Mother Daniele Santos holds her baby Juan Pedro, who has microcephaly, on May 30, 2016, in Recife, Brazil. Researchers are now learning that Zika's effects can appear up to a year after birth.
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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.
Key Haven, a Florida neighborhood about a mile east of Key West, is where a test of Oxitec's genetically engineered mosquitoes might take place later this year. Some neighbors have strongly dissented — at public meetings and via yard signs.
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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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.
The World Cup will come to the Arena de Sao Paola, shown here when it was under construction last fall. Brazil is also making a big push to control the local mosquitoes that can spread dengue fever.
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Chiara Andolina, a malaria researcher in Thailand, feeds her mosquito colony by letting the insects bite her right arm. These mosquitoes are picky and will dine only on live human blood.
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