A team of medical professionals at a hospital in Wuhan says that around 40 percent of the patients with the new coronavirus they have treated may have contracted the illness at their hospital.
The team works at a Wuhan University hospital in the Chinese city at the heart of the outbreak.
They published their findings in the Journal of the American Medical Association on Friday.
The study says 138 cases were confirmed at the hospital between January 1 and 28. Of those, 41 percent, or 57 people, were medical staff or patients who were initially hospitalized for other reasons.
The study found that one patient in the surgical department may have infected more than 10 members of hospital staff.
It says that while patients had symptoms such as high fever and sense of fatigue, researchers revealed that 10 percent either had atypical symptoms such as diarrhea, or complained of nausea.
It concludes that it was difficult to screen patients with symptoms not previously associated with the virus. The team says that an important feature of the new coronavirus is the rapid human-to-human transmission among people in close contact.