NEW ROCHELLE, N.Y. (CBSNewYork) – The number of confirmed coronavirus cases in New York has grown to 11, Gov. Andrew Cuomo said Wednesday.

Also Wednesday, Mayor Bill de Blasio said a New York City public school teacher is under self-quarantine after showing symptoms of the virus.

Nationwide, California reported its first death due to coronavirus. Eleven people have now died, ten of them in Washington state.

While Westchester County was just getting news that a 50-year-old New Rochelle man and his family tested positive for coronavirus, along with the neighbor who drove him to the hospital, there were startling development late Wednesday afternoon. Cuomo now says another friend, his wife and three children have also tested positive.

“A friend of the lawyer who spent time with and in close proximity with the a number of situation that person also tested positive. We then tested that person’s wife, two sons, and daughter, and they all tested positive,” Cuomo said.

The wife and daughter of the New Rochelle patient were asymptomatic even though they tested positive, Mayor Bill de Blasio said.

Westchester County Executive George Latimer is urging everyone to remain calm.

Watch: Gov. Andrew Cuomo, Westchester Officials Discuss Additional Coronavirus Cases In NY

“There is a spread of a contagious virus. There’s also the spread of of misinformation and the spread of fear. And we may not be able to control what happens to a virus but we can control that spread of misinformation and fear,” Latimer said.

The New Rochelle man, first in Westchester to contract the disease, is hospitalized. Under mandatory self-quarantine are his wife, a 20-year-old son who is a student at Yeshiva University in Washington Heights, and a 14-year-old daughter at SAR High School in Riverdale.

The neighbor, the friend and now his family are also required to stay in their home for 14 days.

“For the people that have tested positive for coronavirus that you have asked to self-quarantine, how is that being policed?” asked CBS2’s Hazel Sanchez.

“That is a mandatory quarantine situation,” Cuomo said.

“So that’s basically on the honor system?” Sanchez asked.

“No, no, no. That is policed. That is monitored and that is policed. We check on those people and make sure they are doing it,” Cuomo said.

CORONAVIRUS OUTBREAK

The Westchester County Health Department says its staff is coordinating with the state to make sure people infected don’t violate the mandatory quarantine.

“We do reach out to people it depends on their situation and what we’ve asked them to do. We may be calling or Skyping them. It depends on the level of security that’s required,” said Westchester County Health Commissioner Sherlita Amler.

As a precaution, SAR High School will be closed until March 10. SAR Academy, Yeshiva University and Young Israel of New Rochelle will be closed until Friday.

Students and members of the synagogue are being asked to self-quarantine through Friday.

Schools in the Hastings on Hudson District will close Thursday and Friday to sanitize all of the buildings. All school activities will be canceled on Monday, March 9. CBS2 has been told they’re doing this out of an abundance of caution.

Mount Vernon City School District announced they are also closing all school buildings and offices for cleaning and disinfecting after learning two students have been quarantined for possible exposure to coronavirus.

“It is an imperfect science. Especially when you have a situation like this one. Or you have a person that may have contacted so many people. But you do the best you can again, trying to contain, trying to contain,” Cuomo said.

The governor says the Manhattan health care worker, first to test positive for coronavirus, is recovering well at home. Her husband tested negative. Though his test results are negative, city officials say they are treating him as a positive result, and are requiring quarantine.

De Blasio said disease detectives had identified two people – a roommate and a close friend – that warrant testing for coronavirus at Yeshiva University. Results of those tests are pending at Bellevue Hospital.

The infected man, believed to have gotten coronavirus through community spread, was in severe condition on Wednesday morning and is the first person in the New York area to be hospitalized due to the disease.

“He has an underlying respiratory illness. So when we talk about the vulnerable population here – senior citizens, immune compromised, or an existing underlying illness, especially an underlying respiratory illness because this is a respiratory disease – this gentleman fits in that category,” Cuomo said.

Cuomo said that 80% of people who get the virus will “self resolve,” and the remaining 20% may need medical intervention. The lethality rate of coronavirus, he said, was around 1.4%, roughly double the flu rate.

“We have an epidemic caused by coronavirus. But we have a pandemic that is caused by fear,” Cuomo said. “I think in this case people are suspect about what they’re hearing because government now is so polarized in so many ways, the environment is so political, that you hear different messages about this situation. And then it gets politicized.”

Cuomo said he expects the number of confirmed cases will continue to grow.

“If you understand the facts, there is no reason for undue anxiety,” Cuomo said. “There are going to be dozens and dozens and dozens of people. And the more people you test, the more people you’re going to find.”

Watch: Mayor Bill de Blasio, NYC Officials Update On Coronavirus

Cuomo also said that CUNY and SUNY students who were participating in study abroad programs in China, Italy, Japan, Iran and South Korea were being recalled. They’ll return on a chartered plane and be quarantined in dormitories for 14 days, Cuomo said.

The New Rochelle man works as an attorney at Lewis and Garbuz, P.C. in Manhattan. He’s a member of Young Israel of New Rochelle, which will be closed through March 8. Five hundred to 700 people who attended services there on Feb. 22 and 23 have been told to self-quarantine through Sunday. Westchester County Executive George Latimer announced a hotline for those who had attended the Young Israel events with that patient: 1-866-588-0195.

“This is a very emotionally trying time for us all. When we first heard of the coronavirus it seemed so remote. It has now come not only to our doorstep, but has pierced our lives. Clearly, this entire episode is frightening and difficult, but let us not lose sight, however, that we are following the procedures mandated by our state’s health department to try to prevent the spread of this virus. That is a sacred obligation that we all must take very seriously,” Rabbi Reuven Fink of Young Israel of New Rochelle wrote on Facebook.

Officials are also monitoring seven employees at the law firm and an intern there. They are all undergoing testing. Five are being tested in New York City and one in New Jersey. The remaining two are also being tested.

The Lawrence Hospital, which is the first hospital that the lawyer went to, is having eight employees tested, Cuomo said.

The NYPD says five officers who recently traveled to affected areas are also self-quarantined.

The Department of Consumer Worker Protection has formally declared that there is a shortage of face masks in New York City, which means they can now fine stores if they’re price gouging. Anyone who believes a store is price gouging is urged to call 311.

Meanwhile, on Long Island, Nassau County officials want residents to know they are preparing for the coronavirus outbreak, including working on getting local testing.

Watch: Nassau County Officials Preparing For Coronavirus Outbreak —

“The ability to test locally, I think, would help speed up the process and also be very reassuring to our residents,” Nassau County Executive Laura Curran said.

“We feel we’re as prepared as we can be, and we’re ready to manage those individuals who may come into the hospital or help wherever we can,” NuHealth Board Chariman Robert Detor said.

There are no confirmed cases in Nassau County.