Evidence of SARS-CoV-2 Infection in Returning Travelers from Wuhan, China
February 18, 2020 DOI: 10.1056/NEJMc2001899
As the number of cases of infection with the novel coronavirus (SARS-CoV-2) has continued to increase, many countries have established restrictions regarding travelers who have recently visited China.1 With lockdown measures imposed in Hubei Province, China,2 and a public health emergency of international concern declared by the World Health Organization,3 foreign nationals have sought to return to their home countries from China, and public health authorities are racing to contain the spread of Covid-19 (the disease caused by SARS-CoV-2 infection) around the world. This process is complicated by epidemiologic uncertainty regarding possible transmission of the virus by asymptomatically or subclinically symptomatic infected persons. It is unclear whether persons who show no signs or symptoms of respiratory infection shed SARS-CoV-2.
In this context, a group of predominantly German nationals who had stayed in Hubei Province was evacuated to Frankfurt, Germany, on February 1, 2020. They were to be transferred to Germersheim, Germany, and quarantined for 14 days, since this period is thought to be the upper limit of the incubation period of SARS-CoV-2. Screening for symptoms and clinical signs of infection was performed before their departure from China. A total of 126 travelers were allowed to board an aircraft operated by the German air force (Figure 1).