Epidemiology of hemorrhagic fever with renal syndrome in endemic area of the Republic of Korea, 1995-1998

We conducted an epidemiologic study to understand temporal and spatial patterns of hemorrhagic fever with renal syndrome (HFRS) in the Republic of Korea (ROK). We estimated the incidence among civilians in endemic areas through the active surveillance system during the major epidemic periods, from September to December, between 1996 and 1998. We also estimated the prevalence among Korean military personnel from 1995 to 1998. In addition, we assessed seroprevalence, sub-clinical infection rate, and vaccination rates in both civilians and military personnel. The incidence in civilians ranged from 2.1 to 6.6 per 100,000 person-months. The annual prevalence in the military personnel was 40-64 per 100,000 military populations, and remained generally constant throughout the study period with seasonal variation. This is the prospective epidemiologic data set on HFRS in the ROK since the inactivated Hantaan virus vaccine was licensed for use in the late 1990s. These results will be invaluable in establishing a national immunization program against HFRS.