Three infection clusters related with potential pre-symptomatic transmission of coronavirus disease (COVID-19), Shanghai, China, January to February 2020 Gong, Xiaohuan and Xiao, Wenjia and Cui, Yan and Wang, Yuanping and Kong, Dechuan and Mao, Shenghua and Zheng, Yaxu and Xiang, Lunhui and Lu, Lu and Jiang, Chenyan and Yu, Xiao and Zhu, Yiyi and Fang, Qiwen and Pan, Hao and Wu, Huanyu, Eurosurveillance, 25, 2000228 (2020), https://doi.org/10.2807/1560-7917.ES.2020.25.33.2000228