Department of Environmental Health, Harvard T.H. Chan School of Public Heath, Boston, Massachusetts.
Veterans Affairs Boston Healthcare System, West Roxbury, Boston, Massachusetts.
JAMA Netw Open. 2022 Jun 1;5(6):e2216176. doi: 10.1001/jamanetworkopen.2022.16176.
Aerosol-borne SARS-CoV-2 has not been linked specifically to nosocomial outbreaks.
To explore the genomic concordance of SARS-CoV-2 from aerosol particles of various sizes and infected nurses and patients during a nosocomial outbreak of COVID-19.
DESIGN, SETTING, AND PARTICIPANTS: This cohort study included patients and nursing staff in a US Department of Veterans Affairs inpatient hospital unit and long-term-care facility during a COVID-19 outbreak between December 27, 2020, and January 8, 2021. Outbreak contact tracing was conducted using exposure histories and screening with reverse transcriptase-polymerase chain reaction (RT-PCR) for SARS-CoV-2. Size-selective particle samplers were deployed in diverse clinical areas of a multicampus health care system from November 2020 to March 2021. Viral genomic sequences from infected nurses and patients were sequenced and compared with ward nurses station aerosol samples.
SARS-CoV-2.
The primary outcome was positive RT-PCR results and genomic similarity between SARS-CoV-2 RNA in aerosols and human samples. Air samplers were used to detect SARS-CoV-2 RNA in aerosols on hospital units where health care personnel were or were not under routine surveillance for SARS-CoV-2 infection.
A total of 510 size-fractionated air particle samples were collected. Samples representing 3 size fractions (>10 μm, 2.5-10 μm, and <2.5 μm) obtained at the nurses station were positive for SARS-CoV-2 during the outbreak (3 of 30 samples [10%]) and negative during 9 other collection periods. SARS-CoV-2 partial genome sequences for the smallest particle fraction were 100% identical with all 3 human samples; the remaining size fractions shared >99.9% sequence identity with the human samples. Fragments of SARS-CoV-2 RNA were detected by RT-PCR in 24 of 300 samples (8.0%) in units where health care personnel were not under surveillance and 7 of 210 samples (3.3%; P = .03) where they were under surveillance.
In this cohort study, the finding of genetically identical SARS-CoV-2 RNA fragments in aerosols obtained from a nurses station and in human samples during a nosocomial outbreak suggests that aerosols may have contributed to hospital transmission. Surveillance, along with ventilation, masking, and distancing, may reduce the introduction of community-acquired SARS-CoV-2 into aerosols on hospital wards, thereby reducing the risk of hospital transmission.
气溶胶传播的 SARS-CoV-2 尚未与医院内爆发明确相关。
探索在 COVID-19 医院内爆发期间，各种大小的气溶胶颗粒以及感染的护士和患者的 SARS-CoV-2 的基因组一致性。
设计、地点和参与者：本队列研究纳入了 2020 年 12 月 27 日至 2021 年 1 月 8 日期间，美国退伍军人事务部住院医院病房和长期护理机构中的患者和护理人员。通过接触史和逆转录酶-聚合酶链反应（RT-PCR）筛查对 COVID-19 爆发进行了接触追踪。从 2020 年 11 月至 2021 年 3 月，在一个多校区医疗保健系统的不同临床区域部署了大小选择粒子采样器。对感染的护士和患者的病毒基因组序列进行了测序，并与病房护士站气溶胶样本进行了比较。
SARS-CoV-2。
主要结果是 SARS-CoV-2 RNA 在气溶胶和人体样本中的阳性 RT-PCR 结果和基因组相似性。空气采样器用于检测医院病房中 SARS-CoV-2 空气颗粒，这些病房中的医护人员正在或未进行常规 SARS-CoV-2 感染监测。
共收集了 510 个大小分级的空气颗粒样本。在爆发期间，护士站采集的代表 3 个大小分数（>10 μm、2.5-10 μm 和 <2.5 μm）的样本均呈 SARS-CoV-2 阳性（30 个样本中的 3 个 [10%]），而在其他 9 个采集期均为阴性。最小颗粒分数的 SARS-CoV-2 部分基因组序列与所有 3 个人类样本完全相同；其余大小分数与人类样本共享>99.9%的序列同一性。在未进行监测的医护人员所在的 300 个样本中有 24 个（8.0%）和在进行监测的 210 个样本中有 7 个（3.3%；P = .03）检测到 SARS-CoV-2 RNA 的 RT-PCR 片段。
在这项队列研究中，从护士站获得的气溶胶中与在医院内爆发期间从人类样本中获得的 SARS-CoV-2 的遗传上相同的 RNA 片段的发现表明，气溶胶可能导致了医院内的传播。监测以及通风、掩蔽和距离隔离，可能会减少社区获得性 SARS-CoV-2 引入医院病房空气中，从而降低医院内传播的风险。
