To determine risk factors for coronavirus disease (COVID-19) among US healthcare personnel (HCP), we conducted a case–control analysis. We collected data about activities outside the workplace and COVID-19 patient care activities from HCP with positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) test results (cases) and from HCP with negative test results (controls) in healthcare facilities in 5 US states. We used conditional logistic regression to calculate adjusted matched odds ratios and 95% CIs for exposures. Among 345 cases and 622 controls, factors associated with risk were having close contact with persons with COVID-19 outside the workplace, having close contact with COVID-19 patients in the workplace, and assisting COVID-19 patients with activities of daily living. Protecting HCP from COVID-19 may require interventions that reduce their exposures outside the workplace and improve their ability to more safely assist COVID-19 patients with activities of daily living.

为了确定美国医护人员 (HCP) 感染冠状病毒 (COVID-19) 的危险因素，我们进行了病例对照分析。我们从医疗机构中严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 检测结果呈阳性的 HCP（病例）和检测结果呈阴性的 HCP（对照）收集了有关工作场所外活动和 COVID-19 患者护理活动的数据在美国 5 个州。我们使用条件逻辑回归来计算调整后的匹配比值比和暴露的 95% CI。在 345 例病例和 622 例对照中，与风险相关的因素包括在工作场所外与 COVID-19 患者密切接触、在工作场所与 COVID-19 患者密切接触以及协助 COVID-19 患者进行日常生活活动。保护 HCP 免受 COVID-19 感染可能需要采取干预措施，减少他们在工作场所之外的接触，并提高他们更安全地帮助 COVID-19 患者进行日常生活活动的能力。