The Other Dangers of Close Encounters

While the publicity has focused on AIDS during the past few years, several other sexually transmitted diseases are quietly spreading their own net of contagion. Some old scourges, like syphilis, are making comebacks, and more recently recognized infections, such as genital herpes and chlamydia, are moving swiftly through the population. The extent of the epidemics is unknown, since only a fraction of the cases are reported to health officials. Experts think at least 25 STDs strike millions each year, primarily teenagers and young adults.

The STDs cannot be dismissed as a controllable collection of "social diseases." The open genital sores that many STDs cause can be gateways for the AIDS virus. If left untreated, STDs can cause severe consequences, including heart damage and birth defects. Some 7,000 STD-related deaths occur each year in the U.S., many of them in infants born to infected mothers.

Among the most common STDs:

SYPHILIS. The number of reported U.S. cases of syphilis, a bacterial infection that can cause blindness and death, rose 17% last year, to about 101,000. The disease was once prevalent among homosexuals, but the precautions that gays have taken against AIDS have helped combat syphilis as well. But syphilis is racing through the inner cities, driven by the promiscuity of crack addicts.

CHLAMYDIA. This bacterial infection is insidious because it is frequently symptomless, at least initially. Last year, while only about 150,000 cases were reported, experts think as many as 4 million Americans caught chlamydia, often without knowing it. As many as 45% of sexually active teenagers get the infection. Chlamydia may cause 50% of the cases of pelvic inflammatory disease, which can result in abnormal pregnancies and infertility in women.

GENITAL HERPES. Incurable but not deadly to adults, this infection is caused by the herpes simplex virus. The virus lies quietly within the nervous system, then periodically breaks out to cause painful genital sores. Highly contagious, herpes may have infected 20% of sexually active men and women. Most cases apparently go unreported.

GENITAL WARTS. Possibly more common than herpes are the tiny warts caused by the human papilloma virus. Like herpes, the disease cannot be flushed out of the body. The major complication appears to be a higher risk of cervical cancer in women.

GONORRHEA. Though still common, gonorrhea is the one major STD that appears to be pulling back. The reported cases of this bacterial disease fell 10% last year, to some 700,000. That drop probably resulted from life-style changes among homosexuals. However, antibiotic-resista nt strains are appearing more frequently.

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CREDIT: TIME Chart by Cynthia Davis

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