Is a 14-day quarantine period optimal for effectively controlling coronavirus disease 2019 (COVID-19)?

Xue Jiang; Yawei Niu; Xiong Li; Lin Li; Wenxiang Cai; Yucan Chen; Bo Liao; Edwin Wang

SARS-CoV-2 can be transmitted by either respiratory droplets, contaminated surfaces, and objects or an oral-fecal transmission route to lead gastrointestinal tract infection 1 Because outbreaks are being occurred in many countries, it is critical to analyze real-time data of the Covid-19 cases to gain insights to inform public-health intervention strategies for managing and preventing the disease. One of the key issues for controlling Covid-19 is to set up a suitable quarantine period which could capture about 95% of the cases developing symptoms so that the practice of isolations will be more effective and save public health resources. Thus far, the incubation time studies have been focused on hospitalized patients who were highly selected based on medical conditions, and further, sample sizes for inferring incubation times were small, for example, 10 and ~100, respectively 3, 4 . However, the majority (i.e., about 80% of adults and 95% of children) of the Covid-19 cases were not necessary to be hospitalized, and therefore, had not been hospitalized due to their mild conditions. Here, we asked if the median incubation time inferred from the hospitalized patients are representative for the whole population of Covid-19, and if the current quarantine period determined based on hospitalized patients is optimal.