First came the media wave of fear and scenarios of Armageddon, as though AIDS were the Space Age cousin of Black Death, which ravaged Europe in the 14th century.

Now, the anti-hype backlash has started, and it's trendy in the press to minimize the AIDS epidemic.

Columnist Michael Kinsley of New Republic magazine, writing in this newspaper, tells us that "a year from now, no one will be talking much about AIDS anymore." Pulitzer prize-winning columnist Charles Krauthammer is convinced, "AIDS is not the pandemic its publicists would like us to believe."

In the fickle fashion of medical news, it would seem that AIDS is destined to become just another "disease of the week," following in the wake of previous high-profile health "crises" such as drug abuse, herpes and nuclear winter.

But if press coverage has changed in the last month, the reality of AIDS has not. ::

"People shouldn't lose sight of the fact that the prediction of a quarter of a million cases in the United States is coming true," says Nobel prize winner David Baltimore, director of the Whitehead Institute in Cambridge, Mass., and cochairman of the National Academy of Sciences report on AIDS. "We have a major problem, and no amount of wishing is going to make it go away."

More than 110 countries around the world have reported cases. In the AIDS-belt countries of Africa, the World Health Organization estimates that 25 to 30 percent of all hospital beds are filled with men and women who have AIDS. In New York City, AIDS is the leading cause of death in men ages 25 to 44 and in women 25 to 34.

The "no problem" contingent notes that Americans are much likelier to die of something else: Heart attacks claim 540,000 lives a year; cancer, 483,000. One million Americans suffer from Alzheimer's disease. Why should there be all this fuss -- and resources -- devoted to AIDS?

There are several reasons why AIDS deserves what Krauthammer too archly calls "its privileged position" in the realm of diseases.

It's new. Unlike cancer, drug abuse or other high-profile medical problems, AIDS is an entirely new disease. The first case was reported in 1981. The earliest evidence of the AIDS virus has been traced to a 1959 blood sample taken from a tuberculosis patient in Africa.

It's virtually 100 percent fatal. This is typical of the early stages of any new infectious epidemic. In contrast, there are effective therapies for heart disease and certain forms of cancer, and significant numbers of patients live for many years after the diagnosis. In terms of terribleness, AIDS might more aptly be compared to the incurable genetic disorder of Huntington's disease, which also hits people in middle age and destroys the mind and body. The difference is that Huntington's disease is not infectious and remains relatively rare. AIDS has already jumped from 183 cases in the U.S. in 1981 to nearly 40,000 cases today and is expected to reach 270,000 over the next four years.

AIDS is political. Last week, President Reagan made his first visit to AIDS patients -- children being treated at the clinical center at the National Institutes of Health. The president likened AIDS to smallpox and polio, and introduced members of his new AIDS advisory panel.

Throughout the world, AIDS has become highly politicized, raising concerns that AIDS angst might unleash a wave of discrimination and even violence against patients and high-risk groups. "AIDS has unveiled thinly disguised prejudice about race, religion, social class and nationality," says WHO's Dr. Jonathan Mann. ::

Overshadowing all this is scientific uncertainty. Despite advances in isolating the virus and developing experimental drugs, AIDS experts do not have answers to the big questions: How did AIDS start? How fast is it spreading? (Actual cases reflect the spread of the virus five years ago -- not the extent of infection today.) How bad is the epidemic going to get?

It is this uncertainty about AIDS that causes the pendulum to swing back and forth in the public's perception of the disease.

"People want simple straightforward answers," says Dr. Harold Jaffe, chief AIDS epidemiologist at the Centers for Disease Control in Atlanta. "Is the housewife in Cedar Rapids at risk? If no, we don't want to hear about it. If yes, then let's go all out and do extreme measures like quarantine. The problem of AIDS is more complex than that," he says.

A key issue in the U.S. right now is whether AIDS is going to "break out" into the so-called "mainstream" heterosexual community. Scientists know that the virus can be transmitted through heterosexual intercourse. In Africa and Haiti, the disease affects both men and women -- yet in the U.S. and Europe, AIDS is primarily a disease that strikes homosexuals and drug abusers. Why is this?

"I don't think we really know," says Jaffe.

There are a number of theories: different sexual life styles in parts of Africa; higher rates of venereal diseases there, such as genital ulcers thought to increase the risk of contracting infection; lack of screening blood for contamination; more frequent use of transfusions and sharing of unsterilized needles in medical practice, as well as the burden of malnutrition and other diseases that weaken the immune system.

CDC officials say that at the moment the risk of heterosexual spread is confined to intravenous drug abusers and their sex partners and the sex partners of bisexual men. These scientists believe that there will not be the explosive increase among other heterosexuals that has been seen among gays and drug abusers.

Yet some say it is only a matter of time. Even if AIDS in the U.S. never becomes as widespread as it is in Africa, many researchers predict a slow and steady increase among heterosexuals so that in 10 or 15 years, a sizable proportion of the general population will be affected. "At that time, people will start to panic," says Dr. Myron Essex of Harvard's School of Public Health. ::

Just as uncertain as the heterosexual spread question -- and as politically touchy -- is the question of how and where AIDS began. One theory is that the virus changed from a harmless agent into a killer. Viruses are known to mutate -- the constantly changing flu virus is one example. Another theory is that the AIDS virus "jumped" from animals to human beings. A similar virus has been found in monkeys, but does not cause disease in infected animals. One hypothesis is that the method of catching and trapping monkeys in Africa causes so much bleeding in the animals and the trappers that the virus could be passed along in blood.

But any scientific speculation on the origins of AIDS quickly translates into political tension. African nations are very sensitive about being blamed for starting AIDS. After Dr. Robert Gallo of the National Cancer Institute announced at the Third International Conference on AIDS in June that he had isolated yet another AIDS virus from Nigerian patients, that country protested the report. In Africa, meanwhile, people were led to believe that the disease came from American military advisers sent to Africa -- or was a plot of chemical warfare.

The medical and political confusion over AIDS is reminiscent of the first syphilis outbreak in the late 14th and early 15th centuries. "Fantastic theories" at the time, according to Hans Zinsser, author of "Rats, Lice and History," said the epidemic "was started by the intercourse of a man with a mare . . . {or} a similar relationship with a monkey." The French called syphilis the "Neapolitan disease"; the Italians named it the "French affliction." To this day, scientists haven't been able to figure out if the New World Indians gave it to the Europeans or the other way around.

It is likely that many of the questions about AIDS will remain unanswered as the disease continues to spread. In this environment of uncertainty, public policy must be made: How, for example, will hospitals handle the increased load of cases? Who will pay -- the government? Private insurance?

This same uncertainty also fuels the current chic to play down AIDS in the media. In the absence of new information, the public is tired of hearing about AIDS. The concern is that this genre of denial may mask a more disturbing political trend -- that of ignoring AIDS because it doesn't seem to pose a threat to white middle-class heterosexuals who make up the majority of voters.

But AIDS is not a disease that will respond to benign neglect. As NCI's Gallo puts it: "Until we have a vaccine, this virus is not going to go away. It's going to be here forever."