A girl is vaccinated against dengue as part of a public immunization program for children in the Philippines. The program was suspended after the company raised safety concerns about the vaccination.
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Monsoon rains flooded Mumbai in August 2017. Aedes aegypti mosquitoes can spread diseases like dengue fever. Drought has affected the health of Somalians.
(From left) Punit Paranjpe/AFP/Getty Images; Christophe Simon/AFP/Getty Images; Arif Hudaverdi Yaman/Anadolu Agency/Getty Images
A worker fogs a neighborhood on the outskirts of Colombo in Sri Lanka in an effort to ward off mosquitoes. The country is facing an outbreak of dengue fever, a mosquito-borne disease.
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A common house mosquito (Culex pipiens) is about to sink her six-weaponed proboscis into a human arm. This type transmits West Nile virus by biting infected birds, then biting humans.
Previous experience with dengue outbreaks in Puerto Rico has shown that even small amounts of standing water — as in the vases of cemeteries — can serve as breeding areas for the mosquitoes that carry dengue and Zika.
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While some scientists seek ways to stop the spread of Zika by mosquitoes, others have received new funding from the National Institutes of Health to track the genes and habits of the virus itself.