Katz Morgan J, Reeves Majerle, Harris Tiffany G, Duque Jazmin, Fridkin Scott K, Rebolledo Paulina A, Furuno Jon P, Short Emily K, Canaday David H, Abul Yasin, Gravenstein Stefan, Cosgrove Sara E, Mody Lona, Meddings Jennifer, Nace David A, Handler Steven, Crnich Christopher J, Meece Jennifer, Webby Richard J, Fabrizio Tom P, Harcourt Jennifer L, Healy Jessica M, Lipsitch Marc, Lutgring Joseph D, Paul Prabasaj, Zipfel Casey M, Hernandez-Romieu Alfonso C, Reddy Sujan C, Slayton Rachel B
Department of Medicine, Johns Hopkins University, Baltimore, Maryland, USA.
Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.
J Am Geriatr Soc. 2025 Jul;73(7):2127-2136. doi: 10.1111/jgs.19499. Epub 2025 May 2.
Nursing homes (NHs) were disproportionately affected by the COVID-19 pandemic. However, little is known regarding the kinetics of SARS-CoV-2 shedding in NH residents and staff, which could inform treatment and infection prevention.
We enrolled NH residents and staff in eight US states from April to November 2023 and analyzed the kinetics of SARS-CoV-2 using serial antigen and molecular (RT-PCR) tests, whole genome sequencing, and viral culture (VC). Symptoms, vaccination, and treatment were collected via interviews and chart review. Viral load trajectories were modeled with gamma distribution functional forms. Antigen and VC test positivity over time were assessed using a Chi-squared test.
Of the 587 enrolled participants, 86 tested positive and 73 underwent testing for ≥ 10 days; most residents (78%) and staff (87%) had ≥ 3 COVID-19 vaccine doses. The modeled SARS-CoV-2 proliferation period (period prior to reaching peak viral load) had ended for 48% (14/29) of residents and 56% (9/16) of staff when they took the initial RT-PCR test. Both antigen and VC showed higher positivity rates early in the course of disease (Days 0-5 vs. Days ≥ 6) (antigen: p < 0·001, VC: p < 0·001). VC positivity was 15% after Day 5 (14/96); two participants were VC positive after Day 10.
Peak viral load occurs early in the disease, suggesting asymptomatic and presymptomatic transmission may be a significant driver of transmission. Only two participants had a positive VC after Day 10, supporting current isolation and return to work recommendations.
养老院（NHs）在新冠疫情中受到的影响尤为严重。然而，关于养老院居民和工作人员中新冠病毒脱落的动力学情况知之甚少，而这可为治疗和感染预防提供依据。
我们在2023年4月至11月期间招募了美国八个州的养老院居民和工作人员，并通过系列抗原和分子（逆转录聚合酶链反应，RT-PCR）检测、全基因组测序和病毒培养（VC）来分析新冠病毒的动力学情况。通过访谈和病历审查收集症状、疫苗接种和治疗情况。用伽马分布函数形式对病毒载量轨迹进行建模。使用卡方检验评估抗原和病毒培养检测随时间的阳性率。
在587名登记参与者中，86人检测呈阳性，73人接受了≥10天的检测；大多数居民（78%）和工作人员（87%）接种了≥3剂新冠疫苗。当居民和工作人员进行首次RT-PCR检测时，其新冠病毒增殖期（达到病毒载量峰值之前的时期）对48%（14/29）的居民和56%（9/16）的工作人员来说已经结束。抗原和病毒培养在疾病早期（第0 - 5天与≥6天）均显示出更高的阳性率（抗原：p < 0.001，病毒培养：p < 0.001）。第5天后病毒培养阳性率为15%（14/96）；两名参与者在第10天后病毒培养呈阳性。
病毒载量峰值在疾病早期出现，这表明无症状和症状前传播可能是传播的一个重要驱动因素。只有两名参与者在第10天后病毒培养呈阳性，这支持了当前的隔离和复工建议。
