July 20, 2010
Poverty appears to be the most important demographic factor influencing the spread of HIV among heterosexuals in economically disadvantaged U.S. neighborhoods, suggests a report being presented this week at the 18th International AIDS Conference in Vienna.
The CDC researchers looked at the pattern of HIV infection in 23 urban census tracts in which at least 20 percent of households were below the poverty line, $10,294 for an individual. To isolate the effect of poverty, the scientists narrowed their focus to heterosexuals who did not use injection drugs, a category that describes about 28 percent of the United States' HIV-positive population. The analysis was based on the experience of 9,094 participants in the U.S. National HIV Behavioral Surveillance system in 2006-07.
Overall HIV prevalence in the 23 tracts was 2.1 percent; 2.4 percent among residents below the poverty line. Those who lived in the same poor neighborhoods but had incomes above the poverty level had an HIV prevalence of 1.1 percent. Any HIV prevalence above 1.0 percent defines a generalized HIV epidemic. The analysis by CDC researchers did not find significant differences in the risk of HIV prevalence by race or gender.
"It's epidemiological bad luck," said Dr. Jonathan Mermin, who is director of HIV/AIDS prevention for CDC and who oversaw the study team. "I'm in a community where, when I meet a new [sexual] partner, the chance that they would have HIV is much higher than if I were wealthy and living in another geographical area."
The link between poverty and HIV demands a reconsideration of how to fight the epidemic, said Dr. Carlos del Rio, chair of global health studies within the school of public health at Emory University. He recently conducted a study that found epidemic-level HIV prevalence in certain Atlanta neighborhoods, with 60 percent of the city's cases identified in a downtown area with a high concentration of blacks, IV drug users, and poor people.
"You talk about 'Can we decrease the HIV burden in the United States?' I would say, 'What can we do to decrease poverty in the United States?'" del Rio said.