Experts Fear Resurgence of HIV Infection

The numbers of AIDS deaths and new HIV infections in the United States have remained stable for the second year in a row, public health authorities will announce today. But increases in risky behaviors and growing infection rates among the young are setting the stage for a resurgence of the disease, officials cautioned.

An estimated 16,000 Americans died of AIDS last year and 40,000 became HIV-positive, according to the newest figures compiled by the Centers for Disease Control and Prevention. But as many as 5 million Americans engage in sexual and drug behaviors that place them at high risk of contracting the virus, according to new studies released in Durban, South Africa, in advance of Sunday’s start of the 13th International AIDS Conference.

A separate study of more than 3,400 young gay men found that 7.2% of them were HIV positive, with the rate among young black gay men soaring to 19%. In Los Angeles, the rate for young gay men was 8.3%, while in New York City, the incidence was 12.2%. More than 80% of those who were infected did not know it, according to CDC researchers.

Data released last week showed that the rate of new HIV infections in San Francisco grew by more than 60% last year as a result of increases in sexually risky behavior.

“HIV infection and risky behavior continue at levels far too high,” said Dr. Helene Gayle, director of CDC’s National Center for HIV, STD and TB Prevention. “Now, more than ever, it is critical that we expand successful HIV prevention programs to bring infection rates down.”

Health officials say that, overall, as many as 900,000 Americans may be infected.

In other pre-meeting news, researchers from the National Institutes of Health reported that adding an anti-cancer drug called interleukin-2, or IL-2, to cocktails of AIDS drugs can substantially improve restoration of the immune system.

And the German drug company Boehringer Ingelheim said Friday that it will donate the anti-AIDS drug nevirapine to developing countries to help reduce mother-to-child transmission of the AIDS virus. A report in last month’s Lancet said that nevirapine was the most cost-effective, efficacious and easily administered drug for that purpose.

The number of new AIDS cases in the United States peaked in the first quarter of 1993, then began a sharp decline as a result of growing efforts focused on prevention programs. AIDS deaths peaked two years later, and then also began to drop as cocktails of anti-AIDS drugs--including the new protease inhibitors--were introduced to control infections.

But both rates have remained roughly the same since July 1998, Gayle said. She attributed the lack of further progress to treatment failures caused by viral resistance to the drugs; treatments’ having already reached most people who can benefit; the lack of early testing and treatment for some victims; and the difficulties of adhering to the complicated treatment regimens.

Another reason is that large segments of the population, at least 2% to 4% of adult Americans, continue to engage in risky behaviors, according to another CDC study. Researchers defined risky behaviors as including: having six or more heterosexual sex partners in a year, having unprotected sex with people known to be HIV-positive, exchanging sex for money or drugs, using injected drugs, and having male-to-male sexual contact.

The study also found that even though condom use has increased during the last two decades, only 40% of unmarried people and 23% of drug users employ condoms.

One of the greatest successes in combating the AIDS epidemic has been in halting HIV transmission among intravenous drug users. The incidence of infections in this group peaked at between 10% and 14% in the early 1990s, but has now fallen to less than 2%. Nonetheless, Gayle noted, at least 20% of such users still share needles, a major risk factor.

In contrast, risks taken by young gay males remain a major problem, as illustrated by the Young Men’s Survey, conducted in six U.S. cities from 1994 through 1998. Researchers went to clubs, bars and other locations regularly visited by young gay men and ultimately enrolled 3,492 males, ages 15 to 22. The men were interviewed and given an HIV test.

The team reports in next Wednesday’s Journal of the American Medical Assn. that 7.2% of the men were HIV-positive, with the incidence ranging from zero among 15-year-olds to 9.7% among 22-year-olds. Only 46 of the 249 men who tested positive for HIV knew before the test that they were infected.

“This rate is alarming when you consider these young men have very short sexual histories,” said Wesley Ford of the Los Angeles County Department of Health Services, who worked on the study.

Moreover, 41% of the youths reported having had unprotected anal sex within the previous six months. The message of safe sex “is not reaching these groups,” Ford added.

Some good news is coming out today, however. In another paper in the medical association journal, Dr. Richard T. Davey and his colleagues at the National Institute of Allergy and Infectious Diseases report on the first studies of IL-2 in patients receiving standard AIDS therapy.

IL-2, a protein produced by white blood cells, stimulates the production of immune system cells called CD4 T-cells, which play a key role in fighting infections by bacteria and viruses. HIV infection sharply reduces the number of CD4 cells, making the victim susceptible to a variety of opportunistic infections.

Davey’s team studied 78 HIV-positive patients receiving cocktails of anti-HIV drugs. Half received IL-2 in addition to those drugs, and half received a placebo. They found that patients receiving IL-2 had a 112% increase in their CD4 counts, while those receiving the placebo had only an 18% increase.

“I’m very heartened” by the response, Davey said.

Even more heartening is the planned donation of nevirapine, trade-named Viramune. Studies in Uganda have shown that one dose of the drug is twice as effective as multiple doses of AZT in preventing HIV transmission by pregnant women.

Researchers projected that using the drug in South Africa alone would prevent as many as 110,000 infant HIV infections over the next five years.

“This offer holds out great hope for many millions of women,” said Dr. Peter Piot, executive director of UNAIDS.

Critics cautioned, however, that an offer earlier this year by five major drug companies to provide AIDS drugs to African nations at reduced prices has been bogged down in squabbling over such issues as how to distribute the drugs in the absence of an effective health care infrastructure. No drugs have actually reached their destinations.

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Stable, for Now

The number of AIDS deaths and new HIV infections in the United States has plateaued, but increases in risky behaviors and growing infection rates among the young may cause a resurgence of the disease, public health authorities say.

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*figures for January through June 1999

Source: Centers for Disease Control and Prevention