Epidemiologic characteristics of blood donors with antibody to human immunodeficiency virus: Thailand.

Of 782,190 volunteer blood donors in Bangkok and nearby areas, who were screened for infection with human immunodeficiency type 1 (HIV-1) from January 1988 through December 1992, 3,219 tested positive on both enzyme immuno assay and Western blot assay. The identification variables of the donor were collected. The majority of HIV seropositive blood donors were male. The average age (median) of HIV seropositive was 26-29 years all through 1988-2992. The prevalence of HIV seropositive in male donors was higher than that in females. HIV seropositivity was confirmed in blood donations from first-time male donors in this study during 1988-1992. This rate has increased progressively from 0.87/1,000 in 1988 to 15.95/1,000 in 1992 with much higher rates in repeat donors. The repeat male donors increased from 0.77/1,000 in 1988 to 5.26/1,000 in 1991 and since then showed a decreased rate to 3.93/1,000 in 1992. Female donors were infected with HIV more frequently with the prevalence by sex ratio M:F rising from 27:1 in 1988 to 6.6:1 in 1992. Comparing the seropositive rate between first time and repeat female donors, the results showed an increase in rate from 0.11/1,000 in 1990 to 2.02/1,000 in 1992, but essentially the same rate in report donors. A majority of HIV seropositive blood donors (1990-1992) lived in Bangkok (42-49%) and among those who lived in one eastern province (Samut Prakan), 90-93% lived in the industrial areas. Of those who lived in Chon Buri Province, 73-88% lived in Sattaheep District, which is a naval base.