There today, here tomorrow: A mother holds her child for a measles vaccination in Manila, Philippines, in January. Travelers are bringing measles from the Philippines to the United States.
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Public school student Julio Valenzuela, 11, grimaces as he gets a vaccination before the start of the school in Lynnwood, Calif., on Aug. 27. Vaccines are required for school attendance.
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A student gets vaccinated against pertussis at a Los Angeles middle school in 2012. The state required that students be immunized to halt an epidemic of whooping cough.
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