Infectious droplet exposure is an inefficient route for SARS-CoV-2 infection in the ferret model
Infectious droplet exposure is an inefficient route for SARS-CoV-2 infection in the ferret model
复制标题
DOI：
10.1099/jgv.0.001799
复制
发表时间：
2022-01-01
影响因子：
3.8
通讯作者：
Brookes, Sharon M.
中科院分区：
文献类型：
--
作者：
James, Joe;Byrne, Alexander M. P.;Brookes, Sharon M.
严重急性呼吸综合征冠状病毒2型（SARS-CoV-2）是2019年人类冠状病毒病（COVID-19）的病原体，具有广泛的宿主范围，可自然感染猫科动物、犬科动物、家畜、啮齿动物和鼠类。人们普遍认为，SARS-CoV-2是通过直接或间接接触呼吸道上皮污染的分泌物传播的。在一些人类和实验动物病例中，也有通过咳嗽或打喷嚏产生的飞沫核传播的报告。然而，在人-动物界面的飞沫传播的作用仍有待充分阐明。本研究采用雪貂感染模型研究SARS-CoV-2 β变体（B.1.351）的感染途径。雪貂暴露在含有传染性SARS-CoV-2的飞沫中，直径在4到106 μ m之间，模拟感染者咳嗽产生的更大的飞沫。暴露后，在雪貂的皮毛上检测到病毒RNA，并沉积在环境表面以及直接接触雪貂的皮毛上；SARS-CoV-2在皮毛上至少保持48小时的传染性。在接触后早期的鼻洗液中检测到低水平的病毒RNA，但没有直接接触或直接接触的雪貂被强烈感染或血清转化为SARS-CoV-2。相比之下，经鼻内接种SARS-CoV-2 β变体的雪貂被强烈感染，从鼻腔排出病毒RNA和传染性病毒，75%直接接触的天真雪貂被传播。这些数据表明，较大的传染性飞沫核和受污染的皮毛在mustelids和其他可能的伴侣动物之间的SARS-CoV-2传播中起着次要作用。
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19) in humans, has a wide host range, naturally infecting felids, canids, cervids, rodents and mustelids. Transmission of SARS-CoV-2 is universally accepted to occur via contact with contaminated secretions from the respiratory epithelium, either directly or indirectly. Transmission via droplet nuclei, generated from a cough or sneeze, has also been reported in several human and experimental animal scenarios. However, the role of droplet transmission at the human-animal interface remains to be fully elucidated. Here, the ferret infection model was used to investigate the routes of infection for the SARS-CoV-2 beta variant (B.1.351). Ferrets were exposed to droplets containing infectious SARS-CoV-2, ranging between 4 and 106 mu m in diameter, simulating larger droplets produced by a cough from an infected person. Following exposure, viral RNA was detected on the fur of ferrets, and was deposited onto environmental surfaces, as well as the fur of ferrets placed in direct contact; SARS-CoV-2 remained infectious on the fur for at least 48 h. Low levels of viral RNA were detected in the nasal washes early post-exposure, yet none of the directly exposed, or direct-contact ferrets, became robustly infected or seroconverted to SARS-CoV-2. In comparison, ferrets intranasally inoculated with the SARS-CoV-2 beta variant became robustly infected, shedding viral RNA and infectious virus from the nasal cavity, with transmission to 75% of naive ferrets placed in direct contact. These data suggest that larger infectious droplet nuclei and contaminated fur play minor roles in SARS-CoV-2 transmission among mustelids and potentially other companion animals.