Prospective study of respiratory infections at the U.S. Naval Academy

Midshipmen at the U.S. Naval Academy have recently suffered epidemics of upper respiratory tract infections. Seeking to determine cause, in June 1998 we enrolled 1,243 (99.5%) of 1,249 new midshipmen (plebes) and followed them during their first 11 months of training. Eighty-five plebes sought medical attention for acute respiratory disease. Using culture, serologic studies, and polymerase chain reaction, considerable evidence for respiratory pathogen infection was found among the ill subjects: Chlamydia pneumoniae in 41 (52.6%), Mycoplasma pneumoniae in 19 (25.3%), influenza in 11 (14.2%), Streptococcus pneumoniae in 6 (7.3%), and adenovirus in 1 (1.2%). Additionally, 873 (81%) the 1,077 plebes who completed an end-of-year questionnaire complained of having one or more respiratory symptoms (>12 hours) during their first year of school. Of these, 132 (15%) reported that the symptoms significantly affected their performance. Study results suggest that respiratory infections were frequent, had a significant adverse impact on training, and were often attributable to bacterial pathogens.