The number of confirmed infections of the novel coronavirus on the Chinese mainland climbed to 31,161 as of Thursday midnight, including 636 deaths, according to the National Health Commission.

Among them, 3,143 confirmed cases and 73 deaths were newly reported on Thursday, the commission said. 

A total of 4,833 suspected cases were reported on Thursday, bringing the total number of suspected cases on the Chinese mainland to 26,359 as of Thursday at midnight, the commission said on Friday.

The number of confirmed cases rose to 24 in Hong Kong, including one death, 10 in Macao and 16 in Taiwan, the commission said.

Health authorities on the mainland have traced 314,028 people with close contact with patients, with 186,045 of them still under medical observation, according to the commission.

A total of 1,540 people have been discharged from the hospital on the mainland as of Thursday midnight, the commission said.

Hubei province, center of the outbreak, reported 2,447 new confirmed cases and 69 new deaths on Thursday, bringing the two numbers up to 22,112 and 618 respectively according to the province's health commission.

Xiaogan city of Hubei province became the second city with more than 2,000 confirmed cases besides Wuhan (11,618 confirmed cases by Thursday midnight). Xiaogan reported 255 new confirmed cases on Thursday, bringing the total number of the city to 2,141, according to the provincial health commission. 

A total of 15,804 people sickened by the virus are still hospitalized in the province. Among them, 3,161 people have serious symptoms and 841 are in critical condition, the commission said.

Medical observation continues on 64,057 people.