Staff members check residents' health QR code at the entrance of Chucai community in the Wuchang district of Wuhan, central China's Hubei province, April 15, 2020. (LI HE / XINHUA)

BEIJING/WUHAN/HARBIN - A Chinese health official Thursday called for strengthened health monitoring of inbound travelers as all 12 new indigenous COVID-19 infections were infected by imported cases.

Efforts should be made to prevent cluster COVID-19 epidemic rebound, said Mi Feng, spokesperson for the National Health Commission at a press conference.

Mi also said that the number of domestic severe COVID-19 patients had dropped below 50.

The commission said Thursday that it received reports of 46 new confirmed COVID-19 cases on the mainland Wednesday, of which 34 were imported.

Zero deaths were reported Wednesday on the mainland, the National Health Commission said in a daily report.

Among the new imported cases, 16 of them were in Heilongjiang province, who are all Chinese nationals returning from Russia. Of them, two were previously asymptomatic cases, according to the province's health authorities.

Among the 34 new imported cases, 16 of them were in Heilongjiang province, who are all Chinese nationals returning from Russia

Besides the 34 imported cases, the other 12 new cases were domestically transmitted, the commission said in a daily report, adding that five were reported in Guangdong province, four in Heilongjiang and three in Beijing.

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Four new suspected cases were also reported, with three of them imported in Shanghai and one domestic case in Beijing

According to the commission, 76 people were discharged from hospitals after recovery Wednesday, while the number of severe cases decreased by 18 to 95.

As of Wednesday, the mainland had reported a total of 1,534 imported cases. Of the cases, 636 had been discharged from hospitals after recovery, and 898 patients, 46 of whom were in severe conditions, were being treated, said the commission.

No deaths from the imported cases had been reported, it added.

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The overall confirmed cases on the mainland had reached 82,341 by Wednesday, including 1,107 patients who were still being treated, and 77,892 people who had been discharged after recovery, the commission said.

Altogether 3,342 people had died of the disease, it added.

As of Wednesday, the mainland had reported a total of 1,534 imported cases

The commission said that 63 people, including 61 from abroad, were still suspected of being infected with the virus.

It added that 8,484 close contacts were still under medical observation. On Wednesday, 521 people were released from medical observation.

Also on Wednesday, 64 new asymptomatic cases, including three from abroad, were reported on the mainland. Six asymptomatic cases, two of which were imported, were re-categorized as confirmed cases, and 49 were released from medical observation including 12 imported cases, according to the commission.

The commission said 1,032 asymptomatic cases, including 217 from abroad, were still under medical observation.

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By Wednesday, Heilongjiang had reported a total of 356 confirmed imported COVID-19 cases. It had traced 2,089 close contacts, with 1,336 still under medical observation.

The province reported a new imported asymptomatic case on Wednesday, bringing the total number of imported asymptomatic cases in the province to 50.

In Hubei province, the total confirmed cases remained at 67,803, including 50,008 in the provincial capital of Wuhan by Wednesday, according to local health authorities.

The provincial health commission said Hubei had 620 asymptomatic cases under medical observation by Wednesday, adding that 37 such cases were reported on Wednesday.

A total of 33 COVID-19 patients were discharged from hospital after recovery on Wednesday. All of them were from the city of Wuhan. Among the 146 patients being treated in hospital, 18 were still in severe condition and 20 others in critical condition.

Separately, 1,016 confirmed cases including four deaths had been reported in the Hong Kong Special Administrative Region (SAR) by Wednesday, while there are now 45 confirmed cases in the Macao SAR, and 395 cases in Taiwan including six deaths.

A total of 459 patients in Hong Kong, 16 in Macao and 137 in Taiwan had been discharged from hospitals after recovery.