Nationally, rates average 10-12 cases per 100,000. Rates tend to be higher in the states west and south of the Rocky Mountains. The exact reason for this is unknown. Various epidemiologic comparisons of local and national hepatitis A data can be made. For 1996, the latest year in which comparable data exists, incidence rates in King County for persons greater than 15 years of age were approximately three times the rates for the U.S. population.
King County tends to have a higher proportion of males reported as cases than the national ratio.
Injection drug users are often recognized as a population in which outbreaks occur. Local estimated case rates for this at risk group were 313 per 100,000 in 1997. Efforts are being made to educate the MSM population about the risk of hepatitis A, the behaviors contributing to this risk, and the recommendation for vaccination. A flyer has been developed with MSM as a target audience, and copies of this are available upon request. Proposals have been submitted to local government for supplemental funding to support educational and vaccination strategies for this population.