Prevalence of SARS-CoV-2 contamination on food plant surfaces as determined by environmental monitoring.

Ming, Ziwen; Han, Sukkyun; Deng, Kai; Reyes, Enrique; Ha, Youngsil; Kim, SungSoo; Zhao, Yu; Dobritsa, Anatoly; Wu, Meiting; Zhang, Dandan; Cox, David P; Joyner, Emma; Kulasekara, Hemantha; Kim, Seong Hong; Jang, Yong Seog; Fowler, Curtis; Fei, Xing; Akasaki, Hikari; Themeli, Eni; Agapov, Alexander; Bruneau, Dylan; Tran, Thao; Szczesny, Cameron; Kienzle, Casey; Tenney, Kristina; Geng, Hao; Myoda, Samuel; Samadpour, Mansour

The SARS-CoV-2 pandemic has presented new challenges to food manufacturers. During the early phase of the pandemic, several large outbreaks of Covid-19 occurred in food manufacturing plants resulting in deaths and economic loss, with approximately 15% of personnel diagnosed as asymptomatic for Covid-19. Disease spread by asymptomatic and presymptomatic individuals have been implicated for large outbreaks of Covid-19. In March of 2020, we assisted in implementation of environmental monitoring programs for SARS-CoV-2 in zones three and four of 116 food production facilities. All participating facilities had already implemented measures to prevent symptomatic personnel from coming to work. During the study period, from March 17, 2020 to September 3, 2020, 1.23% of the 22,643 environmental samples tested positive for SARS-CoV-2, suggesting that infected individuals were actively shedding virus. Virus contamination was commonly found on frequently touched surfaces such as doorknobs, handles, table surfaces and sanitizer dispensers. Most plants managed to control their environmental contamination when they became aware of the positive findings. Comparisons of positive test results of plant personnel and environmental surfaces in one plant showed a good correlation between the two. Our work illustrates that environmental monitoring for SARS-CoV-2 can be used as a surrogate for identifying the presence of asymptomatic and pre-symptomatic personnel in workplaces and may aid in controlling infection spread.