MY Choi, SS Lee, KH Wong

Objectives To determine the prevalence of HIV infection and risk indicators in adolescents of Hong Kong.

Methods Voluntary reporting system and unlinked anonymous screening provide the HIV prevalence of adolescents aged between 13 to 19 in Hong Kong. Risk indicators in adolescents include prevalence of drug-taking behaviours, determined using behavioural studies, and sexually transmitted diseases.

Results As of the end of June 1995, 573 HIV and 148 AIDS cases have been reported. A majority of HIV infected persons were between 30 to 39 years old in male and 20 to 29 in female. Eighteen were aged between 13 and 19. Thirteen had acquired the infection through infusion of blood or blood products where as 4 were through heterosexual and 1 homosexual contact. For the 5 sexually transmitted cases, 3 were female and 2 of them had developed AIDS. To determine the HIV prevalence, 1753 serum samples, 689 urine samples and 18 samples have been obtained from those under the age 20 in selected populations since 1990 using unlinked anonymous screening and no HIV positive specimen detected.

Those who indulge in illicit drug-taking, have multiple sex partners are at high risk of contracting HIV infection. From the data of the government Central Registry of Drug Abuse, the reported number of drug users has been increasing. The number of new addicts aged below 20 had increased in the first half of 1994 to 58.7%. Sixty-six percent of the newly reported addicts had started taking drugs before the age of 19 as compared with 60% in the first half of the year 1993. Through other behavioural studies, however, there has been significant decrease in the injection use (25-30% decrease) and needle sharing (30-60% decrease) from 1991 to 1994. The other important indicator of the risk of HIV infection in the community is the incidence of sexually transmitted diseases. In the past two years, 3.6-4.2% (460-480) of all reported cases in the government social hygiene services was at or below the age of 19 and female cases predominated (57%).

Discussions Although the reported number of HIV infection in adolescents in Hong Kong seems small, high-risk sexual behaviours do exist in this group at a significant level. There is a discrepancy between these observed phenomena.