Distrust and suspicion toward mainlanders, already deepened by months of prodemocracy protests sparked by fears of Beijing overreach, have grown. The Society for Community Organization, a local human-rights group, said last week that it had identified more than 100 restaurants where owners refused to serve Mandarin speakers and nonlocals (Hong Kong’s native language is Cantonese).

Minnie Li, a sociology lecturer at the Education University of Hong Kong who was born in Shanghai, reached out to the owner of Kwong Wing Catering, a popular restaurant chain that has aligned itself with the prodemocracy movement and said it will not serve Mandarin speakers, to try to discuss the company’s position. Though she was unable to secure a meeting with the chain’s owner, she and a small group of Mandarin-speaking friends visited two of its restaurants and brought along face masks, to donate, as well as a collection of articles written by Mandarin speakers who support the prodemocracy movement. But the outreach efforts were largely a disappointment, she said. Kwong Wing Catering did not respond to a request for comment. The chain’s position was rebuked by the government’s Equal Opportunities Commission.

“To associate a disease with a group of people and believe that banishing, quarantining, and segregating members of this group would be a sound protective measure will only distract us from the real threat,” Li wrote in a series of Facebook posts about her experiences. “The lived experiences of those who are scorned, feared, driven away, and unfairly labeled as ‘infected’ may show us how the climate of fear we have created could in fact cause far more serious damage to society than the epidemic itself.” Her writings garnered widespread attention, but “the negative comments outweighed the positive ones,” she told us. People disagreed with her tactics, saying she was trying to start trouble. Others accused her of being a “colonist from China.” The comments were particularly pointed given that Li is an active and well-known participant in the pro-democracy movement. During protests last summer, she took part in a hunger strike, eventually collapsing and being rushed to the hospital. Even people who participated in the strike alongside her, she said, chastised her for confronting the restaurant.

Roger Chung, Li’s husband and an assistant public-health professor at the Chinese University of Hong Kong, described the chain as taking a consequentialist approach that ignored important, difficult questions. “In public health, we talk about the ethics behind the measure; it is not enough just to talk about the measure,” he told us. “What about the rights of people? Are you upholding any virtues and values? There are other things that we need to think about.”

The latest effort to curb the virus’s spread has come from the U.S., where President Trump announced a month-long ban on travelers from more than two dozen European countries, excluding the United Kingdom, in an effort to “keep new cases from entering our shores.”