SEXUAL TRANSMISSION

OF AIDS

Because about two-thirds of people with AIDS become infected through sexual transmission, health officials trying to curb the epidemic have set up guidelines for intercourse they believe reduce the risk, even though much of how the virus works is still a mystery. Their warnings against unsafe sex are based on the premise that HIV is limited in what it can use as a vehicle. Vaginal fluid, semen, and blood provide easy transit for the virus.

In the case of vaginal intercourse without a condom, the HIV spreads between semen and vaginal fluid or menstrual blood.

In anal sex without a condom, the HIV transmission is thought to occur via blood and semen, because the thin-walled rectum contains delicate, easily-ruptured blood vessels and human feces typically contain small traces of blood.

Sharing sex toys such as vibrators may transmit HIV between partners, so use a new condom each time they are traded.

In vaginal, anal, and oral sex, although the person being penetrated is more likely to acquire the disease than the person doing the penetrating, the penetrator is not immune. For both partners, the protection afforded by condoms and dental dams depends on proper application of the right kind of barrier material (see card 66).

Saliva has not been ruled out as an HIV transmitter, but most researchers believe the chances of becoming infected through a passionate kiss, for example, are remote. Oral sex without the use of a condom or dental dam is unsafe, though.

Tears have been found to contain HIV, but no cases are known of transmission by contact with tears.

Next Card 64: SAFER SEX, PART ONE: From Abstinence to Monogamy

SEXUAL TRANSMISSION OF AIDS