MMR — the modern combination vaccine against measles, mumps and rubella — provides stronger, longer-lasting protection against measles than the stand-alone measles vaccine typically given in the U.S. in the early 1960s.
Scientists say low chlorine levels in Flint's water system during the city's water crisis in 2014 and 2015 led the bacterium Legionella pneumophila to proliferate, causing a deadly outbreak of Legionnaire's disease.
Workers spray to kill fleas in a public school in Antananarivo, Madagascar's capital. A bite from an infected flea can spread the plague, which has stricken 157 people in the island nation since August.
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Kenyan health officials take the temperatures of passengers arriving at the Nairobi airport on Thursday. Kenya has no reported cases of Ebola, but it's a transportation hub and so is on alert.
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