The crew was predominantly young (mean age, 27 years) and male (78.3%) and was racially and ethnically diverse. At the time of deployment, all crew members were in general good health and met the U.S. Navy standards for sea duty. Ultimately, Covid-19 cases were evenly distributed across sexes, races and ethnic groups, and crew types (Table 1). Enlisted personnel (90% of the shipboard population) appeared more likely than officers to have confirmed or suspected Covid-19.