Dr. Anne Schuchat, principal deputy director of the Centers for Disease Control and Prevention, told a National Press Club audience on Feb. 11 that China would likely soon allow American experts into the country to help fight the coronavirus outbreak. Photo: Al Teich

American experts believe there are "a much greater number" of cases of coronavirus cases in China than the 42,000 authorities there have reported, a top official of the U.S. Centers for Disease Control said, but so far she said there has been little spread of the disease in the United States.

Speaking Feb. 11 at a Newsmakers briefing at the National Press Club, Dr. Anne Schuchat, principal deputy director of the CDC, said the under-reporting resulted from pressure to care for severely ill patients in a crisis situation and a shortage of laboratory capacity to test for the new disease.

She said drastic measures taken by the Chinese government --including travel restrictions on about 60 million people -- had probably reduced the spread of the coronavirus outside its epicenter in the city of Wuhan and Hubei province. But she said she was hopeful that Chinese authorities would soon allow American epidemiologists, virologists and infection-control experts into the country to join the effort to study and fight the epidemic.

"My understanding is that in the latest discussions there's been receptivity [by the Chinese]," she said. "We have a lot to offer."

Schuchat worked in China during the 2003 outbreak of the severe acute respiratory syndrome (SARS) virus. She has also conducted research on the Ebola outbreak in Africa and H1N1 epidemic in Asia.

The number of deaths from the coronavirus stood at slightly more than 1,000 earlier in the week, virtually all of them in China.

This puts the death rate from the disease at about 2 percent of reported cases, Schuchat said, considerably less than the 10 percent mortality rate from SARS.

But she said the current outbreak "is spreading much more quickly than SARS did." She said the new disease seems much easier to transmit, apparently through droplets in the air. But she said full understanding of the means of transmission has not yet been achieved.

So far, 13 cases of coronavirus have been confirmed in the United States -- 11 among people who had been in Wuhan and two from among their partners. Schuchat said symptoms in all of the U.S. cases have been "very mild."

She said the first group of 195 people who were evacuated from Wuhan by the U.S. State Department would be released from quarantine on Tuesday. In 14 days, she said, none had shown symptoms of the disease. Schuchat said the CDC would "relook" at the need for a 14-day quarantine period for persons who had been in a coronavirus area.

"So far our strategies seem to be working in the U.S.," Schuchat said. "But it may be with additional cases, particularly if they don't involve symptoms, it may be difficult to block the spread" of the disease. She said, if needed, spread of the disease could be slowed by having more people telework or closing schools.

Schuchat the Chinese have released genomic information on the coronavirus, which CDC scientists have used to develop a test for rapid diagnosis. Test kits are being shipped to state health departments, the U.S. military, and other countries that want them. So far, she said 464 cases of the disease have been diagnosed outside of China, and only two of those have been fatal.

In response to a question, Schuchat rejected a theory that the coronavirus may have escaped from a bio-weapons laboratory in Wuhan. She said the genomic sequence posted by the Chinese is "consistent with animal-to-human acquisition."