Evolving Epidemiology and Impact of Non-pharmaceutical Interventions on the Outbreak of Coronavirus Disease 2019 in Wuhan, China

Chaolong Wang; Li Liu; Xingjie Hao; Huan Guo; Qi Wang; Jiao Huang; Na He; Hongjie Yu; Xihong Lin; An Pan; Sheng Wei; Tangchun Wu

is the (which was not peer-reviewed) The copyright holder for this preprint . https://doi.org/10.1101/2020.03.03.20030593 doi: medRxiv preprint and was expected to accelerate the spread of Covid-19. No strong intervention was imposed except for the announcement of human-to-human transmission and infections in healthcare workers on January 20. The hospitals started to be overcrowded with people with fever or respiratory symptoms. During the third period between January 23 and February 1, the local government first blocked all outbound transportations on January 23 and subsequently suspended public transit and banned all vehicular traffic within the city. Other social distancing measures were also implemented, including compulsory mask-wearing in public places and cancellation of social gathering. Due to severe shortage of medical resources in this period, many confirmed or suspected cases could not receive timely treatment and were self-quarantined at home. On February 2, with improvement in medical resources, the government implemented the policy of centralized quarantine and treatment of all confirmed and suspected cases, those with fever or respiratory symptoms, as well as close contacts of confirmed cases in designated hospitals or facilities. Meanwhile, temperature monitoring and stay-at-home policies were implemented to all residents in the city. Taken together, we divided the outbreak in Wuhan into four periods (before January 11, January 11-22, January 23-February 1, and February 2-18, 2020, respectively) with specific intervention activities provided in Fig. 1 .