An outbreak of coronavirus disease 2019 (Covid-19) occurred on the U.S.S. Theodore Roosevelt, a nuclear-powered aircraft carrier with a crew of 4779 personnel.
We obtained clinical and demographic data for all crew members, including results of testing by real-time reverse-transcriptase polymerase chain reaction (rRT-PCR). All crew members were followed up for a minimum of 10 weeks, regardless of test results or the absence of symptoms.
The crew was predominantly young (mean age, 27 years) and was in general good health, meeting U.S. Navy standards for sea duty. Over the course of the outbreak, 1271 crew members (26.6% of the crew) tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection by rRT-PCR testing, and more than 1000 infections were identified within 5 weeks after the first laboratory-confirmed infection. An additional 60 crew members had suspected Covid-19 (i.e., illness that met Council of State and Territorial Epidemiologists clinical criteria for Covid-19 without a positive test result). Among the crew members with laboratory-confirmed infection, 76.9% (978 of 1271) had no symptoms at the time that they tested positive and 55.0% had symptoms develop at any time during the clinical course. Among the 1331 crew members with suspected or confirmed Covid-19, 23 (1.7%) were hospitalized, 4 (0.3%) received intensive care, and 1 died. Crew members who worked in confined spaces appeared more likely to become infected.
SARS-CoV-2 spread quickly among the crew of the U.S.S. Theodore Roosevelt. Transmission was facilitated by close-quarters conditions and by asymptomatic and presymptomatic infected crew members. Nearly half of those who tested positive for the virus never had symptoms.
4779名の乗組員を擁する原子力空母セオドア・ルーズベルト号(U.S.S.Theodore Roosevelt)Covid-19のアウトブレイクが発生した。
rRT-PCRによる検査結果を含む、全乗組員の臨床データおよび人口統計学的データを取得した。すべての乗組員は、検査結果や症状の有無にかかわらず、最低 10 週間の追跡調査を行った。
乗組員は若年者が多く(平均年齢27歳)、健康状態は全般的に良好で、米国海軍の海上勤務の基準を満たしていた。発生期間中、1271名(乗組員の26.6%)の乗組員がrRT-PCR検査でSARS-CoV-2に陽性反応を示し、検査で確認された最初の感染から5週間以内に1000名以上の感染が確認された。さらに60名の乗組員がCovid-19疑いでああった(すなわち、Covid-19の臨床基準を満たしていたが、検査結果が陽性ではなかった)。検査で感染が確認された乗組員のうち、76.9%(1271人中978人)が陽性反応を示した時点では症状がなく、55.0%が臨床経過中のいずれかの時点で症状が発現していた。Covid-19疑いまたは陽性の1331人の乗組員のうち、23人(1.7%)が入院し、4人(0.3%)が集中治療を受け、1人が死亡した。限られた空間で作業していた乗組員は感染する可能性が高いようであった。
SARS-CoV-2 は U.S.S.セオドア・ルーズベルト号の乗組員の間で急速に広まった。感染は、乗組員との距離が近いことと、無症候性および症状発現前の感染者の乗組員によって促進された。ウイルス陽性と判定された乗組員のほぼ半数には症状が見られなかった。
https://www.nejm.org/doi/pdf/10.1056/NEJMoa2019375?articleTools=true