By Rob Stein
Washington Post Staff Writer
Tuesday, July 29, 2003; Page A01

The number of Americans developing AIDS appears to be rising again for the first time in 10 years, federal health officials reported yesterday.

AIDS cases increased 2.2 percent in 2002, the first apparent rise since 1993, according to preliminary data from the federal Centers for Disease Control and Prevention in Atlanta.

If the final analysis of the national data collected annually by the CDC confirms the increase, it could mark a turning point in the AIDS epidemic in the United States. The epidemic had appeared to be stabilizing because of years of intensive safe-sex campaigns and the introduction of powerful anti-viral drugs that help prevent HIV-infected people from developing AIDS.

The cause of the apparent increase was unclear. Experts speculated that it could be a combination of factors, including a rise in HIV infections among young gay men in recent years, an increase in people who are failing to respond to the new treatments, and state budget problems, which could be limiting access to care for HIV-positive people who are poor.

In any case, the numbers indicate "the AIDS epidemic in the United States is far from over," said Harold Jaffe, director of the CDC's National Center for HIV, STD and TB Prevention.

The incidence of AIDS increased steadily through the 1980s and into the 1990s, reaching a peak of 80,010 cases in 1993. With the advent of combinations of potent anti-HIV drugs, the numbers had declined every year since. But, according to the preliminary analysis, the number of new AIDS diagnoses increased from 41,227 cases in 2001 to 42,136 cases in 2002 -- a 2.2 percent rise.

In the past few years, there has been evidence that unprotected sex, sex with multiple partners and other risky sexual behavior has been increasing among gay men, particularly younger ones, causing the number of new HIV infections to begin to rise again in that group.

"Our biggest concern is what appears to be a resurgent epidemic in gay men," said Jaffe in a telephone interview before he presented the new data at the National HIV Prevention Conference in Atlanta.

In fact, data from 25 states show the number of new HIV diagnoses among gay and bisexual men increased 7.1 percent from 2001 to 2002, marking the third consecutive year that infections have risen in that high-risk group. HIV diagnoses among gay and bisexual men have increased by 17.7 percent since they hit a low in 1999.

"I don't think there is any one explanation," Jaffe said. "Some of it may be related to treatment optimism: 'So what if you get infected? You can get treated.' Some of it may be related to the belief that if you are in treatment, you may not transmit the virus. Some may be epidemic fatigue -- being tired of hearing about it.

"I think the most compelling reason is that people aren't scared anymore. If you were a gay man in the 1980s, you were scared. You had a lot of friends who were sick and dying. If you are a gay man today, you don't have a lot of sick peers," Jaffe said.

No parallel increase in HIV infections has been detected in other groups, Jaffe said.

But Thomas J. Coates, director of the AIDS Research Institute at the University of California at San Francisco, said it is too soon for an increase in HIV infections among gay men to have translated into an increase in cases of full-blown AIDS, which takes years or even decades to develop.

A more likely explanation, Coates said, is the sluggish economy, which is causing budget problems for states that fund programs to provide the poor with access to AIDS drugs.

"In this day and age, the reason people progress from HIV to AIDS is they are getting inadequate medical care," Coates said. "People depending on public funds are not getting adequate medical care."

The District recently reported that the city has the highest per-capita rate of AIDS of any major U.S. city -- 119 per 100,000 residents. Experts have speculated that poor access to care could be one reason.

Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, said another contributing factor may be that more people are no longer able to take the new drugs or benefit from them. Some people can't tolerate the side effects. In other cases, the virus becomes resistant to the drugs.

"There are people who are undergoing treatment failure," Fauci said.

Researchers will do additional analysis to confirm the increase and to determine whether the new cases are occurring largely among gay men or another group, Jaffe said.

On the positive side, the number of deaths from AIDS continued to decline in 2002, dropping 5.9 percent, Jaffe said.

But that decrease represents something of a slowdown in the decline in deaths, which dropped dramatically because of the introduction of powerful new treatments in the mid-1990s.

During a briefing for reporters yesterday, the CDC's Ronald O. Valdiserri, who is co-chair of the conference, called the increase in infections among gay men "very, very troubling." He said the "findings suggest that the dramatic progress against AIDS . . . is beginning to plateau."

An estimated 850,000 to 950,000 Americans are infected with HIV, but only about a quarter of them are aware that they are HIV-positive, according to the CDC.

Researchers presented a variety of data suggesting that more than two decades into the epidemic, safe-sex efforts remained inadequate in many ways.

One study found only 6 percent of HIV-infected patients at 16 federally funded clinics were counseled on the safety of specific sexual activities. Another study found that a significant proportion of men surveyed at a bathhouse in Los Angeles who reported having sex in a public place did not realize they were HIV-positive.