An artist on Rio de Janeiro's Copacabana beach puts the final touches on a sand sculpture of the assassin bug, which spreads Chagas disease. The sculpture was part of an event in 2009 commemorating the 100th anniversary of the discovery of the disease.
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Afghan men wait to receive psychiatric treatment in a Kabul hospital. Scarred by decades of war, social problems and poverty, more than 60 percent of Afghans suffer from stress disorders and mental health problems.
A man readies a cow for the International Highland Cattle Show in Glasgow, Scotland. Researchers say genetics and the amount of time animals and humans spend together can affect how viruses spread between species.
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Laurence Fishburne as Dr. Ellis Cheever and Kate Winslet as Dr. Erin Mears in the thriller Contagion. Winslet's character was modeled on CDC epidemiologist Dr. Anne Schuchat.
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Women hold mosquito nets after receiving them at a distribution point in Sesheke, Zambia. Researchers say malaria may have rebounded in some parts of Zambia and Senegal because of resistance to the insecticide-treated nets.