Central China's Henan province reported a local confirmed COVID-19 case on Saturday, a statement released by Henan Provincial Health Commission said on Sunday.
The patient surnamed Wang, 59, a cleaner in a library in Luohe, was the only domestic confirmed case in Chinese mainland on Saturday.
Wang began to have headache on March 24 and went to see doctor at a local hospital when she started feeling feverish on Thursday night and was later isolated for treatment and further medical observation.
Wang was confirmed to be a COVID-19 patient on Saturday when her nucleic acid test came out positive.
According to the statement, Wang once traveled to Pingdingshan city by bus on March 21 and she later went to Jiaxian county to sweep the tombs in a private car driven by her friend surnamed Zhang, who is a doctor at Jiaxian County People's Hospital.
Wang had dinners with Zhang three times during the period.
Previously Zhang had a dinner with colleagues surnamed Zhou and Liu from the hospital in a local restaurant on March 13. Liu visited Wuhan earlier this year and was released from quarantine after being isolated for two weeks when Liu showed no symptoms earlier this month.
On March 25, Zhang, Liu, and Zhou were detected to be asymptomatic novel coronavirus carriers in a health examination organized by the hospital for its medical staff members.
A total of 15 people who had close contact with Wang and another 53 who once had close contacts with Liu, Zhang and Zhou have been isolated for further medical observation.