Indoor transmission of SARS-CoV-2

Hua Qian; Te Miao; Li LIU; Xiaohong Zheng; Danting Luo; Yuguo Li

A total of 7324 cases with the minimum required descriptions (i.e., the information listed above) were found; these accounted for 66.7% of the 10,980 confirmed non-Hubei cases in China by 11 February 2020. 3 In this study, we defined a cluster as an aggregation of three or more cases that appears to be linked to the same infection venue (e.g., an apartment, an office, a school or a train) during a sufficiently close period. We defined an outbreak as a cluster in which a common index patient is suspected, and we excluded tertiary and highergeneration infections in counting the number of cases involved. We also excluded outbreaks that involved only two cases to exclude possible spouse-to-spouse transmission and to reduce the workload due to the large number of clusters or outbreaks with two cases. We also identified the index patient(s) of the identified outbreaks and their date of symptom onset.