Outbreak of respiratory illness associated with human adenovirus type 7 among persons attending Officer Candidates School, Quantico, Virginia, 2017.

A respiratory outbreak associated with adenovirus-7 (HAdV-7) occurred among unvaccinated officer candidates attending initial military training. Respiratory infections associated with HAdV-7 can be severe resulting in significant morbidity. Genomic sequencing revealed HAdV-7d, a genome type recently remerging in the US as a significant respiratory pathogen, following reports from Southeast Asia. Twenty-nine outbreak cases were identified; this likely represents an underestimate. Although the HAdV-4 and -7 vaccine is currently given to US military enlisted recruit trainees, it is not routinely given to officer candidates. Administration of the HAdV-4 and -7 vaccine may benefit this cohort.