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.
A man lies in a newly opened Ebola isolation center in a closed school in Monrovia, Liberia, on Thursday. The official death toll of 1,000 people in four countries is likely below the actual number, the World Health Organization says.
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Yonta, 6, rests with her sister Montra, 3, and brother Leakhena, 4 months, under a mosquito net in the Pailin province of Cambodia — an epicenter of drug-resistant malaria.
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A health worker vaccinates a child during a polio campaign in Bannu, Pakistan, June 25. The Taliban threaten to kill vaccinators and parents who immunize their kids.
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Usman (right), 7 months, and Abdullah (left), 18 months, are held by their mothers while they wait to receive the polio vaccine at the Jalozai refugee camp near Peshawar, Pakistan.
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Medical workers treat Ebola patients at the Eternal Love Winning Africa hospital in Monrovia, Liberia. Three workers at the hospital, including Dr. Kent Brantly (left), have tested positive for Ebola.
Courtesy of Samaritan's Purse