Doxycycline Prophylaxis for Skin and Soft Tissue Infections in Naval Special Warfare Trainees, United States

In 2015, several severe cases of skin and soft tissue infection (SSTI) among US Naval Special Warfare trainees prompted the introduction of doxycycline prophylaxis during the highest-risk portion of training, Hell Week. We performed a retrospective analysis of the effect of this intervention on SSTI incidence and resulting hospital admissions during 2013-2020. In total, 3,371 trainees underwent Hell Week training during the study period; 284 SSTIs were diagnosed overall, 29 of which led to hospitalization. After doxycycline prophylaxis was introduced, admission rates for SSTI decreased from 1.37 to 0.64 admissions/100 trainees (p = 0.036). Overall SSTI rates remained stable at 7.42 to 8.86 SSTIs/100 trainees (p = 0.185). Hospitalization rates per diagnosed SSTI decreased from 18.4% to 7.2% (p = 0.009). Average length of hospitalization decreased from 9.01 days to 4.33 days (p = 0.034). Doxycycline prophylaxis was associated with decreased frequency and severity of hospitalization for SSTIs among this population.