In light of a growing crisis, New York City Health Commissioner Oxiris Barbot warned against parents throwing “measles parties” to purposefully infect their children. “Back in the day people were having parties to expose their kids to chicken pox,” said Barbot. “We live in a different world now ... there are serious consequences to that.” Measles parties are dangerous and can lead to serious illness—and even death—for infected children. Barbot’s statement came in light of Mayor Bill de Blasio declaring the city’s measles epidemic a public health emergency, issuing an order requiring people who live, work, or study in and around an Orthodox Jewish enclave in Williamsburg, Brooklyn, to be vaccinated or provide proof that they’ve developed immunity from having measles before and developed antibodies. Those who don’t meet the conditions could face fines up to $1,000.