Dr. David Ho doesn't look like a gambler. With his boyish face and slender build, he could more easily pass for a teenager than for a 44-year-old father of three--or, for that matter, for a world-renowned scientist. In fact, when he was an undergraduate at the California Institute of Technology back in the 1970s, Ho hung around the blackjack tables in Las Vegas, tilting the odds in his favor by memorizing each card as it was played. He got so good at counting cards that he was thrown out of several casinos.
Today Ho is still something of a gambler, though in a very different field and for much bigger stakes. The director of the Aaron Diamond AIDS Research Center in New York City, he has come up with a daring strategy for flushing out the virus that causes AIDS. As he explained at the 11th International Conference on AIDS in Vancouver, Canada, last summer, Ho (like more and more doctors) is using powerful new drugs called protease inhibitors in combination with standard antiviral medications. But unlike most doctors, he gives the so-called combination therapy to patients in the first few weeks of infection.
Already the HIV in his patients' blood has dropped so low it can no longer be measured. Because he is attacking early and not waiting for full-fledged AIDS to develop, Ho told the conference, there is a good chance that within two or three years the virus could be completely eliminated.
Eliminated. Just a few months ago, no one in the AIDS community and no reputable scientist would presume to imagine such a thing. Journalists, activists and researchers peppered Ho with questions at the podium. Had he found the cure? Could people stop worrying about AIDS? Could they throw away their condoms?
No, no and no. What he had done, Ho explained, was begin an experiment that might, under the right circumstances, eliminate the virus from a small group of men caught within three months of infection. He couldn't offer the same hope to the estimated 100,000 patients in later stages of infection who in the past year have begun taking the same antiviral "cocktails"--often with encouraging results--but whose AIDS is probably too far advanced for them to expect a long-term recovery.
Like so many promising HIV treatments, Ho's strategy could fail. It could even backfire if it is mistakenly touted as a kind of "morning after" treatment that allows people to relax their guard and engage in risky sexual behavior. By desensitizing the virus to medications, it could jeopardize a patient's ability to respond to future treatments. Worse yet, it could inadvertently create a mutant strain of virus resistant to all currently available drugs--a kind of super HIV--that could lead to a second, even more devastating AIDS epidemic.
There are other problems. Even if the treatment works, it isn't practical. HIV-positive patients would have to start taking the drugs immediately after infection, before they realize they're sick. And even if the drug cocktails can be made to work in the later stages of infection, they are far too expensive to do much good for the 20 million people in the developing world who are infected with HIV. In the long run, scientists believe, only an AIDS vaccine will stop the global epidemic.