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U.S. AIDS Cases, Deaths, and HIV Infections Appear Stable

First comprehensive analysis of HIV incidence studies since 1978 suggests gay and bisexual men and injection-drug users continue to face dangerously high rates of infection

DURBAN, SOUTH AFRICA -- Both HIV and AIDS have stabilized in the U.S., indicating a need for expanded HIV prevention efforts and new treatment strategies, according to Helene D. Gayle, MD, MPH, Director of the National Center for HIV, STD and TB Prevention at the Centers for Disease Control and Prevention.

Dr. Gayle made her remarks at a Journal of the American Medical Association media briefing on HIV/AIDS at the 13th International AIDS Conference.

At the briefing, Dr. Gayle released the latest U.S. data on AIDS cases, deaths, and HIV diagnoses through June 1999. Dr. Gayle also discussed new risk behavior data, and the preliminary results of the first wide scale analysis of HIV incidence studies conducted between 1978 and 1999.

"Despite the dramatic benefits new treatments have had in extending the lives of individuals with HIV, the overall shortfalls of AIDS treatments are becoming increasingly apparent, and HIV infection and risk behavior continues at levels far too high," says Dr. Gayle. "Now more than ever, it is critical that we expand successful HIV prevention programs to bring infection rates down."

AIDS and HIV Data

The latest CDC surveillance data confirm a trend which began in mid-1998. Since July 1998, the number of AIDS cases and deaths diagnosed in the U.S. each quarter (three month period) has remained roughly stable. Dr. Gayle presented data for the first two quarters of 1999, which demonstrate a continued stabilization, with roughly 4,000 AIDS deaths and 10,000 AIDS cases diagnosed each quarter. Prior to 1998, deaths and cases had been declining dramatically since the availability of highly active antiretroviral treatment (HAART).

Dr. Gayle says that lack of progress in further reducing AIDS cases and deaths is likely due to several factors, including: treatment failure; having already reached most people who are susceptible to treatment; the lack of early testing and treatment for some; and difficulty adhering to new treatment regimens. Other CDC data to be presented in Durban will show that a minority of patients on combination therapy benefit for more than a year from HAART, and that patients are having to switch drug regimens frequently to maintain efficacy.

Dr. Gayle also presented data demonstrating that HIV and AIDS diagnoses among young people (13-24 years of age) in 25 states remained stable through June 1999. HIV trends can only be examined in these 25 states who have had HIV reporting for at least five years. Because diagnoses in young people represent recent infections, these data suggest no significant change in the level of new HIV infections. CDC estimates that 40,000 Americans continue to become infected each year.

HIV Risk

A new CDC analysis of data from several large-scale national surveys conducted in the U.S. from 1987 through 1998 was released today. Findings show that a minimum of 2 to 4 percent of the U.S. adult population, or roughly 4 to 5 million people, remain at high behavioral risk for HIV infection. The study defined high risk behavior as: having six or more sexual partners in the last year; having sex with people known to be HIV-infected; exchanging sex for money or drugs; using crack cocaine; injecting drugs during the past 3 years; and male-to-male sexual contact.

The analysis also indicated that while condom use has increased since the 1980's, only 40 percent of unmarried people, and only 23 percent of drug users, report using condoms. And while prevention programs have helped to increase the number of injection drug users using clean needles, roughly 20 percent continue to share needles.

The report found that the level of HIV testing has increased substantially, with roughly 40 percent of the population overall having been tested. Most importantly, the data suggest that more than 70 percent of people at risk have been tested.

HIV Infection Analysis

The first wide scale analysis of HIV incidence studies from 1978 to 1999, compiled by CDC epidemiologist, Dr. Vu Minh Quan, also demonstrated some disturbing trends. The analysis, which examined 83 studies of new HIV infections in different populations, indicates that infection rates continue to be troublingly high in some populations, especially gay and bisexual men.

Infection rates among gay and bisexual men in several cities dropped precipitously after the intense prevention efforts in the 1980s. Yet, over the last decade, studies suggest that infection rates among gay and bisexual men have remained roughly stable, with rates of new infection generally averaging from 1 to 4 percent, depending on the group of men studied. Among particularly high risk populations (e.g. those being treated in STD clinics), much higher levels of infection have been documented. For example, the most recent CDC multi-state study of HIV-incidence found that roughly 8 percent of gay and bisexual men attending STD clinics were being infected annually, with rates as high as 11 percent among African-American gay and bisexual men. Gay and bisexual men in that study were 17 times more likely to be infected than heterosexuals.

Among injection drug users (IDUs), incidence appears to have peaked in the early 1990s (with documented incidence of between 10 and 14 percent). Since that time, incidence has dropped dramatically, falling to levels of less than 2 percent in recent years. Incidence rates varied greatly depending on location of the study and access to substance abuse treatment, with incidence highest in the Northeast and among out-of- treatment IDUs.

According to Dr. Gayle, the greatest declines have been seen in cities such as New York, where successful efforts have been implemented to provide substance abuse treatment, HIV prevention counseling and testing, risk reduction programs, and access to sterile needles. HIV incidence in New York City declined from between 5 percent and 14 percent in the late 1980s to less than 2 percent a decade later.

"While we are pleased that we have been able to maintain progress and prevent increases in HIV infection in recent years, we are allowing far too many infections to continue," says Dr. Gayle. "We have the tools to essentially stop the U.S. epidemic. What we need is the will and the resources to do it."

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Editor's Note: Statements made in this release and at the media briefing are strictly the opinions of the presenter and do not necessarily reflect the views of JAMA or the American Medical Association.

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