Condoms and HIV transmission [editorial]

Few prospective studies show that condoms effectively reduce HIV transmission. A meta-analysis of retrospective data indicates that consistent use of condoms among partners of HIV-infected people reduces the risk of HIV transmission by about 69%. For 24 months the European Study group followed heterosexual couples in which 1 partner was HIV positive and the other was initially HIV negative. It found that about 50% of the couples continued to have unprotected sexual intercourse despite repeated counseling to practice safer sex. A considerable risk of infection existed for the couples who did not use condoms consistently (4.8/100 person-years; cumulative incidence of 12.7). No seroconversion occurred among the 124 couples who always used condoms. The researchers could not exclude the possibility of a transmission rate as high as 1.5/100 person years among consistent condom users however because the carefully followed cohort was not large enough. These results confirm that compliance with an intervention is as important as the efficacy of the method. The study did not explain why some people practice risk reduction strategies while others do not. Infectivity differs from 1 person to another and in 1 person over time. Consistent condom use in developing countries particularly Africa and Asia can limit the AIDS epidemic only if the issues of acceptability supply and cost can be surmounted. The higher prevalence of untreated sexually transmitted diseases (STDs) in developing countries may contribute to a higher rate of HIV transmission. Individuals need choices to reduce their risk of HIV infection but each method needs to be effective. Methods include condom use programs to control STDs development of vaginal microbicides development of vaccines and behavioral interventions. The European study boosts our confidence that condoms are truly effective but it also tells us that more is needed to improve worldwide efforts to develop and implement effective methods to prevent HIV transmission.