Like so many shops and restaurants in Boston's Chinatown, Jade Garden has seen its sales fall off a cliff over the past couple of weeks. Peter Cao, who runs the restaurant with his family, blames what many others do: fear and rumors related to the new coronavirus currently roiling China and other parts of Asia.

"Never seen it before," Cao said. He said that sales have decreased by about 50% in recent days, and that business hasn't felt this slow since the blizzards of 2015.

That sentiment was echoed by Boston Mayor Marty Walsh, who hosted a news conference and lunch at the restaurant on Tuesday in an effort to show support for Chinatown businesses. The dramatic decrease in foot traffic that business owners are reporting exceeds anything he's seen during his time in office, Walsh said.

During the midday event, at which journalists outnumbered the patrons, the mayor called on the public not to give into fear or bigotry.

"The people that are out there saying on social media, being racist towards the Chinatown community and Chinese people in general, I'm asking you to stop," he said. "Enough with that hate mongering. We're better than that."

"It really means a lot to Chinatown," said Cao, "because it's not just one restaurant. It's just the whole area. The whole Chinatown business went down dramatically."

The event came a day after officials for the Tokyo Marathon decided to restrict this year's race to elite runners after new cases of infection had been confirmed within Japan.

Asked whether the outbreak would have any impact on April's Boston Marathon, Walsh said that, at the moment, changing the race is unnecessary, since only one case of the coronavirus has been confirmed in the state.

The lunch came a few days after a "dim sum brunch" organized by Boston City Councilor Michelle Wu and Quincy City Council President Nina Liang. About 400 people came to the Saturday event.

As of Tuesday, the World Health Organization (WHO) reported 73,332 confirmed cases of coronavirus globally, with 99% of those cases occurring in China. Additionally, of the 1,873 deaths linked to the virus, 99.8% of them occurred within China.

"I think we have to be very careful about overreacting to a situation that isn't there," Walsh said. "If the roles were reversed" and hundreds of people in the U.S. were coming down with the coronavirus, "that's a different conversation."