He had been put on a powerful regimen of antibiotics by doctors aboard the hospital ship Comfort in the Persian Gulf. But something was wrong.

He was in shock and bleeding from small pricks where nurses had placed intravenous lines. Red, swollen tissue from an active bacterial infection was expanding around his abdominal wound. His immune system was in overdrive.

How odd, thought Dr. Kyle Petersen, an infectious disease specialist. He knew of one injured Iraqi man with similar symptoms and a few days later encountered an Iraqi teenager with gunshot wounds in the same condition.

Within a few days, blood tests confirmed that the medic and the two wounded Iraqis were infected with an unusual bacterium, Acinetobacter baumannii.

This particular strain had a deadly twist. It was resistant to a dozen antibiotics. The medic su