MMWR Morb Mortal Wkly Rep. 2021 Jan 29;70(4):130-135. doi: 10.15585/mmwr.mm7004e2.
The National Football League (NFL) and the NFL Players Association (NFLPA) began the 2020 football season in July, implementing extensive mitigation and surveillance measures in facilities and during travel and gameplay. Mitigation protocols* were evaluated and modified based on data from routine reverse transcription-polymerase chain reaction (RT-PCR) tests for SARS-CoV-2, the virus that causes coronavirus 2019 (COVID-19); proximity tracking devices; and detailed interviews. Midseason, transmission was observed in persons who had cumulative interactions of <15 minutes' duration, leading to a revised definition of high-risk contacts that required consideration of mask use, setting and room ventilation in addition to proximity and duration of interaction. The NFL also developed an intensive protocol that imposed stricter infection prevention precautions when a case was identified at an NFL club. The intensive protocol effectively prevented the occurrence of high-risk interactions, with no high-risk contacts identified for 71% of traced cases at clubs under the intensive protocol. The incorporation of the nature and location of the interaction, including mask use, indoor versus outdoor setting, and ventilation, in addition to proximity and duration, likely improved identification of exposed persons at higher risk for SARS-CoV-2 infection. Quarantine of these persons, along with testing and intensive protocols, can reduce spread of infection.
美国国家橄榄球联盟（NFL）和全美橄榄球运动员协会（NFLPA）于 2020 年 7 月开始新赛季，在设施内以及旅行和比赛期间实施了广泛的缓解和监测措施。根据对导致 2019 年冠状病毒病（COVID-19）的 SARS-CoV-2 的常规逆转录-聚合酶链反应（RT-PCR）检测、近距离追踪设备以及详细访谈获得的数据，对缓解协议进行了评估和修改。赛季中期，在累积接触时间<15 分钟的人群中观察到了传播，这导致对高风险接触者的定义进行了修订，修订后的定义除了考虑接触的距离和时间外，还需要考虑戴口罩、环境和房间通风情况。NFL 还制定了一项强化方案，在 NFL 俱乐部发现病例时采取更严格的感染预防措施。强化方案有效地防止了高风险接触的发生，在实施强化方案的俱乐部中，71%的追踪病例没有发现高风险接触者。除了接触的距离和时间外，还考虑了接触的性质和地点，包括戴口罩、室内还是室外环境以及通风情况，这可能有助于更好地识别有较高感染 SARS-CoV-2 风险的接触者。对这些人进行隔离以及检测和强化方案，可以减少感染的传播。
