A new study says universal access to AIDS drugs in developing countries could increase HIV infection rates if they are not accompanied by prevention measures, such as patient education.
Roughly 95 percent of people infected with HIV live in the developing world, where there is a global push by the World Health Organization to get anti-viral therapy to as many patients as possible.
The authors of a study published in the online journal Public Library of Medicine say that everyone who needs anti-AIDS drugs should get them, but they also warn that the therapy may not be as successful as its advocates hope.
The lead author of the study, Rebecca Baggaley of London's Imperial College, says drug treatment in poor countries might not have the desired effect unless there are adequate resources. Ms. Baggaley says the absence of these resources, such as counseling patients about how to prevent spreading HIV, could limit the effectiveness of the WHO campaign.
"And the WHO is envisaging very, very large-scale roll out of anti-retroviral therapy where this kind of infrastructure will not be available, and, therefore, the very long extension of life expectancy [that has occurred] in industrialized countries might not be the same [in developing countries]," she said.
To try to predict various outcomes of anti-viral therapy in resource-poor countries, Baggaley and colleagues at Imperial College developed a model of HIV conditions in Malawi in sub-Saharan Africa.
She says even with AIDS drugs, the model predicts HIV-positive individuals in developing countries are unlikely to do well, because they tend to be diagnosed at a late stage in the disease.
They also face a lack of resources that enable them to monitor their progress, as well as poor nutrition and problems taking the drugs prescribed on a regular basis.
Baggaley says the goal of antiviral therapy in Malawi and other countries is that more people will be diagnosed earlier in the course of the disease. This in turn will enable them to get on the drug regimen earlier, feel better and live longer. But Ms. Baggaley adds that early diagnosis also has consequences.
"This means altogether that actually HIV prevalence increases with antiretroviral therapy," she added. "If we saw an increase in sexual behavior as well, this would increase it even further."
She cited the example of the United States, where the widespread use of antiviral drugs led to an increase in unprotected sexual activity among gay HIV-positive men.
As always, Baggaley says the message of her and other recent studies is that safe sex counseling is an essential part of any AIDS control program.