There are also disadvantages. Just because a drug is effective against one disease does not mean it would work against Ebola. It is possible that some drugs might actually harm Ebola patients by making their infection worse or by causing severe side effects. One expert warns that the Ebola infection progresses rapidly within the body and that a drug that helps on Day 2 might become harmful by Day 7. That is why even approved drugs should be administered in clinical trials to determine whether they work against Ebola. Though it would not be easy to conduct such trials, several experts have said they think it could and should be done.

The idea of using approved drugs was proposed in an Op-Ed article in The Times on Aug. 16. Thirty respected clinical investigators and epidemiologists around the world are on record as supporting the article. Other experts have expressed reservations and have called for drug tests in nonhuman primates first. Even those who have backed the use of existing drugs because “desperate situations justify desperate measures” have stressed that there needs to be some evidence a drug might work.

Beyond this, the primary need right now is supportive care — like keeping patients hydrated, which allows many to recover even without a drug treatment. This requires that hospitals and clinics have isolation units for the patients and protective gear for doctors and nurses to prevent the spread of the virus. Once such facilities exist, it should be possible to compare one group of patients given standard supportive care with another group given supportive care plus a drug that might help them.

The World Health Organization is scheduled to hold a meeting in Geneva next week with more than 100 experts, including 20 from West Africa, to discuss potential therapies and vaccines for the Ebola virus and explore ways to expedite clinical trials and ramp up production of the most promising treatments. The meeting should be sure to consider the use of drugs that are already approved for other diseases and are readily available.