HIV infections up sharply among Hong Kong gay men

HONG KONG (Reuters) - Up to a third of gay and bisexual men in Hong Kong may be infected with HIV by 2020 if prevention programs to reduce new infections and promote safe sex fail to work, experts warned.

HIV is primarily passed from person to person in Hong Kong through sex. The number of gay and bisexual men confirmed with the virus has risen sharply every year since 2003.

The figure rose from 50 in 2003 to 67 in 2004, 96 in 2005 and 112 in 2006, while newly confirmed infections among heterosexuals stayed within a range of 110-116 each year.

"If all our actions fail, by 2020 we can have one-third infected in the community. Some of them may go on to infect women," said Wong Ka-hing, consultant for the Hong Kong government's Center for Health Protection.

Rising numbers of gay and bisexual men are becoming infected in many countries, perhaps because of the availability of HIV drugs, which can control the virus but not cure the infection.

Four percent of Hong Kong's gay and bisexual men are HIV-positive and genetic analyses of virus samples found three HIV strains circulating in the local community.

"There are three clusters (of people infected by the three strains) ... we investigated and found common risk factors like a number of people attending the same sex parties, Internet use (to search for sex partners), using recreational drugs, unsafe sex, STI (sexually transmitted infections)," Wong said.

"Not many people (in this community) think safe sex is important. Their condom use (70 percent with casual partners, 40 percent with regular partners) is lower than heterosexual men (80-90 percent with prostitutes)," Wong said.

FASTER TESTS NEEDED

Chen Zhiwei, director of the AIDS Institute, which conducts HIV/AIDS studies in Hong Kong and on mainland China, called for faster testing techniques.

HIV test kits used in Hong Kong search for antibodies to the virus. But Chen said they tend to miss newly infected cases as the body does not start producing anti-bodies until two weeks to a few months after infection.

However, it is during this "window period" that the newly implanted virus is at its most active -- multiplying rapidly and making the person potentially very infectious.

"Early diagnosis is very important. We need to identify newly infected cases, especially among people who are sexually active. Immediately after infection, the viral load is very high, so the chance of transmitting to others is very high," Chen said.

"If we rely on antibody tests, we have to wait for the immune system to kick in. And in the window period, the guy may have transmitted the virus to many people," he told Reuters.

Chen recommended the use of polymerase chain reaction (PCR) tests, which can detect viruses in the blood -- very soon after infection and well before the body starts producing antibodies.

(Editing by Nick Macfie and Paul Tait)