Microbicides and HIV prevention
Currently, there are an estimated 15,000 new infections that occur on a daily basis despite availability of ARVs since 1996. Between 2003 and 2005, for each new person who got treatment for HIV, about 10 people became infected. This underscores the need for effective preventive methods.Male condoms, despite being able to prevent more than 80% of HIV infections when used correctly and consistently, are not acceptable to most male clients.Women in many areas where HIV had reached epidemic proportions are unable to negotiate its use. The female condom has similar limitations, as it also requires the cooperation of the male partner, in addition to being poorly accessible and expensive. Hence, efforts need to be stepped up to find a method which will empower women to take charge of HIV prevention. A microbicide is a substance that can be used to prevent (or at least significantly reduce) the heterosexual transmission of HIV and other sexually transmitted infections, when applied vaginally or rectally.Microbicide agents come in different preparations and/or formulations. The first generation microbicides are gels and creams; whereas subsequent generations include vaginal rings, films, sponges, gels with barrier devices and suppositories, and work by altering the environment of the genital tract to make it unsuitable for the virus to act and survive. Antiretroviral agents, being specific in their mode of action by attacking the HIV, are part of the third generation microbicides. Another possibility is to combine different agents with different mechanisms of action e.g. combining an agent altering the genital tract pH and that inhibiting fusion or entry of the virus to the target cell.
Obstetrics & Gynaecology Forum Vol. 17 (3) 2007: pp. 71-73