Coronavirus Spread in China Mostly Among Families, WHO Says

(Bloomberg) -- Transmission of the coronavirus in China has largely occurred within families, according to a new report that suggests the disease is spreading less readily than some experts had feared.

Of about 344 clusters of infection in Guangdong and Sichuan provinces, up to 85% occurred in households, according to the report from a team of experts convened by the World Health Organization. Further studies of family spread are underway, it said.

The agency’s report supports earlier suggestions that aggressive control measures like social distancing and China’s massive quarantine of some 50 million people can help keep the virus in check. Outside Hubei province, the center of the epidemic, the report noted a low level of community transmission -- spread that can’t be traced back to people already known to have the disease.

The team of 25 virologists, epidemiologists and other experts from countries including Germany, Japan, the U.S. and China is studying the outbreak in an effort to understand how the disease is transmitted, how dangerous it is and how to stop it. The officials recently entered Wuhan in Hubei, where they began collecting data.

China has “meticulous case and contact identification for Covid-19,” the disease caused by the coronavirus, according to the report. More than 1,800 teams of health workers are tracing tens of thousands of contacts a day in Wuhan, with “painstaking” follow-up, the report said.

Chinese health officials traced thousands of people who had been in contact with virus patients in three regions. Rates of infection among the contacts ranged from 0.9% to 4.8%.

The disease has also spread in health-care settings and prisons, the report said. However, they don’t appear to be major drivers of the overall epidemic.

Just two months after it emerged in Wuhan, the virus has spread to more than 40 counties, infecting about 80,000 people. The outbreak is roiling markets around the world as travel has been curtailed, public events canceled and regions of China and Italy locked down to minimize spread.

--With assistance from Michelle Fay Cortez.

To contact the reporter on this story: John Lauerman in London at jlauerman@bloomberg.net

To contact the editors responsible for this story: Eric Pfanner at epfanner1@bloomberg.net, James Paton

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