【案例分析题】

New Attempts to Eradicate AIDS Virus
A high-profile attempt to eradicate the AIDS virus in a few patients continues to show promise.
But researchers won’t know for a year or more whether it will work，scientist David Ho told journalists this Wednesday for the Fourth Conference in Viruses and Infections.
’This is a study that’s in progress，’says Ho，head of the Aaron Diamond AIDS Research Center，New York.
The study involves 20people who started combinations of anti-HIV drugs very early in the course of the disease，within 90days of their infections.They’ve been treated for up to 18months.Four others have dropped out because of side effects or problems complying with the exacting drug system.
The drugs have knocked the AIDS virus down to undetectable levels in the blood of all remaining patients.And，in the latest development，scientists have now tested lymph nodes and semen from a few patients and found no virus reproducing there，Ho says.’Bear in mind that undetectable does not equal absent，’Ho says.
Ho has calculated that the drugs should be able to wipe out remaining viruses--at least from known reservoirs throughout the body--in two to three years.But the only way to prove eradication would be to stop the drugs and see if the virus comes back.On Wednesday，Ho said he wouldn’t ask any patient to consider that step before 2years of treatment.
And he emphasized that he is not urging widespread adoption of such early，aggressive treatment outside of trials.No one knows the long-term risks.
But other scientists are looking at similar experiments.A federally funded study will put 300patients on triple-drug treatments and then see if some responding well after six months can continue to suppress the virus on just one or two drugs，says researcher Douglas Richman of the University of California，San Diego.Some patients in that study ’also may be offered the chance to stop therapy after 18months or more，he says.

According to the passage, the attempt to eradicate the AIDS virus（）