NEW YORK (WCBS 880) — Mayor Bill de Blasio declared a public health emergency on Tuesday and has ordered mandatory vaccinations for people who may have been exposed to the virus in parts of Williamsburg amid a growing measles outbreak.

Since September, the city said more than 250 measles cases have been confirmed in the Brooklyn neighborhood.

"We have a situation now where children are in danger. We have to take this seriously. Every one of us has to feel responsibility for the situation because measles is so contagious, can spread so quickly," de Blasio said at news conference at a Williamsburg library on Tuesday morning.

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Under the order, unvaccinated people, including children over 6 months old, who live or work within zip codes 11205, 11206, 11221 and 11249 will be required to get an MMR vaccine.

Members of the city's Health Department will check the vaccination records of any individual who may have been in contact with infected patients.

Those who have not received the vaccine or do not have evidence of immunity may be given a violation and could be fined $1,000.

New Yorkers can get vaccinated at @nycHealthy's immunization clinics: https://t.co/zfIUDgR4Sg or call @nyc311 to find a location to get vaccinated.

Read the Commissioner's Order: https://t.co/rcG4wksbkm pic.twitter.com/qja0CiyAhu — Commissioner Oxiris Barbot (@NYCHealthCommr) April 9, 2019

“There’s no question that vaccines are safe, effective and life-saving,” de Blasio said. “I urge everyone, especially those in affected areas, to get their MMR vaccines to protect their children, families and communities.”

The order will remain in effect through April 17. The city's Board of Health will then decide whether to extend or rescind the order.

EXTRA: Read the vaccination declaration (pdf)

The city's Health Department says yeshivas and day care centers will immediately be issued a violation and could be subject to closure if they let in unvaccinated students.

The mayor told NY1 on Monday: “What we’re seeing is very clear, children cannot — must not — go to school if they are not vaccinated.”

He went on to say that the school will be held responsible if an unvaccinated child attends classes there and reasserted the Health Department’s threat of fines and closure.

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Dr. Herminia Palacio, deputy mayor of Health and Human Services, also said Tuesday she wants the people in Williamsburg to understand “vaccines are safe, that they are required, that they are, in fact, much safer than getting actual disease, that this is not like some little cold thing, that people can get hospitalized, they can get pneumonia, they can get inflammation of the brain, they can die.”

She says reports of parents attending “measles parties” to intentionally expose children to the measles disease is “very dangerous” and could be potentially deadly.

“We have a clear and present danger,” the mayor said, according to the New York Post. “This is serious, serious stuff.”

A one-week surge in measles cases has sickened Americans in numbers not seen since measles was declared eliminated in 2000. Federal health officials say there have been over 460 measles cases reported throughout the country in 2019.

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The CDC says the anti-vaccine movement is partly responsible for 100 new cases last week, mostly in the Orthodox Jewish community in New York.

“As a pediatrician, I know the MMR vaccine is safe and effective. This outbreak is being fueled by a small group of anti-vaxxers in these neighborhoods. They have been spreading dangerous misinformation based on fake science,” said Health Commissioner Dr. Oxiris Barbot. “We stand with the majority of people in this community who have worked hard to protect their children and those at risk. We’ve seen a large increase in the number of people vaccinated in these neighborhoods, but as Passover approaches, we need to do all we can to ensure more people get the vaccine.”

Currently, the number of measles cases in the Brooklyn Orthodox community is up to 285, according to the Health Department. Cases are especially high in Williamsburg and Borough Park, which have so far seen 228 cases and 49 cases, respectively.

In January, one yeshiva defied the Health Department's order and allowed non-vaccinated kids back in. That yeshiva is now connected to more than 40 measles cases.

Gov. Andrew Cuomo reacted to the mayor’s announcement on WAMC radio saying it’s “legally questionable” whether the city can force people to get vaccinated if it violates their religious beliefs.

“Look it’s a serious public health concern, but it’s also a serious First Amendment issue and it is going to be a constitutional, legal question,” Cuomo said.

He questioned if society and government have the right to tell people to vaccinate their children over fears that their own child may become sickened.

He asks: “Do we have the right — does society, government have the right to say ‘you must vaccinate your child because I’m afraid your child is going to infect my child, even if you don’t want it done and even if it violates your religious beliefs?’”

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State Sen. David Carlucci is pushing legislation that would end most exemptions for vaccinations for children going to school.

“If you have a medical exemption and a doctor signs off on it, then that is totally fine. But we have to stop this practice of allowing people to opt out of the vaccination process,” Carlucci said.

As Passover approaches, there’s concern people will travel, gather together and potentially spread the virus.

Measles is a highly-contagious, airborne virus that easily spreads through coughing and sneezing. The virus can live for up to two hours in the air or on surfaces. It causes fever, runny nose, cough, red eyes and sore throat, followed by a rash.

No deaths have been reported so far, but measles can lead to pneumonia and encephalitis.

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