAV have no symptoms. Old patients are usually symptomatic. The symptoms of HAV are: Symptoms typically last less than 2 months, but 10%-15% of patients still have symptoms or have relapses up to 6 months after the onset of symptoms. Unlike other instances of Hepatitis (such as Hepatitis C), HAV is always acute.
 * Fever
 * Fatigue
 * Loss of appetite
 * Nausea
 * Vomiting
 * Abdominal pain
 * Dark urine
 * Clay-colored bowel movements
 * Joint pain
 * Jaundice. Younger children (<6 yrs) typically do not get Jaundiced, while older patients often (>70%) do.