Health Indicator Report of Hepatitis A Infections

Hepatitis A is a contagious liver disease that results from infection with the hepatitis A virus. It can range in severity from a mild illness lasting a few weeks to a severe illness lasting several months. Hepatitis A is usually spread when a person ingests fecal matter--even in microscopic amounts--from contact with objects, food, or drinks contaminated by the feces or stool of an infected person. The best way to prevent hepatitis A is by getting vaccinated. The hepatitis A vaccine was introduced in 1995 and health professionals now routinely vaccinate all children, travelers to certain endemic countries, and persons at risk for the disease. Hepatitis A vaccination has dramatically affected rates of the disease in the United States and the number of reported cases in Utah has steadily decreased since its advent. In recent years, hepatitis A outbreaks have occurred from several different sources including foodborne transmission through ingestion of contaminated food and person-to-person transmission through close contact with an infected person, most recently, among people who use drugs, people experiencing homelessness, and men who have sex with men. Recent outbreaks have mainly affected adults. Increased vaccination efforts targeting adults in at-risk populations can help limit the size, duration, and spread of person-to-person outbreaks. Surveillance data are used to detect outbreaks, determine the effectiveness of hepatitis A vaccination, monitor disease incidence in all age groups, determine the epidemiologic characteristics of infected persons including the source of infection, and assess and reduce missed opportunities for vaccination. While the average number of annual hepatitis A virus (HAV) infections reported to CDC in recent years has declined substantially compared to 2000, fluctuations have occurred in the last 20 years because large outbreaks occurred.