A staff member conducts disinfection at a hospital in Urumqi, northwest China's Xinjiang Uygur autonomous region, July 21, 2020. (SONG YANHUA / XINHUA)

BEIJING / WUHAN - Central China's Hubei province, once hard hit by COVID-19, had no COVID-19 patients or asymptomatic carriers undergoing treatment or quarantine by Thursday, the provincial health commission said Friday.

Hubei cleared asymptomatic COVID-19 cases on June 30 as the final asymptomatic case was released from quarantine in the city of Ezhou

The commission said the province's last asymptomatic case was discharged from medical observation on Thursday. Previous reports indicated that the case was in Enshi Tujia and Miao Autonomous Prefecture.

No newly confirmed, asymptomatic or suspected cases of COVID-19 were reported in Hubei Thursday, the commission said.

By Thursday, four close contacts were still under medical observation.

Hubei cleared asymptomatic COVID-19 cases on June 30 as the final asymptomatic case was released from quarantine in the city of Ezhou.

However, three asymptomatic cases, including two arriving from overseas, were reported on July 3, and another new asymptomatic case was reported on July 7.

Hubei had reported a total of 68,135 confirmed COVID-19 cases, and 63,623 cases had been cured and discharged from hospital. The disease has claimed 4,512 lives in the province.

21 confirmed infections 

Chinese health authority said Friday that it received reports of 21 new confirmed COVID-19 cases on the Chinese mainland Thursday, 15 of which were domestically transmitted.

Of the domestically transmitted cases, 13 were reported in Xinjiang Uygur Autonomous Region and two were in Liaoning Province, the National Health Commission said in its daily report.

No deaths related to the disease were reported Thursday, the commission said.

As of Thursday, the overall confirmed cases on the mainland had reached 83,750, with 243 patients who were still being treated and 12 in severe condition

On Thursday, 18 COVID-19 patients were discharged from hospitals after recovery, and one new suspected case was reported.

As of Thursday, the overall confirmed cases on the mainland had reached 83,750, including 243 patients who were still being treated, with 12 in severe condition.

Altogether 78,873 people had been discharged after recovery, and 4,634 had died of the disease, the commission said.

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Six new imported cases were reported on Thursday, of which five were reported in Guangdong province, and one in Shanghai.

 By the end of Thursday, a total of 2,029 imported cases had been reported on the mainland. Of the cases, 1,951 had been discharged from hospitals after recovery, and 78 remained hospitalized with two in severe condition. No deaths from the imported cases had been reported.

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There were still two suspected COVID-19 cases, the commission said.

According to the commission, 7,526 close contacts were still under medical observation after 66 people were discharged from medical observation Thursday.

Also on Thursday, 43 new asymptomatic cases, including nine from outside the mainland, were reported and 11 asymptomatic cases were re-categorized as confirmed cases.

The commission said 204 asymptomatic cases, including 96 from outside the mainland, were still under medical observation.