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bioRxiv · 10.1101/2020.07.09.195008

Air and surface contamination in non-health care settings among 641 environmental specimens of 39 COVID-19 cases

Lei Luo [PhD]·Dan Liu [PhD]·Hao Zhang [MSc]·Zhihao Li [PhD]·Ruonan Zhen [MSc]·Xiru Zhang [PhD]·Huaping Xie [MSc]·Weiqi Song [MSc]·Jie Liu [MSc]·Qingmei Huang [MSc]·Jingwen Liu [MSc]·Xingfen Yang [PhD]·Zongqiu Chen [PhD]·Chen Mao [PhD]
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Abstract

BackgroundLittle is known about the SARS-CoV-2 contamination of environmental surfaces and air in non-health care settings among COVID-19 cases. Methods and findingsWe explored the SARS-CoV-2 contamination of environmental surfaces and air by collecting air and swabbing environmental surfaces among 39 COVID-19 cases in Guangzhou, China. The specimens were tested by RT-PCR testing. The information collected for COVID-19 cases included basic demographic, clinical severity, onset of symptoms, radiological testing, laboratory testing and hospital admission. A total of 641 environmental surfaces and air specimens were collected among 39 COVID-19 cases before disinfection. Among them, 20 specimens (20/641, 3.1%) were tested positive from 9 COVID-19 cases (9/39, 23.1%), with 5 (5/101, 5.0%) positive specimens from 3 asymptomatic cases, 5 (5/220, 2.3%) from 3 mild cases, and 10 (10/374, 2.7%) from 3 moderate cases. All positive specimens were collected within 3 days after diagnosis, and 10 (10/42, 23.8%) were found in toilet (5 on toilet bowl, 4 on sink/faucet/shower, 1 on floor drain), 4 (4/21, 19.0%) in anteroom (2 on water dispenser/cup/bottle, 1 on chair/table, 1 on TV remote), 1 (1/8, 12.5%) in kitchen (1 on dining-table), 1 (1/18, 5.6%) in bedroom (1 on bed/sheet pillow/bedside table), 1 (1/5, 20.0%) in car (1 on steering wheel/seat/handlebar) and 3 (3/20, 21.4%) on door knobs. Air specimens in room (0/10, 0.0%) and car (0/1, 0.0%) were all negative. ConclusionsSARS-CoV-2 was found on environmental surfaces especially in toilet, and could survive for several days. We provided evidence of potential for SARS-CoV-2 transmission through contamination of environmental surfaces.

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Lei Luo [PhD], Dan Liu [PhD], Hao Zhang [MSc], Zhihao Li [PhD], Ruonan Zhen [MSc], Xiru Zhang [PhD], Huaping Xie [MSc], Weiqi Song [MSc], Jie Liu [MSc], Qingmei Huang [MSc], Jingwen Liu [MSc], Xingfen Yang [PhD], Zongqiu Chen [PhD], Chen Mao [PhD]. 2020-07-09. Air and surface contamination in non-health care settings among 641 environmental specimens of 39 COVID-19 cases. https://doi.org/10.1101/2020.07.09.195008

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