A Shanghai health official on Friday urged citizens to avoid social gatherings, citing that it is one of the major causes of the spread of novel coronavirus in the city.

As of Friday noon, 269 people in Shanghai have been infected with the virus, among which 45 cases were caused by social gatherings, said Zheng Jin, a spokesperson of the municipal health commission, at the daily news conference regarding the novel coronavirus outbreak.

"We urge citizens to avoid going out, to cancel family gatherings and to urge relatives in other provinces to refrain from coming to Shanghai during this period of time," she said, adding the people can call the 12345 or 12320 hotlines to report suspected cases of infection.

Zheng also revealed locations in the city where novel coronavirus cases have been identified. The locations include a number of residential neighborhoods and metro stations in 11 of the 16 districts in the city.

Liu Ping, a senior inspector at the municipal justice department, said mediators have in the past two weeks settled about 4,000 disputes related to issues such as quarrels caused by a family member who insisted on going out or not wearing a mask and people not being cooperative when told to seek medical treatment.

"The public must stick to the laws and disease control measures, and those who conceal information, refuse quarantine or sneak off and cause problems will be investigated for endangering public safety," he said.

Earlier today, the municipal people's congress announced that people who are dishonest in their declaration of medical condition, travel history and contact with those infected with the virus, as well as those who escape medical observation, will be blacklisted in the social credit system.