All of the reported deaths from the outbreak have been in China, but Travelers have spread the virus to numerous other countries. Cases have been confirmed in Australia, Malaysia, Nepal, Vietnam, Singapore, Japan, South Korea, Taiwan, Thailand, France and the United States.
People without symptoms could be spreading the virus, researchers say.
The medical journal The Lancet published a study on Friday suggesting that people infected with the coronavirus might be able to spread it even if they do not have flu symptoms.
Researchers studied a family of seven in the Chinese city of Shenzhen, five of whom had traveled to Wuhan, the center of the outbreak. Two of them came into contact with an infected relative in a hospital there. Testing conducted days later, after they flew home, found that six members of the family had the coronavirus, including one who had not gone to Wuhan.
One infected family member, a child, had no symptoms, suggesting that people with the virus might be spreading it without knowing that they have it, the study found.
“It shows this new coronavirus is able to transfer between person to person, in a hospital setting, a family home setting, and also in an inter-city setting,” Yuen Kwok-yung, an author of the study , said in an interview. “This is exactly what makes this new disease difficult to control.” Dr. Yuen characterized the disease as “asymptomatic walking pneumonia.”