外科口罩分区降低了 2019 冠状病毒病（COVID-19）金黄地鼠模型中非接触传播的风险。

Surgical Mask Partition Reduces the Risk of Noncontact Transmission in a Golden Syrian Hamster Model for Coronavirus Disease 2019 (COVID-19).

机构信息

State Key Laboratory of Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China.

Department of Clinical Microbiology and Infection Control, The University of Hong Kong-Shenzhen Hospital, Shenzhen, Guangdong, China.

出版信息

Clin Infect Dis. 2020 Nov 19;71(16):2139-2149. doi: 10.1093/cid/ciaa644.

DOI:10.1093/cid/ciaa644

PMID:32472679

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7314229/

Abstract

BACKGROUND

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is believed to be mostly transmitted by medium- to large-sized respiratory droplets, although airborne transmission may be possible in healthcare settings involving aerosol-generating procedures. Exposure to respiratory droplets can theoretically be reduced by surgical mask usage. However, there is a lack of experimental evidence supporting surgical mask usage for prevention of COVID-19.

METHODS

We used a well-established golden Syrian hamster SARS-CoV-2 model. We placed SARS-CoV-2-challenged index hamsters and naive hamsters into closed system units each comprising 2 different cages separated by a polyvinyl chloride air porous partition with unidirectional airflow within the isolator. The effect of a surgical mask partition placed between the cages was investigated. Besides clinical scoring, hamster specimens were tested for viral load, histopathology, and viral nucleocapsid antigen expression.

RESULTS

Noncontact transmission was found in 66.7% (10/15) of exposed naive hamsters. Surgical mask partition for challenged index or naive hamsters significantly reduced transmission to 25% (6/24, P = .018). Surgical mask partition for challenged index hamsters significantly reduced transmission to only 16.7% (2/12, P = .019) of exposed naive hamsters. Unlike the severe manifestations of challenged hamsters, infected naive hamsters had lower clinical scores, milder histopathological changes, and lower viral nucleocapsid antigen expression in respiratory tract tissues.

CONCLUSIONS

SARS-CoV-2 could be transmitted by respiratory droplets or airborne droplet nuclei which could be reduced by surgical mask partition in the hamster model. This is the first in vivo experimental evidence to support the possible benefit of surgical mask in prevention of COVID-19 transmission, especially when masks were worn by infected individuals.

摘要

背景

由严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）引起的 2019 年冠状病毒病（COVID-19）据信主要通过中到大呼吸道飞沫传播，尽管在涉及产生气溶胶的程序的医疗保健环境中可能存在空气传播。使用外科口罩可理论上减少对呼吸道飞沫的接触。然而，缺乏支持使用外科口罩预防 COVID-19 的实验证据。

方法

我们使用了一种成熟的金黄地鼠 SARS-CoV-2 模型。我们将 SARS-CoV-2 感染的指数仓鼠和未感染的仓鼠放入封闭系统单元中，每个单元包含 2 个不同的笼子，通过聚氯乙烯空气多孔隔板隔开，隔离器内的空气呈单向流动。研究了放置在笼子之间的外科口罩隔板的效果。除了临床评分外，还对仓鼠标本进行了病毒载量、组织病理学和病毒核衣壳抗原表达检测。

结果

在 66.7%（10/15）的暴露于未感染的仓鼠中发现了非接触传播。对于受感染的指数或未感染的仓鼠使用外科口罩隔板可将传播率降低至 25%（6/24，P =.018）。对于受感染的指数仓鼠使用外科口罩隔板可将传播率降低至仅 16.7%（2/12，P =.019）。与受感染仓鼠的严重表现不同，感染的未感染仓鼠的临床评分较低，呼吸道组织的组织病理学变化较轻，病毒核衣壳抗原表达水平较低。