GENEVA. — The world-wide AIDS epidemic has taught us many things -- the importance of being ever alert to new viruses, the need for intense international cooperation in fighting diseases that respect no political boundaries -- and how little we know about the sexual and drug proclivities of both men and women.
Despite several years of explicit advertising to educate people about unprotected sex, there is still a marked reticence among political and civic leaders to probe too deeply into what really goes on in the bedroom. When she was prime minister, Margaret Thatcher scotched a proposal to mount a major study of British sexual behavior. And the U.S. Congress killed an attempt by the Center for Disease Control to undertake similar research in America.
We are extraordinarily ignorant of how, with whom and how often people have sex, knowing most of what we do by hearsay. Only one serious study of human sexual behavior exists, the famous Kinsey report, now over 40 years old. Its methodology would not pass muster with professional sociologists today, and its conclusions must be regarded as rough and ready.
The consequence of our ignorance is that our knowledge of sexual behavior is riddled with myths and half-truths. We certainly have norms and conventions in society, but how close or how far away average behavior is from these is, for the most part, guess work and wishful thinking.
It is assumed by some, for example, that masturbation and oral or anal sex are not what good people do. ''Aberrant'' sex is often equated in popular culture with people of other colors or ethnic groups.
Contrariwise, others, seeking to overturn our popular myths and conventions, suggest that we are not naturally monogamous -- that the natural state is serial monogamy, entering relationships that, while exclusive, only last five or ten years and then we go on to another. There is some evidence for this in the high divorce rate in the Western world, but it is difficult to prove with the facts available.
Eastern societies have their myths, too. In Japan, for example, society refuses to acknowledge that homosexuality is practiced. Yet we know it is, and quite extensively.
In many Arab countries, a question to the Ministry of Health about homosexuality will be met with the response it doesn't exist. The inquirer will be told that in Arabic there is not even a word for it. Yet the popular Western stereotype of Arab societies is that many Arab men wear their homosexuality as a badge of honor. Who is right?
In Eastern Europe in pre-glasnost days it was quite common for )) health officials, politicians and commentators to describe AIDS as a disease that existed only in capitalist societies. Only relatively recently have communist countries acknow- ledged that promiscuity, prostitution and drug use existed on any scale.
Perhaps the most taboo and unexplored subject of all is bisexuality, one who has sex with both men and women. One American authority, June Osbourne of the University of Michigan, argues that the number of bisexual men in the U.S. may be as many as the number of homosexuals. Some researchers argue that we see only the tip of an immense iceberg if we rely on what only a few will admit to, pointing to surveys of male prostitutes that suggest the majority of their clients are married men.
In Brazil anthropological studies of modern city society have found that the word ''homosexual'' is reserved for the passive partner in the male sex act. Active partners consider themselves heterosexual. This suggests that bisexuality in Brazil is much more prevalent than was thought.
Another unanswered question is the degree to which sexual behavior has changed through the ages. Art and literature would suggest not much. But we don't really know, and certainly it has gone through fads and phases. Clearly in our era the advent of the pill has loosened traditional constraints. The pill has generated its own theories, and perhaps myths, of heightened sexual awareness among women. But how sure can we be?
And how does age affect our sexual attitudes? Are the AIDS-dangerous practices essentially limited to young people still experimenting with sex? Do most mature adults push these kinds of thoughts and practices aside and settle for fairly conventional sexual activity?
All this lack of knowledge and bits and pieces of knowledge leave our health and education authorities ignorant, exposed and ineffective in the campaign against AIDS. If we want to wage an effective battle we need to know what the target is; we need to know exactly what's going on among whom. Propaganda that goes out to everyone is not a focused instrument of persuasion. It is not the way advertisers sell cars and it should not be the way we educate people to avoid the risk of AIDS.
The World Health Organization, in a first attempt to deal with this dearth of knowledge, has devised a survey on sexual behavior that can easily be adapted to any culture, and that can use a country's own researchers. More than 40 countries have decided to initiate this survey. When it's completed we should be able to start building a picture of how human life actually functions on this most intimate of levels.
The first preliminary reports from 16 countries will be made available at the 7th International Conference on AIDS, meeting next week in Florence, Italy. At last substance can begin to replace myth in the long struggle against AIDS.
Jonathan Power writes a column on the Third World.