Sporadic dengue fever outbreaks in Florida in 2009 and 2010 spurred mosquito control efforts in Key West and Miami Beach, shown here. The same mosquito that carries dengue, Aedes aegypti,can transmit Zika.
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Pallets of bottled water are seen ready for distribution in a Flint, Mich., warehouse on Jan. 21. The warehouse is the emergency water supply for Flint residents affected by lead-contaminated water.
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