NEW YORK (CBSNewYork) – New York City health officials are bracing for the coronavirus outbreak to reach the five boroughs.

Five cases have been confirmed in the United States, and dozens are still being tested nationwide, including three in New York and one in New Jersey.

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All of the confirmed patients recently arrived from China, where 106 people have died.

“There is no cure at this moment. So really emphasizing to New Yorkers: it’s probably here already. That’s the sad reality,” Mayor Bill de Blasio said in an interview.

However, New York City Health Commissioner Dr. Oxiris Barbot says, “The current risk to New Yorkers is low and our preparedness is high.”

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Many people were seen wearing masks on Tuesday in Chinatown. A community health center on Canal Street was handing them out, along with hand sanitizer.

“Some people are saying that it’s not effective at all, but I would say it’s, like, better than nothing, I guess,” said Tony Wu, who was wearing a surgical mask as a precaution.

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“I think in general there’s a concern going around, especially in the Asian community,” one man said.

Tracy Ye lives in Chinatown and told CBS2’s Reena Roy she’s concerned about her two children in public school.

“If something happens in New York City… then don’t go to school,” she said.

People who return from China and develop flu-like symptoms — and those who live with them — are most at risk.

“After Chinese New Year, I think a lot of people came back from China,” Ye said.

“It’s inevitable that the Chinese community will most likely be affected first,” said Dr. Warren Chin, executive director of the Chinese American Medical Society.

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Scientists are concerned about the new disease, because it’s closely related to other viruses, like SARS, which killed nearly 800 people. Symptoms are similar to a cold or flu, including cough, fever and, in more severe cases, shortness of breath and pneumonia.

It’s believed that if you have the virus, you will have symptoms, and casual contact, like sharing public spaces, will not make it spread.

That’s why doctors say wearing a mask is only necessary for doctors treating sick patients.

Washing your hands frequently and coughing into your elbow are all things you can do to protect yourself against the coronavirus, plus the flu and common cold, which are far more common.

“We forget that the 2020 influenza has killed over 6,000 people already in the United States alone. That is our biggest problem,” said Dr. Yick Moon Lee, president of the Chinese American Medical Society.

It’s believed the outbreak started in the city of Wuhan, China, which is on lockdown.

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The U.S. State Department plans to airlift diplomats and other Americans from there as early as today, but officials say capacity is extremely limited.

Meanwhile, 1,000 Americans are reportedly stuck because of travel restrictions, including a professor from Stony Brook University.

“We are all working to arrange a flight home for him ASAP,” said Sen. Chuck Schumer.

The Centers for Disease Control and Prevention urged Americans to avoid non-essential travel to the country. Right now, 17 cities with more than 50 million people are on lockdown in the most far reaching disease control measures ever.

Health officials say despite several reported cases in the U.S., there is no evidence the virus is spreading across the country. That’s likely because security has been tight at many of the country’s major airports. On Tuesday, Newark Liberty International joined John F. Kennedy Airport in New York, San Francisco International and Los Angeles International, Chicago’s O’Hare and Atlanta’s Hartsdale to have enhanced screening for flights coming from China.

New Jersey Sens. Robert Menendez and Cory Booker released the following statement:.

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“As more cases of coronavirus spike across the globe, we must do everything we can to protect Americans here at home. That starts by ensuring all passengers traveling from the affected regions are properly and thoroughly screened upon arrival in the U.S. It is only prudent that any robust and comprehensive public health response include stepped-up efforts at each of our country’s major ports of entry—including Newark Liberty International Airport,” the senators said. “There is no question that Newark Liberty is one of the nation’s busiest airports with daily flights arriving from all over the world. We are pleased that the CDC has answered our repeated requests and included Newark Liberty in the agency’s response plan.