Dennis Drenner / For The Times
Dr. Kyle Petersen, an infectious disease specialist with the U.S. Navy, examines a colony of Acinetobacter baumannii at the National Naval Medical Center. Petersen was one of the first in 2003 to sound the alarm on an outbreak involving this unusual bacterium that was making the rounds among troops wounded in Iraq or Afghanistan. Years later, hundreds of patients in American military hospitals have become infected.
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