In 1981, scientists in the United States and France first recognized the Acquired Immune Deficiency Syndrome (AIDS), which was later discovered to be caused by a virus called the Human Immunodeficiency Virus (HIV). HIV breaks down the body's immunity to infections leading to AIDS. The virus can lie hidden in the body for up to 10 years without producing any obvious symptoms or before developing into the AIDS disease, and in the meantime the person can unknowingly infect others. Currently, an estimated 40 million people worldwide are HIV carriers, and three million a year are dying of AIDS.

HIV lives in white blood cells and is present in the sexual fluids of humans. It's difficult to catch and is spread mostly through sexual intercourse, by needle or syringe sharing among intravenous drug users, in blood transfusions, and during pregnancy and birth (if the mother is infected). Using another person's razor blade or having your body pierced or tattooed are also risky, but the HIV virus cannot be transmitted by shaking hands, kissing, cuddling, fondling, sneezing, cooking food, or sharing eating or drinking utensils. One cannot be infected by saliva, sweat, tears, urine, or feces; toilet seats, telephones, swimming pools, or mosquito bites do not cause AIDS. Ostracizing a known AIDS victim is not only immoral but also absurd.

Most blood banks now screen their products for HIV, and you can protect yourself against dirty needles by only allowing an injection if you see the syringe taken out of a fresh unopened pack. The simplest safeguard during sex is the proper use of a latex condom. Unroll the condom onto the erect penis; while withdrawing after ejaculation, hold onto the condom as you come out. Never try to recycle a condom, and pack a supply with you, as it can be a nuisance trying to buy them on short notice.

HIV is spread more often through anal than vaginal sex, because the lining of the rectum is much weaker than that of the vagina, and ordinary condoms sometimes tear when used in anal sex. If you have anal sex, only use extra-strong condoms and special water-based lubricants, since oil, Vaseline, and cream weaken the rubber. During oral sex you must make sure you don't get any semen or menstrual blood in your mouth. A woman runs 10 times the risk of contracting AIDS from a man than the other way around, and the threat is always greater when another sexually transmitted disease (STD) is present.

The very existence of AIDS calls for a basic change in human behavior. No vaccine or drug exists that can prevent or cure AIDS, and because the virus mutates frequently, no remedy may ever be totally effective. Other STDs such as syphilis, gonorrhea, chlamydia, hepatitis B, and herpes are far more common than AIDS and can lead to serious complications such as infertility, but at least they can usually be cured.

You should always practice safe sex to prevent AIDS and other STDs. You never know who is infected or even if you yourself have become infected. It's important to bring the subject up before you start to make love. Make a joke out of it by pulling out a condom and asking your new partner, "Say, do you know what this is?" Or perhaps, "Your condom or mine?" Far from being unromantic or embarrassing, you'll both feel more relaxed with the subject off your minds, and it's much better than worrying afterwards if you might have been infected. The golden rule is safe sex or no sex.

An HIV infection can be detected through a blood test, because the antibodies created by the body to fight off the virus can be seen under a microscope. It takes at least three weeks for the antibodies to be produced and in some cases as long as six months before they can be picked up during a screening test. If you think you may have run a risk, you should discuss the appropriateness of a test with your doctor. It's always better to know if you are infected so as to be able to avoid infecting others, to obtain early treatment of symptoms, and to make realistic plans. If you know someone with AIDS, you should give them all the support you can (there's no danger in such contact unless blood is present).