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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