Novel Coronavirus: Transmission Before Illness Documented

— German workers caught virus from Chinese colleague who showed no symptoms

Last Updated January 31, 2020
MedicalToday

The Chinese employee of a German firm who transmitted the novel coronavirus to co-workers during business meetings did so while still appearing healthy, according to clinicians and researchers in Munich.

Camilla Rothe, MD, of University Hospital LMU Munich, and colleagues reported in a rushed into online publication Thursday evening that the Chinese woman "had been well with no signs or symptoms of infection" while in Germany on Jan. 20 and 21, "but had become ill on her flight back to China" where she tested positive for the virus on Jan. 26.

The first of her German colleagues developed symptoms on Jan. 24; three others tested positive on Jan. 26. Notably, only two of the Germans came into contact with the Chinese colleague during her stay, Rothe and colleagues said; "the other two patients had contact only with Patient 1," the first to develop symptoms.

"The fact that asymptomatic persons are potential sources of 2019-nCoV infection may warrant a reassessment of transmission dynamics of the current outbreak," Rothe's group wrote.

Previously, Chinese officials said they believed asymptomatic transmission had occurred in patients there, but public health authorities elsewhere expressed skepticism. "We haven't been able to confirm by data ... transmission during the asymptomatic phase," CDC Director Robert Redfield, MD, said on Tuesday.

Although Rothe and colleagues didn't identify the company specifically, details of their narrative matched earlier media reports about four German workers developing infections after meeting with a Chinese colleague. Those reports identified the company as Webasto, a Bavarian auto parts supplier with operations in the Chinese city of Wuhan, where the coronavirus outbreak began in December.

German media that a fifth Webasto employee in Germany had been diagnosed with the infection.

Primary Source

New England Journal of Medicine

Rothe C, et al "Transmission of 2019-nCoV Infection from an Asymptomatic Contact in Germany" N Engl J Med 2020; DOI: 10.1056/NEJMc2001468.