Community-Wide Treatment as Prevention.
A newly published study finds that as more HIV infected members of a community members are put on treatment, fewer people become infected with the virus within that community. The community “treatment as prevention” study was published this week in the prestigious journal Science.
Researchers from the Africa Centre for Health and Population Studies used HIV surveillance data collected in KwaZulu-Natal, a poor rural area of South Africa where about one out of three have HIV. Over time, about 20,000 individuals among 228,000 area residents were put on HIV treatment.
The study found that for each percentage point increase for those in the province on HIV treatment, there was a significant decrease in HIV transmission community-wide.
When HIV treatment coverage reached 20 percent of the infected population, there was a 22 percent decline in HIV infections said study researcher Frank Tanser, PhD, of the Africa Centre for Health and Population Studies in South Africa. “In communities where HIV treatment achieved 30 percent, the individuals’ HIV acquisition was 38 percent less likely.”
Conversely, in areas where access to HIV treatment coverage was low there were no such reductions in new infections.
The results have implications for HIV at-risk communities well beyond AIDS ravaged Africa. Here in the United States, greater HIV treatment access should achieve the same “Treatment as Prevention” reductions of new transmissions in those affected communities.
“These findings are extremely important,” said Paul De Lay, deputy executive director, Programme, Joint United Nations Programme on HIV/AIDS.
“The results give clear evidence that HIV incidence is reduced as a result of high coverage of antiretroviral therapy,” added Dr. Tanser.
The research also confirms the results of the study that proved the concept of Treatment as Prevention or TasP. Declared the 2011 breakthrough of the year by the Journal Science, the New England Journal of Medicine study found that effectively treating HIV infection provides an HIV prevention bonus of reducing the spread of the virus for couples where one partner in HIV infected and the other is not. The groundbreaking study, known as HPTN 052, found that if an HIV-positive person stays on antirviral therapy, the risk of transmitting the virus to their uninfected sexual partner can be reduced by 96 percent.
Followup studies to HPTN 052 have found that Treatment as Prevention, if implemented on a world wide scale, would not only be cost-effective, it could save global health programs money over the long term.
Commenting on those findings, Dr. Rochelle Walensky of the Harvard Center for AIDS Research said that regardless of the country, TasP is a triple winner: “HIV-infected patients do better, their partners are protected and it is very cost-effective.”
Along with the study measuring the community-wide benefit of TasP, Science published another KwaZulu-Natal study showing that providing antiviral therapy increased overall life expectancy by more than ten years.
Myron Cohen, who headed the original HTPN 052 TasP study, called the KwaZulu-Natal studies terrifically important.
Cohen told NPR, “I think this is a home run, by any nature, and it’s teaching us something. You know, you don’t have to treat everybody in order to see a community benefit.”
The studies noted above demonstrate how Treatment as Prevention will be invaluable tool for ending the epidemic in community hot-spots, whether they be in Africa, or urban and rural North America.