<unk>  are pharmacologic agents and chemical substances that are capable of killing or destroying certain microorganisms that commonly cause human infection (for example, the human immunodeficiency virus).<unk>  are a diverse group of chemical compounds that exert their activity by a variety of different mechanisms of action. Multiple compounds are being developed and tested for their microbicidal activity in clinical trials.<unk>  can be formulated in various delivery systems including gels, creams, lotions, aerosol sprays, tablets or films (which must be used near the time of sexual intercourse) and sponges and vaginal rings (or other devices that release the active ingredient(s) over a longer period). Some of these agents are being developed for vaginal application, and for rectal use by those engaging in anal sex. Although there are many approaches to preventing<unk><unk><unk>  in general (and HIV in particular), current methods have not been sufficient to halt the spread of these<unk>  (particularly among women and people in less-developed nations). Sexual abstinence is not a realistic option for women who want to bear children, or who are at risk of sexual violence. In such situations, the use of<unk>  could offer both primary protection (in the absence of condoms) and secondary protection (if a condom breaks or slips off during intercourse). It is hoped that<unk>  may be safe and effective in reducing the risk of HIV transmission during sexual activity with an infected partner.
Microbicides for sexually transmitted diseases
Fungicide
Long-acting reversible contraception
Amebicide
Herbicide
Rectal microbicide
Heat-based contraception
Abstinence, be faithful, use a condom