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AN EPIDEMIOLOGY PUBLICATION OF THE PUBLIC HEALTH DIVISION OREGON DEPARTMENT OF HUMAN SERVICES

ONLY SEVEN YEARS after the recommendation for universal childhood vaccination against hepatitis A, the once volatile disease has nearly vanished in Oregon: its incidence fell from 44 cases per 100,000 persons in 1996 to 1.8 during 2002–2004. In this issue of the CD Summary, we examine the relationship between universal vaccination and the precipitous decline in hepatitis A, and explore its changing epidemiology. UNIVERSAL HEPATITIS A VACCINATION The hepatitis A vaccine was welcomed with enthusiasm upon its introduction in 1995. Western states had long sustained substantially higher rates of Hepatitis A than the remainder of the United States (Figure 1), and Oregon