A descriptive study of the impact of diseases control and prevention on the epidemics dynamics and clinical features of SARS-CoV-2 outbreak in Shanghai, lessons learned for metropolis epidemics prevention

Hongzhou Lu; Jingwen Ai; Yinzhong Shen; Yang Li; Tao Li; Xian Zhou; Haocheng Zhang; Qiran Zhang; Yun Ling; Sheng Wang; Hongping Qu; Yuan Gao; Yingchuan Li; Kanglong Yu; Duming Zhu; Hecheng Zhu; Rui Tian; Mei Zeng; Qiang Li; Yuanlin Song; Xiangyang Li; Jinfu Xu; Jie Xu; Enqiang Mao; Bijie Hu; Xin Li; Lei Zhu; Wenhong Zhang

The copyright holder for this preprint (which was not peer-reviewed) is . https://doi.org /10.1101 /10. /2020 we could find out that Shanghai exhibited a high-efficiency epidemics controlling ability and 257 had stopped the exponential growth for now. The reason behind this is that during this 258 epidemic, Chinese and Shanghai government has issued very strong and strict measures 259 in restricting the transmission in local regions. The national transport department 260 announced a 45% and 70.6% decline in the passenger flow at the beginning and the end 261 of 2020 Spring Festival, respectively [13] [14] . What's more, Shanghai government 262 cancelled all gathering activities and through propaganda of the officials, media and 263 community, citizens were well-informed and well-educated of the importance of wearing 264 face masks and washing hands frequently. Previous studies have suggested that the 265 mobility reduction could not effectively lower the incidence rate while 50% transmissibility 266 reduction could easily prevent the epidemics from further spreading [12] . In the case of 267 Shanghai, the transmissibility was indeed greatly reduced, however, we believe the 268 mobility reduction also played an indirect role in lowering the transmissibility. This is 269 because that Chinese Spring Festival is characterized by hundreds of millions of people 270 transporting from one region to another, and this massive gathering at the airports, train 271 stations during transportation, if not controlled, would significantly increase the human to 272 human transmission. Therefore, during this special period, controlling both mobility and 273 transmissibility might be important. Other doubt lies in that previous studies have reported 274 that the ascertainment rate in Wuhan is 5.1% [11] , and suggested that other cities such as 275 Shanghai, Beijing have the similar ascertainment rate, which would lead to our local case 276 numbers fall below the true ones. However, in Shanghai for example, the suspected cases 277