An expanding HIV epidemic is inevitable in the Philippines as limited condom use and increasing levels of casual sex spur the spread of the AIDS-causing virus, researchers said.
New cases of HIV in the nation of 100 million people, which has one of Asia's lowest infection rates, jumped 58 percent last year to 835 after tripling between 2003 and 2008, Anna Farr and David Wilson wrote in the Journal of the International AIDS Society Thursday.
"This suggests that the epidemic could be approaching a large expansion phase," Farr and Wilson, researchers from the Sydney-based National Centre in HIV Epidemiology and Clinical Research, wrote. "An expanding HIV epidemic is likely to be only a matter of time."
The average age of diagnosis has fallen to 29 from about 36, they said. Fewer than 0.1 percent of adults between the ages of 15 and 49 in the Philippines were infected with HIV as of 2007, according to United Nations estimates published in 2008. That compares with 1.4 percent in Thailand, 0.8 percent in Cambodia and 0.5 percent in Vietnam and Malaysia.
The Philippines, a majority Roman Catholic nation, has Asia's lowest documented rate of condom use, Farr and Wilson wrote.
"The current government's seemingly unwilling attitude to promote wide condom use for fear of angering the Roman Catholic Church" has blunted the effect of laws passed in 1998 to curb the spread of HIV, they said.
Farr and Wilson summarized research published between 1989 and 2009 for their report.
The virus is spreading faster as young people have more casual sex and as Filipino workers return home from countries with high prevalence of HIV, the authors said. About one-third of all cases of HIV in the country are attributable to Filipinos who return after working abroad, mainly as seafarers and domestic helpers, the report said.
New infections among men are increasing faster than among women, suggesting an emerging epidemic among gay and bisexual males, Farr and Wilson wrote. That divergence may also reflect differences in testing rates, they said.
About 92 percent of new infections are spread through sex, the report said. Infections through gay and bisexual sex are rising faster than those through heterosexual contact, it said.
The Philippines may have been spared an HIV epidemic so far because of its geographical separation from mainland Asia, low numbers of injecting drug users compared with neighboring nations, a "culture of sexual conservatism," and high rates of male circumcision, which has been shown to reduce the chances of men catching HIV from women, the authors wrote.