Indirect Virus Transmission in Cluster of COVID-19 Cases, Wenzhou, China, 2020

Abstract

To determine possible modes of virus transmission, we investigated a cluster of coronavirus disease cases associated with a shopping mall in Wenzhou, China. Data indicated that indirect transmission of the causative virus occurred, perhaps resulting from virus contamination of common objects, virus aerosolization in a confined space, or spread from asymptomatic infected persons.

Keywords: 2019 novel coronavirus disease; COVID-19; China; SARS-CoV-2; Wenzhou; aerosolization; cluster; coronavirus; respiratory infections; severe acute respiratory syndrome coronavirus 2; viruses; zoonoses.

Figure

Cluster of COVID-19 cases associated with a shopping mall in Wenzhou, China. A) Distribution of COVID-19 case-patients by mall floor, time, and internal relationship. B) Dates of symptom onset, confirmed test results, and hospitalization information. Numbers within yellow bars indicate length of incubation period. Black vertical arrow indicates date when patient A returned from Wuhan, China. B1–7, mall floors; C, customer; COVID-19, coronavirus disease; C_t, cycle threshold; T, date of symptom onset; M, month; RT-PCR, reverse transcription PCR.