SHANGHAI, March 20 ― China's first local coronavirus case since February was a staff worker at a hospital and had received two shots of a vaccine between end-January and early February, state media reported today.

The patient, identified by her surname Liu, had been working in the quarantine area of a hospital in Xian city since March 4, and was mainly responsible for collecting samples of quarantined people for coronavirus testing, reported the Health Times.

The Health Times is listed as a newspaper published under The People's Daily, the official newspaper of China's ruling Communist Party.

China had reported the case on Thursday, making it the country's first locally transmitted case since February 14.

The Health Times, citing a joint expert group of Shaanxi province where Xian city is located, said Liu was infected after being accidentally exposed while in the hospital's quarantine area.

The publication quoted Zeng Guang, former chief epidemiologist of China's Center for Disease Control and Prevention, as saying that the protection rate of the vaccine is "not 100 per cent”, and that it is "relatively safe rather than "absolutely safe”, but the public should not doubt domestic vaccines due to this case.

"The efficacy rate of domestic vaccines in preventing severe cases in China is more than 90 per cent, and the overall protection rate is more than 70 per cent,” said Zeng, adding that coronavirus treatment hospitals are high-risk areas where vaccinated medical staff cannot rule out the possibility of infection.

Thirty-three staff working in the quarantine area with Liu had negative nucleic acid test results, and have undergone centralised medical isolation and observation.

The Health Times did not specify which vaccine Liu had received.

China currently has four domestic Covid-19 vaccines for public use, with vaccines made by CanSino Biologics Inc (CanSinoBIO) and Wuhan Institute of Biological Products, an affiliate of China National Pharmaceutical Group (Sinopharm), receiving approval in February.

They join a vaccine from Sinovac Biotech, also approved last month, and another from Sinopharm's Beijing unit approved last year.

A fifth vaccine, developed by the Institute of Microbiology of Chinese Academy of Sciences (IMCAS), was also approved for emergency use in China, the institute announced on March 15. ― Reuters