Fall 18

AIDS still kills, in very large numbers. But the right blend of science and policy could help end the scourge. Also in this issue, antibiotic resistance, blunting the effectiveness of one of medicine’s most important tools, is rising just as the search for new infection-fighting drugs falters. These new approaches may help. And how preparing for a future voyage to Mars could unlock secrets of the human body that might be put to use here and now.