In the US, officials said they weren't surprised to hear about a new case among the evacuees from Wuhan, who spent 14 days at military bases, because anyone who lived or traveled in Hubei province was at high risk.
"This outbreak could still go in any direction", WHO Director-General Tedros Ghebreyesus said, the BBC reported on Thursday.
Noting that combating coronavirus is a big test for the country's governance system and governance ability, he stressed the need to strengthen areas of weakness and close loopholes exposed by the current epidemic.
Chinese health authorities said the sudden rise is due to inclusion of clinically-diagnosed cases in Hubei.
China reported 254 deaths Thursday compared with about 100 in recent days.
"The duties of medical workers at the front are indeed extremely heavy; their working and resting circumstances are limited, the psychological pressures are great and the risk of infection is high", Zeng Yixin, vice-minister of the commission, told a news conference. Of the 5,090 new cases, 3,095 fell into that category. China announced another 121 deaths Friday, bringing the total to at least 1,383, including three deaths outside mainland China.
However, the WHO's Ryan said the numbers of infected health workers is sad but not alarming. The moves followed the dismissals this week of two leaders of the provincial health commission and reports from state media about a slew of others expelled from the party for missteps related to the epidemic. Michael Ryan, executive director of the WHO's health emergencies program, said the organization is "very much engaged" with the Olympics planning - but that there has been no specific discussion yet regarding the event.
Chinese scientists are testing two antiviral drugs and preliminary results are expected in weeks, while the head of a Wuhan hospital said that plasma infusions from recovered patients had shown some encouraging preliminary results. A total of 6,723 people had been discharged from the hospital after recovery.
A Chinese train attendant and medical worker gesture to each other across the glass, as the train prepares to depart for the city of Wuhan, the epicenter of the novel coronavirus outbreak.
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Messonnier also noted that the U.S. Centers for Disease Control and Prevention has launched a new strategy aimed at stemming any potential spread of coronavirus within the United States.
Another 44 people aboard a cruise ship that has been quarantined for over a week in Japan's Yokohama harbor tested positive for coronavirus Thursday, Japanese health officials said. The ministry statement said the person was hospitalized and in isolation.