The mayor of New York has been forced to declare a public health emergency, as the city is in the midst of the worst measles outbreak in decades.
People who have not received the appropriate vaccinations have been warned to do so, or face a fine of up to $1,000.
Two hundred and eighty five measles cases have been confirmed since October 2018. In comparison, there were only two cases in the whole of 2017.
The outbreak has been partly blamed on an anonymous anti-vaccination pamphlet that was distributed among certain communities around New York.