WE MUST ACT NOW TO STOP AIDS EPIDEMIC NUMBER OF INFECTIONS WORLDWIDE COULD TOP 150 MILLION IN 20 YEARS.

Byline: Michael S. Gottlieb

I remember standing on a beach on an overcast day in 1985, feeling as if I knew a tragic accident was about to happen and no one could hear my warnings.

Now the world knows about what I feared then - the enormous size of the AIDS epidemic - but to look ahead from here is to feel again that not enough people appreciate how a failure to act effectively now would undermine the quality of life for everyone on the planet.

In the 20 years ahead, AIDS can be brought under much better control in the United States - if we don't let down our guard - but it will be devastating in some other parts of the world.

The annual incidence of new cases of HIV could decline in this country from an estimated 40,000 a year to a few thousand by 2010. Future generations of antiviral drugs will reduce the virus further in body fluids.

For those already infected, new drugs can be expected to push HIV into a deep state of dormancy, though not to eradicate the virus. But to keep AIDS from continuing to spread, we need more culturally focused prevention programs, HIV education in the schools must be routine, and we must treat drug addiction as a medical problem, so that drug users stop spreading the disease.

Drug companies and government researchers are working now to develop vaccines. Promising candidates should be in use within 15 years, but will require continuous modification to keep pace with the virus' prodigious mutation rate and recombination of strains.

In the United States, the vaccines will probably be made available on a voluntary basis to gay men, intravenous drug users, heterosexual sexual partners of HIV-positive men and women, the incarcerated, and people traveling to high incidence regions.

But in Africa, the Far East and the former Soviet Union, HIV is now spreading virtually unchecked, and there is every indication that it will continue to do so for the next several years. According to United Nations statistics, the number of people who will have been infected worldwide by 2021 will easily top 150 million.

The U.S. Census Bureau has projected that in several African nations, deaths from AIDS will peak between 2010 and 2020. In Nigeria, 1.25 million are likely to die in 2020, at the peak of its epidemic, and by 2050 its population will be 73 million below pre-AIDS forecasts. In Southeast Asia, deaths in several countries are predicted to peak between 2015 and 2025. The Russian Ministry of Health recently predicted that 12 percent of the population of Russia will be infected by 2015.

By 2020, HIV will have caused more deaths than any disease outbreak in history. The constant experience of suffering and death, and the privation that results as economies fail in AIDS-ravaged countries, especially in Africa, could lead to the downfall of governments and the breakdown of law and order.

The United States, the European Union, Japan, the United Nations, the World Health Organization and prominent American foundations have an opportunity to mount a coordinated effort at damage control.

It is estimated that $10 billion annually is needed to develop health systems to deliver basic medical care and antiviral medications in Africa. In my opinion the effective deployment of these medications could reduce the mortality rate by at least 50 percent from what current estimates would predict, and completely eliminate transmission of HIV from mothers to their babies.

Action by relief agencies will be needed to tend to the dying, and to assist the millions of healthy children orphaned by AIDS. The United States could foster stability by forgiving debt owed by African nations hard hit by AIDS.

By the year 2010, I believe, several of the most promising HIV vaccine candidates could be under study in controlled clinical trials in countries with the highest rates of new HIV infection. And by 2021, one or more of these could have reached a level of effectiveness and safety that would allow its administration to children and adults in regions where the infection is most common.

We in the developed countries are finally beginning to grasp the size, scope, complexity and seriousness of the global HIV pandemic. It took AIDS to teach us what Nobel laureate Joshua Lederberg meant when he said: ``The world is just one village. Our tolerance of disease in any place is at our own peril.''

If we provide the money for effective action now, when the costs are still relatively low, we can minimize the setbacks that AIDS will cause at home and abroad. If we stand by or make token gestures, we will allow AIDS to spiral even further out of control.