When a stranger told Jeongock Choe to "go back to China" Thursday as she shopped for vegetables, she said that she started to shiver and cry, then decided to fight back.

The pregnant Choe was wearing a medical mask while shopping at a downtown Vancouver grocery store when a stranger shopping beside her made the racist comment out of nowhere, she said.

"I started shivering and I started crying because I never, ever thought that would happen to me in Vancouver after living here 10 years," said Choe.

Choe believes she was targeted, as some other Asian-Canadians have been, in the wake of the global coronavirus outbreak which originated in Wuhan, China.

She's convinced the mask she was wearing also made her a target.

Store employees in Greater Victoria say face masks and hand sanitizer are disappearing seconds after being stocked. (Tyson Koschik/CBC)

Health historians and experts say fear of the novel coronavirus is elevating some of the darker human emotions, such as xenophobia, suspicion and fear of shortages.

Infectious disease specialist Dr. Abdu Sharkawy of the University of Toronto and other experts urge people to stay calm and stop stocking up on medical-grade N95 mask supplies needed by health-care providers. He says mask-wearing in malls and airports is "perpetuating even more fear and suspicion of others."

Choe says she was wearing the mask for protection. She didn't expect to be attacked.

After the "go back to China" comment, she says she tapped the stranger who said it on the shoulder, and was accused of "slapping" her. So Choe took pictures of the woman, who shielded her face with a yellow shopping bag.

Onlookers came to Choe's defence, and she says that made her feel less alone. But she wants people to understand that, because she is 26 weeks pregnant, she wears a face mask to avoid getting sick.

A woman wearing a protective face mask uses her mobile phone while riding a train in Shanghai on February 20, 2020. (Noel Celis/AFP via Getty Images)

"It's not about we are sick, but we want to walk around to spread our virus. It's not like that. People should know better and not being judgmental," said Choe.

After 10 years in Vancouver, she said she's never experienced a racial slur like the one directed at her as she selected mushrooms.

Vancouver police confirmed they are investigating the "unfortunate incident." There have been no arrests.

The Chinese Canadian National Council for Social Justice launched its "Stop the Spread" campaign at Nathan Philips Square in Toronto on Tuesday, aimed at combating racism related to the coronavirus. Volunteers at the event wore hazmat suits with the message "Stop the Spread of racism."

Growing number of incidents

A growing number of people worldwide are deciding to fight back by posting on social media if they are attacked for their origin, race or decision to wear a mask.

Tiffany Sung of Vancouver called out a couple who baited her in Montreal on Thursday night. Sung had to cancel a recent trip to Taipei, Taiwan, because of the coronavirus outbreak.

So she and her friend headed to Quebec instead.

Last night on their way to a pub in Old Montreal the two women noticed somebody knocking "aggressively" on a restaurant window as they passed.

"They were knocking and signalling to the text on the window," said Sung. At first she didn't realize what was happening, then she read the text.

Tiffany Sung was walking by this restaurant in Montreal on March 2 when two strangers began knocking furiously on the window, pointing to this sign. Sung says she feels she was singled out because she is Asian. (Tiffany Sung/Facebook)

In white marker somebody had scrawled: 'No Corona Virus Here!'

"I was kind of immediately furious," she said. "I told him loud and clear that the writing is totally inappropriate and he was being racist by singling me out."

Things escalated and Sung left as she thought the pair were drunk and the conflict could turn dangerous.

"I kind of suspected this exists everywhere. On a walking tour of the city our tour guide said go to Chinatown and support the businesses, because they are really suffering and you know why. [Coronavirus] was just implied." she said.

Sung is considering making public her Facebook post of the Montreal couple to shame them.

She said the scrawled insult on the window was soon erased, but the fact she was singled out for simply walking past is a memory seared into her mind.