Epidemiology of HIV infection in the Republic of Korea.

Since the first case of human immunodeficiency virus (HIV) infection in the Republic of Korea (ROK) was detected in 1985, 876 HIV-infected patients have been reported, as of December 1998. The male to female ratio was 6.8:1, and 87% of the patients were between 20 and 49 years of age. The major modes of transmission were sexual contacts, accounting for 86% of the cases (65% heterosexuals and 21% homosexuals). Transmission through blood and blood products accounted for 28 cases (3.2%), and vertical transmission for one case. No cases among intravenous drug abusers were reported. The seroprevalence among the blood donors was approximately one in 100,000. Subtypes A, B, C, D, E, and G of HIV-1 have been introduced into the ROK, and subtype B is the most predominant subtype. The frequency of the a deletion in the CCR5 gene, a coreceptor of HIV-1, was less than 1% among Koreans.