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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