Chapter 3, Hepatitis A: 3 --1 Chapter 3: Hepatitis A

Abstract

ronic liver disease. II. Background In the United States, large nationwide epidemics have occurred approximately every 10 years, with the last increase in cases in 1995. 2 However, even between these epidemics, disease rates are relatively high and many communities experience periodic epidemics. Until recently, hepatitis A was one of the most frequently reported vaccine-preventable diseases in the U.S. with 20,000--30,000 cases reported to the NNDSS. In 2000, 13,397 hepatitis A cases were reported for a rate of 4.87 cases per 100,000 population. This is the lowest rate of disease ever reported in the U.S. and represents, after correcting for underreporting and asymptomatic infections, an estimated 57,000 cases and 143,000 infections, respectively. This remarkable decline in cases could be the result of vaccination of children, begun in selected areas in 1996. Based on testing from the Third National Health and Nutrition Examination Survey (NHANES III) survey conducted during 1988--