Legal experts have lauded moves by some cities to hide sensitive personal information about people with COVID-19, including their surnames and ages, seeing it as a big step in privacy protection and suggesting it be extended across the country.

A statement posted by the Shanghai Municipal Health Commission on Friday only disclosed the places three confirmed cases had visited and what public places had potential risks. The surnames, ages, genders and hometowns of those infected, often released in previous reports, were withheld. Beijing did the same.

"It's good to see city governments focus more on the whereabouts of confirmed cases instead of detailing their personal information when releasing epidemiological investigation reports to the public," Wang Sixin, a professor specializing in internet laws and rules at Communication University of China, said on Monday.

Wang welcomed the short but clear statement, saying it not only told local residents where the risks were, but also safeguarded patients' privacy.

"Disclosing more information isn't necessarily better, as our ultimate goal is to keep more people from places of risk and strengthen preventive measures, not figure out who the infected people were and isolate them," he said.

"Protecting the privacy of confirmed cases is as significant as helping others avoid risks," he said, adding some infected people have been troubled when their personal information was disclosed.

In December, a 20-year-old female patient, the granddaughter of an elderly couple confirmed as being infected earlier in Chengdu, Sichuan province, had her personal information exposed on the internet amid claims that she had continued to travel around the city and frequent a number of public places after it was known that other members of her family were infected.

The woman's personal details, including her full name, photos, address, mobile phone number and ID number, soon appeared online.

She then began to receive phone calls and text messages from strangers that questioned her and asked why she visited many places after knowing her family members were infected.

In a public apology, she explained that she did not know her grandmother had contracted the virus, adding she felt hurt by the abusive messages she received.

"No matter whether the woman's personal information was carelessly leaked by the epidemiological investigators or sought by netizens, her normal life was disturbed," said Li Ya, a lawyer from Beijing Zhongwen Law Firm.

"How to protect the privacy of infected people while guaranteeing the public interest has always been a challenge for governments in pandemic control. So the recent change made by the big cities deserves a thumbs-up."

Infected people are also victims, so hiding their personal information can prevent them from suffering secondary damage, he added.