Use of a cheap, commonly-prescribed antibiotic dramatically reduced the death toll among African patients whose immune systems had been ravaged by the AIDS virus, says a paper appearing on Monday.
The drug, co-trimoxazole, marketed as Septrim, Bactrim and other brands, is widely used to combat pneumonia and ear and urinary tract infections and has also been found to have some antimalarial properties.
The investigation covered 3,179 people in Uganda and Zimbabwe who were started on a course of antiretroviral therapy (ART) and whose counts of CD4 immune cells were lower than 200 cells per microlitre.
Among those given co-trimoxazole alongside the anti-HIV drugs, the risk of dying during the first three months fell by 59 percent compared to those who were not on the antibiotic.
At the 72-week stage, the reduced risk of mortality still persisted, although it evened out to 35 percent overall.
In addition, co-trimoxazole cut frequency of malaria by 26 percent.
These benefits, together with the very low side effects, suggest doctors in Africa should also prescribe co-trimoxazole at the early stage of treatment for HIV, says the paper, published online by The Lancet.
"Co-trimoxazole prophylaxis (combined with anti-HIV treatment) is cost-effective and has a substantial public health effect," says the study.
"Our results reinforce WHO (World Health Organisation) guidelines and provide strong motivation for provision of co-trimoxazole prophylaxis for at least 72 weeks to all adults starting combination ART in Africa."
The human immunodeficiency virus (HIV) penetrates and destroys key cells in the immune system, paving the way to AIDS, when the body becomes vulnerable to a host of opportunistic diseases.
Sub-Saharan Africa had 22.4 million people living with HIV or AIDS, amounting to two-thirds of the world total of 33.4 million, according to estimates for the end of 2008 released by the UN agency UNAIDS last November.