Marqui Ducarme is aided by his wife after catching chikungunya at his home in Port-au-Prince, May 23. The virus swept through Haiti this spring, infecting more than 40,000 people.
A doctor gives a polio vaccine to a child at a health clinic in Baghdad last week. The CIA says it banned the use of vaccine programs as cover for spying last year — a practice health officials said had wide repercussions.
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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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Ads often tout dietary supplements and vitamins as "natural" remedies. But studies show megadoses of some vitamins can actually boost the risk of heart disease and cancer, warns Dr. Paul Offit.
Luke Tanner, 7, gets vaccinated for measles at a clinic near Swansea, Wales, in April. Wales is at the center of a measles outbreak that has been linked to one death.
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