EPIDEMIC WITHOUT A SILVER BULLET

"In the period October 1980-May 1981, 5 young men, all active
homosexuals, were treated for biopsy-confirmed Pneumocystis carinii
pneumonia at 3 different hospitals in Los Angeles, California. Two of
the patients died."

- -- Centers for Disease Control, June 5, 1981

WASHINGTON -- Those words 25 years ago announced the arrival of
something most Americans thought anachronistic -- an infectious
disease epidemic. At first it was called GRID -- gay-related immune
deficiency. In September 1982, CDC renamed it acquired immune
deficiency syndrome -- AIDS.

Its worldwide toll has already exceeded the 20 million killed by the
14th-century bubonic plague. By 2020, it probably will have killed
more than has any epidemic in history, with most fatalities in
sub-Saharan Africa, where it probably began about 75 years ago after
some people who ate wild chimpanzees in Cameroon became infected with
a low-virulence progenitor of the virus that causes AIDS.

An epidemic requires both a microbe and an enabling social context.
In Africa, aspects of modernity in a primitive setting became a
deadly combination: HIV was spread by roadside prostitutes serving
truckers and soldiers traveling on modern roads. Africa's wars caused
population dislocations; economic development caused migrations of
workers across porous borders. Both weakened families and dissolved
traditional sexual norms. Jet aircraft integrated Africa into the
world flow of commerce and tourism. In 1980s America, the enabling
context included a gay community feeling more assertive and
emancipated, and IV drug users sharing needles.

AIDS arrived in America in the wake of the Salk vaccine which, by
swiftly defeating polio, gave Americans a misleading paradigm of how
progress is made in public health. Pharmacology often is a small
contributor. By the time the first anti-tuberculosis drugs became
available in the 1950s, the annual death rate from TB had plummeted
to 20 per 100,000 Americans, from 200 per 100,000 in 1900. Drugs may
have accounted for just 3 percent of the reduction. The other 97
percent was the result of better nutrition and less urban crowding.
Thanks to chlorination of water and better sanitation and personal
hygiene, typhoid, too, became rare before effective drugs were available.

Which suggests that the most powerful public health program is
economic growth. And the second-most powerful is information.

The 14th-century Black Death killed one-third of Europe's population,
but it was in the air, food and water, so breathing, eating and
drinking were risky behaviors. AIDS is much more difficult to
acquire. Like other large components of America's health care costs
(e.g., violence, vehicular accidents, coronary artery disease, lung
cancer), AIDS is mostly the result of behavior that is by now widely
known to be risky.

The U.S. epidemic, which so far has killed 530,000, could have been
greatly contained by intense campaigns to modify sexual and drug-use
behavior in 25 to 30 neighborhoods from New York and Miami to San
Francisco. But early in the American epidemic, political values
impeded public health requirements. Unhelpful messages were sent by
slogans designed to democratize the disease -- "AIDS does not
discriminate" and "AIDS is an equal opportunity disease."

By 1987, when President Ronald Reagan gave his first speech on the
subject, 20,798 Americans had died, and his speech, not surprisingly,
did not mention any connection to the gay community. No president
considers it part of his job description to tell the country that the
human rectum, with its delicate and absorptive lining, makes
anal-receptive sexual intercourse dangerous when HIV is prevalent.

Twenty years ago a San Francisco public health official explained
death's teaching power: Watching a friend die, like seeing a wreck
along a highway, is sobering. But after driving more slowly for a few
miles, we again speed up. AIDS has a more lasting deterrent effect.

There has, however, been an increase in unsafe sex because
pharmacological progress has complicated the campaign against this
behavior-driven epidemic. Life-extending cocktails of antiviral drugs
now lead some at-risk people to regard HIV infection as a manageable
chronic disease, and hence to engage in risky behavior. Furthermore,
the decline of AIDS mortality means that more persons are surviving
with HIV infection -- persons who can spread the virus. And drugs
like Viagra mean that more older men are sexually active.

Still, even with no pharmacological silver bullet, AIDS deaths in
America have been declining for a decade. In Africa, where
heterosexual sex is the primary means of transmission, the death rate
is steady relative to population growth, and the age of beginning
sexual activity is rising, as is the use of condoms. Human beings do
learn. But they often do at a lethally slow pace.

George F. Will's column is distributed by the Washington Post Writers Group.