Conference Focuses on Hope Against HIV, AIDS
Friday, August 18, 2006
TORONTO, Aug. 17 -- The AIDS epidemic in India, good news and bad news out of Africa, and novel drugs on the horizon were topics of research presented in the "late-breaker" sessions of the 16th International AIDS Conference on Thursday.
Here is a brief summary:
The most common way of estimating HIV infection rates in the developing world is to test pregnant women in public clinics and men at venereal-disease clinics for the virus. These are accessible samples of reproductive-age adults. Epidemiologists use those rates, after certain adjustments, to calculate a population-wide estimate.
But how accurate is this method? A team of Indian researchers tried to answer that for one district of Andhra Pradesh, a state in south India.
They tested a random sample of about 14,000 people ages 15 to 49. They adjusted for certain high-risk groups that were under-sampled (such as prisoners) and came up with an estimate of about 47,000 HIV-infected people in the district. The previous estimate was about 113,000 -- almost 2 1/2 times as high.
The "population-based" method found higher HIV prevalence in lower socioeconomic groups. The 25 percent of pregnant women who used public prenatal clinics were more likely to come from lower-income households. That was also true of the men who were treated for venereal infections at the "sentinel" clinics. Together, those samples produced inflated estimates for the whole population.
India has been thought to have 5.2 million infected people (out of 40 million worldwide). Based on the new study, this estimate "needs substantial downward revision," said Lalit Dandona of the Administrative Staff College of India in Hyderabad, who headed the new survey.
Whether that is true of Africa, where researchers also rely heavily on prenatal clinics for data, is unknown. But several countries there that have introduced slightly more representative sampling have come up with lower prevalence estimates in the past two years.
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When American AIDS patients began taking a cocktail of antiretroviral drugs in 1996, death rates plummeted.
Now, that is happening in Africa.
Researchers have been following a sample of HIV-infected people in Entebbe, Uganda, since 1995. In 2003, the drugs became available.