SHANGHAI/BEIJING -- Mainland China reported 573 new coronavirus infections on Feb. 29, up from 427 the previous day, for the highest daily increase in a week, national health authorities said on Sunday.

The new cases were concentrated in the central city of Wuhan, where the virus emerged late last year, with 565 infections, or nearly 99% of Saturday’s total.

The death toll of 35 was February’s second lowest daily total and was down from 47 the previous day. The tally of deaths in mainland China is now 2,870, the National Health Commission said.

Of the deaths, 34 were in the province of Hubei, whose capital is Wuhan and the epicenter of the outbreak. Hubei accounted for 570 of the new cases.

The three new cases outside Hubei are the lowest number since the National Health Commission began tracking daily figures on Jan. 20.

A total of 41,625 patients have been discharged, the commission said, or 52% of total mainland infections, though officials have warned that some could again develop symptoms.

To cushion the economic impact of the epidemic, China has ordered districts to be classified into “high-risk”, “medium-risk” and “low-risk”, with the latter expected to end traffic curbs and let everyone resume work.

On Saturday, Hubei said 11 of its 103 counties had reported no new cases for at least 14 days, meeting the “low-risk” criteria. But as many as 58 of its counties are still deemed “high-risk”.

Despite some positive changes, the situation was still at a critical stage, and Hubei could not yet ease curbs on outbound travel, Ying Yong, the provincial general secretary of the ruling Communist Party, said on Saturday.

China will take steps to bring back citizens from high-risk countries if necessary, foreign ministry official Cui Aiming told reporters on Sunday, adding that it has arranged 10 flights to bring home 1,314 so far, but he did not name any countries.

China needs to take a “long-term view” of the outbreak and plug “loopholes” in its laws and emergency response mechanisms, President Xi Jinping said in speeches published in the Communist Party’s theoretical journal, Qiushi (Seeking Truth) on Sunday.

China must set up an emergency reserve and supply system to ensure vital materials are deployed at critical times, he added.

As many as 53 countries have reported cases, the World Health Organization said on Saturday, with Mexico and San Marino the latest additions. In a bulletin, it said there were 6,009 cases outside China, an increase of 1,318 from the previous day.

China has refrained from blanket travel bans, but some local governments, such as in Beijing, have ordered self-quarantine for travelers from countries where the virus has spread.