MEDICINE

Breakthrough against a modern plague

Pat Ohlendorf February 4 1985
MEDICINE

Breakthrough against a modern plague

Pat Ohlendorf February 4 1985

Breakthrough against a modern plague

MEDICINE

Pat Ohlendorf

Because the mysterious and invariably fatal disease began spreading among homosexuals four

years ago, it soon became known as the “Gay Plague.” Now, with Acquired Immune Deficiency Syndrome (AIDS) infecting and—inevitably—killing small but growing numbers of heterosexual men, women and even children, it is

beginning to seem more like a modernday version of the Black Death. However, the awesome scope of the AIDS threat has stimulated worldwide research and last week two research groups in Washington and Paris announced that the disease may eventually be controllable. The reason: by cracking the genetic code of the recently discovered AIDS virus, the scientists hope that the development could lead to an effective treatment, a vaccine and a cure.

Still, although the disease is not claiming large numbers of victims, AIDS has indeed become an epidemic, AIDS cases have been rising dramatically every year since 1981 according to Peter Drotman, a medical epidemiologist at the U.S. Centers for Disease Control in Atlanta. By last week 7,891 adults in the United States had contracted AIDS, 73 per cent of them homosexual or bisexual men. In Canada, where the disease struck later, 174 adults (121 of them homosexual or bisexual men) have

caught the fatal disease. So far, AIDS has killed 3,758 Americans and 93 Canadians.

The disease is particularly frightening because no one diagnosed as having AIDS has yet recovered. In fact, no AIDS patient has survived longer than three years after diagnosis. Most die of a oncerare skin cancer called “Kaposi’s sarcoma” or a particularly deadly type of pneumonia. And some experts estimate

that the incidence of AIDS-related complex (ARC), caused by the same virus, is much greater than the incidence of AIDS. And no one yet knows if ARC represents a mild form of the disease from which patients can recover or if it is merely a prelude to AIDS, which at present as many as 15 per cent of North American ARC patients have developed.

Apart from the relatively few cases of AIDS caused by transfusions of contaminated blood, most scientists believe that sexual promiscuity accounts for the rising number of AIDS cases among heterosexuals. Semen and blood are the primary body fluids that carry the virus. But because the transmission of AIDS is relatively slow and its symptoms do not develop for one to as many as five years after infection, experts, including Gordon Jessamine, chief of the field epidemiology division at the federal Laboratory Centre for Disease Control in Ottawa, say that AIDS will not spread quickly through the general population.

Declared Jessamine: “We are going to see more cases of AIDS in Canada in 1985 than in 1984. But they will belong to the same groups that we know have a high risk, because those people were infected over the past one to two years.”

Last week’s announcements of the genetic mapping, or “sequencing,” of the AIDS virus—discovered by French researchers only last spring—is a major advance. And fierce competition be-

tween two prominent research groups in France and the United States probably hastened this latest development. The French researchers are led by Dr. Luc Montagnier at the Pasteur Institute in Paris, and the Americans are led by Dr. Robert Gallo at the U.S. National Institutes of Health (NIH) in Bethesda, Md.

The French discovered the AIDS virus but the American press ignored the discovery, concentrating instead on a similar finding by the NIH team several months later. Montagnier maintains that the NIH team merely “confirmed and reproduced our work.” But Gallo contends that the French research would have been meaningless without critical information from the Americans. Declared Montagnier: “The greatest sin for scientists is dogmatism. I am not reproaching anyone. I note simply that our competitors were slowed down by holding onto a false idea.”

More important than the dispute between the scientists is the possibility

that the discovery will lead to an AIDS vaccine. But such researchers as Montagnier say that a vaccine could not be ready for at least two to five years and others caution against false optimism: only one other experimental vaccine—used to treat leukemia in cats —has been developed to fight a virus similar to the one that causes AIDS.

Some researchers also express concern that the AIDS virus may be mutating, which would make it more difficult to create a new vaccine. Still, Montagnier says he is optimistic that the AIDS virus is fairly stable. Said Montagnier: “Unlike the influenza virus, the variations in the AlDS-producing virus do not seem to indicate any broad ability to

create rapid mutations.”

A vaccine would protect only those who have not contracted the AIDS virus. But for AIDS and ARC victims alike, the new discovery offers the possibility of an effective treatment and even a cure. So far, scientists have tried many remedies, from chemotherapy and radiation to interferon, antiviral drugs and even bone marrow and thymus cell transplants.

But because they do not destroy the virus itself the best of them produce only brief remissions.

Now, knowing the structure of the virus’s genetic code, scientists can begin attacking its vulnerable points. Explained Montreal clinician Roger LeBlanc, a private practitioner specializing in

infectious diseases: “It is like a building. If you want to blow it up, you have to know how it is put together and know where the weak points are.”

Another potential offshoot of the recent work is the development of a more accurate diagnostic test for AIDS. The current test, which indicates the presence of the disease through detection of antibodies to the AIDS virus in the blood, cannot confirm the presence of the virus itself. Surveys of male homosexuals in major Canadian cities last year have shown that as many as 30 per cent of them harbor the antibodies. But doctors do not know whether a positive result means a patient will eventually die, whether he can transmit the disease or, indeed, whether he has become immune to it. But they do know that living with the knowledge of that uncertainty can be devastating.

At the same time as AIDS research is progressing rapidly, recent statistics are discrediting the first impression

that the disease is a “Gay Plague.” Declared Flossie Wong-Staal, head of the molecular genetic section of Gallo’s lab: “There is nothing magic about homosexuality. Intimate contact is the root of transmission, not sexual preference.” Still, researchers cannot fully explain why the disease is so much more prevalent among homosexuals, but some suggest that greater promiscuity among homosexuals than heterosexuals is the likely cause. Montagnier, for one, said that one theory is that sperm introduced anally could depress the body’s immune system, making it more vulnerable to attack by the AIDS virus. Those who dispute the theory argue that it ignores the lack of a high incidence of AIDS

among women. And in Central Africa, where the incidence of AIDS is the highest in the world, women and men develop the disease in equal numbers.

Physicians approach AIDS with a mixture of fear and optimism. Admitted clinician LeBlanc, who has lost eight patients to AIDS: “I am feeling jittery—I’m almost scared now when I see a patient with an infection.” But, he added, “I believe that those ‘hot’ research labs that are rightly receiving so much attention will give us the answers. In treatment today, we are doing everything we can to help our patients hang on a while longer—as long as we possibly can—so they will still be here when those answers come.” A year ago that optimism would have seemed unfounded. But with the recent advances against a terrifying modern epidemic, hope has become almost as infectious as the disease itself.

Ronald Koven