For years official records of Cambodia’s HIV/AIDS rate have been inflated, according to the Ministry of Health, which this month released what it said is its most comprehensive report to date, showing that the rate of the deadly disease was significantly lower than initially thought.
Blood samples taken in 1999, 2000 and 2002 that originally tested positive for HIV were recently found to have in fact been negative, said Heng Sopheap, chief of the National Center for HIV/AIDS, Dermatology and STD Control’s prevalence unit.
Last year the Ministry of Health and the University of California at Los Angeles re-tested 3,599 blood samples taken during those three years from Cambodian sex workers and police, Heng Sopheap said.
They found that 6.1 percent to 9.7 percent of those samples initially thought positive were actually negative, he said in an interview last week.
Because of the erroneous results, the ministry adopted new methods of testing and new quality control measures, Heng Sopheap said. In its most recent report, titled “HIV Sentinel Surveillance 2003: Results, Trends, and Estimates,” released Dec 3, the ministry readjusted the national HIV/AIDS prevalence rate in 2002 to 2.1 percent from its original figure of 2.6 percent.
Using the new methodology, it reported that in 2003 that figure dropped again, and now 1.9 percent of Cambodians age 15 to 49 are estimated to be living with the virus that causes AIDS.
“Based on the results of the quality control, you can re-adjust all the prevalence rates that were reported in the previous years,” said Dr Tia Phalla, National AIDS Authority secretary-general.
The new quality control measures implemented in 2003 involved re-testing samples found positive by Phnom Penh’s National Institute of Public Health and by the US Centers for Disease Control in the state of Georgia, Heng Sopheap said. Some 1.2 percent of the samples brought to the CDC were found “incorrectly identified as positive or negative,” he said.
Last week, however, the UN Children’s Fund reported that Cambodia still has a 2.6 percent prevalence rate. Rodney Hatfield, Unicef representative in Cambodia, said the discrepancy could be “because the data that Unicef has used is not [as] up to date as the government’s.” But, he said, “I think there is not full data on people who go to private clinics.”
Cambodia’s HIV/AIDS rate “is still considered the highest prevalence compared to neighboring countries like Vietnam, Thailand and Laos,” he said.
(Additional reporting by Yvonne Lee)
