Epidemiological characteristics of coronavirus disease 2019 outbreak in Ganzr Tibetan Autonomous Prefecture, Sichuan

ObjectiveTo understand the epidemiological characteristics of coronavirus disease 2019 (COVID-19) outbreak in Ganzr Tibetan Autonomous Prefecture of Sichuan province in 2020 and provide scientific evidence for the control of local epidemic and the prevention of imported epidemic.

MethodsEpidemiological survey and respiratory tract sample collection were conducted according to “Protocol of prevention and control of novel coronavirus 2019” and “Management protocol of suspected exposure (to) and close contact with COVID-19 cases (2rd edition)”. Real time RT-PCR was used for the nucleic acid detection of 2019-nCoV, and descriptive epidemiological analysis on cases’ characteristics, epidemic trend and influencing factors were conducted.

ResultsA total of 682 close contacts of 54 COVID-19 cases were investigated, in which 39 confirmed cases and 3 asymptomatic cases were detected. As of February 28, 2020, a total of 96 COVID-19 cases, including 78 confirmed cases and 18 asymptomatic cases, had been reported in Ganzr Tibetan Autonomous Prefecture. The epidemic was caused by 5 imported cases who had sojourn history in Wuhan. Further spread of COVID-19 resulted from the gathering of 73 local confirmed cases and 18 asymptomatic cases.

ConclusionA total of 96 COVID-19 cases were reported in the outbreak in Ganzr Tibetan Autonomous Prefecture. Household contact and religious ceremony（dharma assembly in temple and traditional funeral rites）were considered as the high-risk infection ways. Most asymptomatic cases were young or middle-aged adults. Strict isolation of close contacts, timely nucleic acid detection of 2019-nCoV for asymptomatic persons in close contacts and high-quality timely treatment for old-aged confirmed cases could effectively reduce the morbidity and mortality of COVID-19.