People shop in a shopping mall in Harbin, capital of northeast China's Heilongjiang province, March 29, 2020. (WANG JIANWEI / XINHUA)

BEIJING/WUHAN - China must shore up its preventive measures against the imported cases of COVID-19 as cases are soaring overseas, a health official said Monday.

Since China reported no new domestic case for the first time on March 18, there have been reports of sporadic cases in the country, said Mi Feng, a spokesperson for the National Health Commission, at a press conference in Beijing.

Mi urged solid implementation of prevention and control measures against a rebound in COVID-19 cases in the country and underscored the importance of community-level efforts.

The commission said Monday it received reports of 31 new confirmed COVID-19 cases on the Chinese mainland on Sunday, of which 30 were imported.

A new domestic case was reported in Gansu province, the commission said.

A new domestic case was reported in Gansu province, the National Health Commission said.

Also on Sunday, four deaths and 17 new suspected cases, were reported on the mainland, according to the commission. All the newly reported deaths were in Wuhan, provincial capital of Hubei province, while all the new suspected cases were imported ones.

No new confirmed cases were reported on Sunday in Wuhan, the hardest-hit city in Hubei.

The province also registered no increase in new COVID-19 cases on Sunday, according to the commission.

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On Sunday, 322 people were discharged from the hospital after recovery, while the number of severe cases decreased by 109 to 633.

As of Sunday, the mainland had reported a total of 723 imported cases, with zero deaths reported among those cases. Of the imported cases, 93 had been discharged from the hospital after recovery, and 630 were being treated in hospital with 19 in severe conditions, said the commission.

The overall confirmed cases on the mainland had reached 81,470 by the end of Sunday, including 2,396 patients who were still being treated, 75,770 patients who had been discharged after recovery, and 3,304 people who died of the disease.

The commission said that 168 people were still suspected of being infected with the virus, 165 of whom were from abroad.

The commission added that 19,235 close contacts were still under medical observation after 1,575 people were discharged on Sunday.

Hubei has so far reported a total of 67,801 confirmed COVID-19 cases, including 50,006 in Wuhan.

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Hubei saw 317 patients discharged from hospital after recovery Sunday. Among the 1,733 patients being treated in hospital, 427 were still in severe condition and another 174 in critical condition.   

By the end of Sunday, 641 confirmed cases including four deaths had been reported in the Hong Kong Special Administrative Region (SAR), 38 confirmed cases in the Macao SAR, and 306 in Taiwan including five deaths.

A total of 118 patients in Hong Kong, 10 in Macao and 39 in Taiwan had been discharged from the hospital after recovery.