Abstract:
Objective To examine the characteristics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) contamination on inanimate surfaces in working and living places of the cases and asymptomatic individuals with coronavirus disease 2019 (COVID-19) infection and to provide references for the prevention and control of the disease.
Methods Inanimate surface swab specimens were collected in working and living places of 68 confirmed COVID-19 patients and asymptomatic cases on the day of the first positive detection of SARS-CoV-2 nucleic acid during March – May 2020 in Yuexiu district of Guangzhou city. The specimens were detected for SARS-CoV-2 nucleic acid with real-time reverse transcriptase – polymerase chain reaction (RT-PCR). Chi-square test and Fisher′s exact test were used to analyze the difference in positive rates of the specimens.
Results For a total of 839 specimens detected, the positive rate of SARS-CoV-2 nucleic acid was 12.44% (54/434) before terminal disinfections of ambient environments and the positive rate was significantly higher than that (0.49%, 2/405) after the terminal disinfections (χ2 = 48.016, P < 0.001). Before terminal disinfections, there was no difference in positive rates between the specimens collected in living environments of confirmed cases and asymptomatic individuals (χ2 = 2.378, P = 0.123). No positive specimen was detected in working environments. Among all the specimens collected in living environments, the positive rate (22.82%) was the highest for the specimens collected in bathrooms, followed by those collected in living rooms/bedrooms (14.80%), and public spaces (0.88%) and all specimens collected in kitchens were negative. For all the swab specimens of 11 kinds of appliances and articles, the positive rate was the highest (23.75%) for the specimens of toilet articles.
Conclusion There are various extents of SARS-CoV-2 contamination on inanimate surfaces in working and living environments surrounding COVID-19 cases and asymptomatic infected individuals in Guangzhou city and the contamination is the worst in restroom environment.