On San Francisco's Noriega Street, Chinese restaurants and grocery stores have seen business plummet, some say by 50 percent.
And, as CBS News Correspondent John Blackstone reports, it's the same in Chinatowns across the country because of worry about SARS, Severe Acute Respiratory Syndrome.
"People are not eating out, they're not going out to shop," says Rose Pak, spokesperson for San Francisco Chinese Chamber of Commerce.
Customers virtually fled when a note on the Internet claimed the owner of the Mong Kok Restaurant, Mabel Tang, was severely ill with SARS. But the note was a hoax, and Tang says she is healthy.
In San Francisco, there has not been one confirmed case of SARS. However, the epidemic of fear is spreading.
One business that is booming in Chinatown is selling facemasks.
"I would say I sold over 10,000 [facemasks]," says pharmacist Patrick Eng.
In New York, to combat SARS anxiety, Mayor Michael Bloomberg went for a Chinatown lunch. And in Los Angeles, a public health official turned his meal into a photo opportunity.
But as hard as it is to stop a virus, stopping fears and rumors may prove even harder.
Fact From Fiction
CBS News medical correspondent Dr. Emily Senay says SARS is actually less contagious than the flu. It's caused by a coronavirus, which doctors believe is spread through close contact with someone who has it.
Experts believe the virus is found in fluid droplets that are expelled when a person coughs or sneezes. It could also be spread through contact with an infected person's fecal matter.
The biggest SARS outbreak in Hong Kong spread through the plumbing in an apartment complex after visits from a man sick with the disease, according to health officials.
But the bottom line is unless you've come in contact with someone who has SARS the likelihood of you getting it is low.
The latest numbers from the World Health Organization are that 159 people have died from SARS and that worldwide there are nearly 3,330 reported cases of it.
Dr. Senay says the first thing you can do to protect yourself from the virus is to stay away from someone who you think may have it. It's also a good idea to maintain good personal hygiene, that means washing hands frequently and when drying yourself use disposable towels.