By Peter Freiberg

Horror stories about AIDS have become commonplace. But the grim statistics in a recent U.N. report are enough to shock experts and the public alike.

The report found that AIDS cases have been underreported worldwide by as much as one third (see chart), and that by the year 2000, 40 million people will be living with HIV. Psychologists on the front lines of fighting the disease say the new projections are especially tragic because there is nothing inevitable about the course of AIDS: Prevention, they say, has been shown to work.

?This out-of-control epidemic is unnecessary,? says psychologist Thomas Coates, PhD, a longtime AIDS prevention researcher and the director of the new AIDS Research Institute at the University of California-San Francisco, a multidisciplinary facility.

?The only reason it?s happening is not because of a lack of scientific knowledge,? says Coates. ?It?s happening because not enough money is being spent and because of a lack of political will to implement strategies that we know are effective.?

Coates says psychologists have been pre-eminent in prevention, which he says has been both ?good and bad??good because it has allowed the application of solid scientific principles to the prevention effort, bad because psychologists? focus ?has probably been a bit too much on the individual, and not enough on?political systems and policy systems.?

Today more psychologists are working to address AIDS prevention on both fronts.

There is hope
While the U.N. report?s findings had some dizzying conclusions (see sidebar below), it is not all gloom. It notes, for example, that while most new infections worldwide are in people age 15 to 24, educational programs are lowering the number of new cases in some countries.

In Uganda, for example, educational efforts have led young people to adopt safer sexual behavior: They are initiating sex later, having sex with fewer partners, and using condoms more than was common a decade ago. The report also singles out Thailand where prevention efforts have led to a fall in new infections. Efforts there seek to increase condom use among heterosexuals, boost respect for women, discourage men from visiting sex workers and offer young women better educational and job prospects to discourage their entry into commercial sex.

In the developed world, Coates points to Australia, which he says has ?virtually no epidemic,? as a model of prevention. With substance-abuse treatment on demand, explicit sex education for young people and close collaboration with the gay community to promote safer sex, says Coates, Australia reports 500 new HIV infections a year in a country of more than 20 million people.

Success in these countries, Coates says, is due to their willingness to make AIDS a national priority, to implement proven prevention programs?such as sex education and needle exchange?despite political opposition and to earmark substantial prevention funds. But large-scale prevention efforts in the developing world will have to be paid for by the developed world?which so far shows no inclination to allocate enough funds, Coates says.

?We have to be willing to spend the money,? he says. ?The developing world doesn?t have it.? In one example of international cooperation, the U.S. Agency for International Development, the National Institute of Mental Health, the World Health Organization and the U.N. Program on HIV/AIDS co-sponsored a three-country study that Coates helped conduct. The study enrolled 4,300 people in Kenya, Tanzania and Trinidad to determine whether investment in voluntary counseling and testing is a good use of prevention dollars to bring about behavior change. His results show it is. In the study, individuals and couples were given either HIV counseling and testing?a minimum of one pre- and one post-test counseling session?or basic health information?a videotape with culturally appropriate information on HIV. At a six-month follow-up, those who had received counseling and testing, says Coates, reported significant decreases in risky sexual behavior, compared with participants who received only basic health information.

In another study that will raise policy questions, the AIDS Research Institute will soon undertake a study of the implications on the spread of HIV of ?postexposure prevention??providing people newly exposed to HIV with medication that may prevent them from getting infected and intensive counseling to help them reduce exposure in the future. Participants in this study, funded by the National Institute of Allergy and Infectious Diseases, will include 500 people from the San Francisco area who report exposure to HIV in the previous 72 hours. Previous research has shown that health-care workers who receive antiviral therapy for a month after being infected by contaminated needles are 81 percent less likely to be infected with HIV. The question, says Coates, is whether this finding can be applied in the sexual arena. The concern, he says, is that ?this could be a morning-after kind of thing?: if chemoprophylaxis is successful, will it then increase unsafe sexual behavior by individuals who no longer fear they will develop AIDS, possibly resulting in increased transmission rates? Psychologists are continuing their study in this area.

Policy implications
The counseling, testing and postexposure-prevention studies are examples of the new AIDS Research Institute?s multidisciplinary approach, combining clinical, policy and behavioral research, Coates says.

?By looking at all aspects of the problem simultaneously, we get tremendous power to understand all its dimensions and to apply solutions more readily,? he says.

Influencing policy is the area in which more psychologists need to become involved, says Coates. An example of behavioral research influencing policy is in Mexico, says psychologist Susan Pick, PhD, director of the Mexican Family Institute for Research on Family and Population, an independent nongovernmental organization. The institute has conducted opinion surveys that showed strong public support for AIDS-prevention programs that include sex education in the schools. By publicizing the survey results, Pick says, the institute helped pressure the national government to launch a national sex-education program.

To promote condom use, the institute trained Mexican pharmacists to ?act as friends, as advisers? in telling customers about AIDS prevention and how to use a condom. The programs also targeted adolescents, training them to teach other teen-agers about AIDS prevention.

Pick acknowledges that effect AIDS-prevention programs still face many obstacles in Mexico, among them the government?s continuing refusal to speak frankly about homosexuality and bisexuality and to target prevention at these groups.

?You have to address all the different influences?the community, the mass media, the schools, the parents,? Pick says. ?You have to have everyone involved. And you need the political will to give it a big fight, which is now happening.?

Peter Freiberg is a writer in Miami Beach, Fla.