MOST anti-retroviral drugs are now considered for research trials seeking to reduce the risk of passing the deadly virus that causes Aids to others, a leading HIV researcher said here on Monday.
Addressing hundreds of delegates attending a Microbi-cide 2010 International conference in the United States of America, Professor Robin Shattock said if ARVs were proved to prevent HIV transmission, they would work as secondary benefit after their primary purpose of improving individuals' health.
"The idea behind this strategy is that ARV treatment reduces viral load and that lowering viral load (below a certain point) may greatly reduce the risk that a person with HIV will transmit the virus," Prof Shattock said.
The relationship between lower viral load and reduced risk of transmission has also been observed in some studies of HIV-positive women breastfeeding HIV-negative children.
"People were already questioning whether universal access to treatment is achievable without significantly reducing the number of new infections. Donors were questioning, too, whether it is sustainable to continue the roll out of treatment across the globe," said Prof Shattock.
He said there was no doubt that HIV prevention, treatment, care and support programmes all needed to be fully funded, supported and rolled out in all possible ways.
Zimbabwe is already conducting trials of common ARVs Truvada and Tenofovir to ascertain whether these drugs can really reduce HIV transmission and South Africa has completed a larger trial aimed at evaluating whether an ARV Tenofovir can reduce the same.
Results of whether the ARV as prevention strategy works will only be known in July this year during the International Aids Conference to be held in Vienna, Austria. The results under review are those from the South Africa trial.
Other countries evaluating whether this strategy works are Brazil, India, Thailand and USA.
Prof Shattock said although this strategy might make a positive impact on rates of new HIV infections, challenges of ARV availability remained paramount in some settings especially developing countries.
"Current gaps in coverage of ARVs for people who are clinically eligible for them, low rates of HIV testing, additional scientific questions about the exact relationship between HIV viral load in the blood and risk of transmission and lack of consensus around the best time for individuals to begin treatment are the main impediments in the strategy," Dr Shattock said.
In Zimbabwe, according to the national HIV estimates for 2009, close to 350 000 people living with HIV and Aids are in desperate need of ARVs. The Zimbabwe Aids Activists Union (ZHAUU) said HIV- positive people in need of ARVs were still waiting for months before they were put on the ARV Government programme.
Although steadily declining, Zimbabwe's HIV prevalence rate remains one of the highest in the world. Current statistics show that the prevalence rate among sexually active population is 37,1 percent, hence the need for scientists to come up with more HIV prevention studies.
The M2010 conference is the first microbicides conference to talk about HIV prevention technologies in a broader context. It also includes Pre-Exposure Prophylaxis (PrEP).
HIV and Aids activists attending the conference called for more and better HIV researches to combat the pandemic.
South Africa's national co-ordinator for the Women's Rights Campaign at the Treatment Action Campaign, Ms Nomfundo Eland, said activism without research was nothing. She also called for interventions that protected women from acquiring HIV. According to global statistics, nearly half of all people living with HIV are women.
In Africa, about 60 percent of new infections are acquired by women and girls.
The sixth biennial meeting of the International Microbicide Conference ends today.