The number of confirmed measles cases in the Hudson Valley more than doubled in a few days.

Health officials from Rockland County confirmed there are now 33 cases of measles with at least five others who likely have the virus, according to NBC. Hudson Valley Post recently reported there were 11 confirmed cases.

Symptoms include a fever, rash, cough, conjunctivitis or a runny nose. Symptoms usually appear 10-12 days after exposure but may appear as early as 7 days and as late as 21 days after exposure.

Measles is a highly contagious respiratory disease caused by a virus that is spread by direct contact with nasal or throat secretions of infected people. People first develop a fever, then often a cough, runny nose and watery eyes, followed by an appearance of a rash. People are considered infectious four days before to four days after the appearance of the rash.

Two weeks ago it was reported an international traveler with measles visited multiple locations in Rockland and Westchester counties. Among the locations infected with measles was the Costco in Nanuet and Westchester Medical Center.

Rockland County has been offering free measles vaccines to help fight the outbreak and students without the vaccine have been ordered to stay home from school.

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