The AIDS Epidemic That Wasn’t : CRISIS Heterosexual Behavior in the Age of AIDS<i> by William H. Masters, Virginia E. Johnson and Robert C. Kolodny (Grove Press: $15.95; 243 pp.) </i>

How much of a threat is AIDS to heterosexuals? Until a year ago, public health officials argued that while the number of cases of heterosexual AIDS was very small, heterosexuals represented the fastest-growing segment of the epidemic and that the number of cases among them would soon begin to rise steeply, following the pattern that homosexuals had experienced a few years before.

But the number of people who contracted AIDS from straight sex did not continue rising--much less accelerate--and the public-health Establishment had to revise its predictions. AIDS is no longer considered the threat to American heterosexuals that it once was. There is no doubt that the virus that causes AIDS does not discriminate. In Africa, AIDS is pandemic among heterosexuals. But, the argument now goes, those who think that AIDS will spread rapidly among the straight population in this country have to explain why that hasn’t happened yet.

Now come William Masters and Virginia Johnson, the veteran sex researchers, along with a co-author, Robert Kolodny, to tell us that public-health officials had it right in the first place. “The epidemic has clearly broken out into the broader population and is continuing, even now, to make its silent inroads of infection while many maintain an attitude of complacency, not realizing that they too are at risk,” they write in their highly charged, somewhat thin, new book.

To the question of why, if they are right, there aren’t more cases of straights with AIDS, Masters, Johnson and Kolodny reply: Because it takes a long time for a person to come down with the disease after having been infected with the virus. But the incubation period is no shorter for gays than for straights: Why are so many more gays infected?

What is most remarkable about their book is how little it contains that is new. Aside from one chapter that reports the findings of their survey of heterosexuals in four parts of the country--about which more in a moment--most of the book is a repetition of recently discredited public-health predictions and advice.

Even their claims that AIDS can be spread in ways other than sexual contact or by drug addicts sharing needles are not new. But the scenario they outline is so far-fetched that it should reassure readers rather than frighten them. In a chapter entitled, “Can You Catch AIDS From a Toilet Seat?” this is what they say:

“If infected blood (from a cut, scrape, ulcer, blister or rash on the buttocks) or infected semen (either dripped from the penis or spilled from a condom) is inadvertently left on a toilet seat and someone who comes in contact with this material also happens to have a break in the skin at the point of contact, the virus may enter the body and infection may occur.”

It is also possible to be hit by a cement mixer while crossing the street. Do Masters, Johnson and Kolodny urge people not to cross the street?

Whatever the theoretical possibilities about contracting AIDS from toilet seats, doorknobs, kissing or mosquito bites, there is a very simple demonstration that, in reality, AIDS is not transmitted this way. If it were, or if AIDS could be transmitted through the air, like the flu, or by an infected person sneezing on you, there would be no high-risk groups. We would all be equally at risk.

The fact that AIDS is overwhelmingly centered among homosexuals and IV drug users tells us how it is transmitted. The infection pattern is not like the flu.

Masters and Johnson have been controversial figures in sex research since their best seller, “Human Sexual Response,” was published in 1966. In the years since that book, the quality of their research techniques, definitions and conclusions has sometimes been criticized, particularly after they began offering short-term, intensive (and expensive) therapy at their institute in St. Louis for people with sexual dysfunctions. Other researchers have called into question the rates of success that Masters and Johnson claim in their therapy.

Masters and Johnson were also criticized in 1979 when they published “Homosexuality in Perspective,” the results of 10 years of research from 1968 through 1977, in which they claimed that they had been able to “convert” homosexuals into heterosexuals by using their intensive therapy techniques.

The authors’ history in these areas is very much to the point in assessing the current book. To support their finding that the AIDS virus--if not AIDS itself--is running rampant through the population at large, they report on their study of 800 heterosexuals, 400 of whom had been strictly monogamous for five years and 400 of whom had had at least six different sex partners a year during that time.

“Among the 400 strictly monogamous men and women in our sample, only one man tested positive for antibodies to the AIDS virus,” they found. “There was a strikingly higher prevalence of infection in the study group: 10 out of 200 men (5%) and 14 out of 200 women (7%) tested positive for HIV antibodies. . . .

“Since the hypothesis underlying our investigation was that heterosexuals with the largest number of sexual partners would be most likely to be infected with the AIDS virus, we also examined the study subgroup that averaged more than 12 sex partners annually for the preceding five years. Not surprisingly, the prevalence of infection was even higher in this group: 14% (11 out of 80) of the women and 12% (7 out of 59) of the men in this category” carried AIDS antibodies.

They concede that the subjects in their study were not selected randomly and may not be representative of the American public at large, but they conclude nonetheless that “the AIDS virus has certainly established a beachhead in the ranks of heterosexuals, and because heterosexuals who have large numbers of sex partners are most likely to be infected, the odds are that the rate of spread among heterosexuals will now begin to escalate at a frightening pace.”

This is precisely what public-health officials were saying two years ago and precisely what has not happened.

Masters, Johnson and Kolodny based their findings of 6% AIDS infection on a survey of 400 people. But the American Red Cross has tested blood from 8.8 million blood donors a year and found an infection rate of about .2%, 30 times lower than the new findings. The Defense Department has tested 4 million military personnel and found an infection rate of about .15%, which is lower yet. The findings based on these much larger population samples are more believable than those in this book.

In short, Masters, Johnson and Kolodny have performed no public service by publishing their study, a study that, by the way, they did not subject to outside review, the well-established and time-honored way to guarantee the accuracy and reliability of new research. Whatever their motives, their book has simply added to the public cacophony and confusion on this disturbing subject.