Patrons keep a distance from each other as they line up in front of a dessert shop in Wuhan, central China's Hubei province, April 8, 2020. (XIAO YIJIU / XINHUA)

BEIJING/WUHAN - A total of 280 local cases of asymptomatic coronavirus infections have been reported by 17 provincial-level regions in China since April 1, a health official said Thursday.

The detection, reporting and management of such cases must be stepped up following relevant regulations, Mi Feng, a spokesman of the National Health Commission, said at a press conference in Beijing.

Noting an increase in imported cases, Mi urged strict monitoring and quarantine measures for inbound passengers.

The commission said earlier on Thursday it received reports of 63 new confirmed COVID-19 cases on the Chinese mainland Wednesday, of which 61 were imported.

Two new domestic cases were reported in Guangdong province, the National Health Commission said.

Two deaths were reported in Hubei province on Wednesday. A total of 17 new suspected cases - 16 imported ones and one in Heilongjiang province - were reported on the mainland.

As of Wednesday, the mainland had reported a total of 1,103 imported cases

According to the commission, 91 people were discharged from hospitals after recovery, while the number of severe cases decreased by 13 to 176.

As of Wednesday, the mainland had reported a total of 1,103 imported cases. Of those cases, 374 had been discharged from hospitals after recovery, and 729 were being treated with 31 in severe condition, said the commission.

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The overall confirmed cases on the mainland had reached 81,865 by Wednesday, including 1,160 patients who were still being treated, 77,370 people who had been discharged after recovery, and 3,335 people who died of the disease.

The commission said that 73 people were still suspected of being infected with the virus.

It added that 12,510 close contacts were still under medical observation. On Wednesday, 1,848 people were released from medical observation.

Also on Wednesday, 56 new asymptomatic COVID-19 cases, including 28 ones from abroad, were reported on the mainland. A total of 15 asymptomatic cases, all imported, were re-categorized as confirmed infections, and 32 were discharged from medical observation including seven imported cases, according to the commission.

Hubei saw zero new confirmed cases and two deaths on Wednesday, according to the provincial health commission

The commission said 1,104 asymptomatic cases, including 364 from abroad, were still under medical observation.

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No new confirmed cases were reported Wednesday in Hubei, the provincial health commission said Thursday, adding that there were two more deaths.

The commission said Hubei had 674 asymptomatic patients under medical observation by Wednesday, after 20 cases were ruled out while 24 new patients were reported.

Forty-five COVID-19 patients were discharged from hospitals after recovery Wednesday. Among the 401 patients being treated in hospital, 70 were still in severe condition and 67 others in critical condition.

Hubei has so far reported 67,803 confirmed COVID-19 cases in total, including 50,008 in Wuhan.  

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By Wednesday, 960 confirmed cases including four deaths had been reported in the Hong Kong Special Administrative Region (SAR), 45 confirmed cases in the Macao SAR, and 379 in Taiwan including five deaths.

A total of 264 patients in Hong Kong, 10 in Macao and 67 in Taiwan had been discharged from hospitals after recovery.