The drugs are not simple to administer. For one thing, they’re given by intravenous infusion, so patients must go to health centers where this can be done. But since they’re likely contagious, existing IV facilities, like where patients receive chemotherapy, can’t be used. Another issue is that the drugs need to be given early in the course of the disease. The FDA’s guidance for health-care providers says they should be administered as soon as possible after diagnosis, and within 10 days of symptom onset. It recommends against use of the drugs once patients are so sick they’re hospitalized. But many patients don’t feel sick right away, so the idea of an IV-infused drug doesn’t occur to them immediately after diagnosis, Slaoui and Azar suggested.