特集 発展途上国におけるウイルス疾患の現状と対策 １２． 東南アジア地域におけるＨＩＶ／ＡＩＤＳ流行の分子疫学

Abstract

Needle sharing among injecting drug users (IDUs) common practice of prostitution due to poverty unprotected sex (especially among STD patients) and most of all lack of education have contributed to the HIV/AIDS epidemics in Thailand and India. The first reported case of AIDS in Thailand was a foreign male homosexual in 1984. Since 1988 needle sharing among IDUs especially in Bangkok has accelerated the HIV epidemic and 40% of IDUs show elevated HIV antibody titers. 40-50% of lower-class prostitutes in northern Thailand are HIV-positive. The epidemic is spreading to the general population as well (0.5% of the total population is infected). HIV-1 in Thailand is either of subtype A or B with subtype A being the more prevalent type. Subtype A (African) risk groups include female prostitutes (91.7%) male prostitutes (75%) STD patients (81.8%) spouses of infected persons (100%); IDUs (76%) belong to the subtype B (AmEu) risk group. More than 1 million people in India are said to be infected with HIV. According to the World Health Organization in the Bombay area alone 250000 people are infected and the majority of them are prostitutes. The antibody-positive rate is 30%. Moreover 4% are infected with HIV-2. 20% are double-infected with both HIV-1 and HIV-2. The HIV-1 prevalent in Bombay is akin to HIV-1 NOF of South Africa and ZAM20 of Zambia. It also belongs to subtype C. The HIV-2 found in India is believed to be of West African origin. There is great concern that the epidemic will spread to the rest of Asia including Japan where some of the residing 60000 Thai women have been found to be infected with HIV-1 subtype A.