The Ethiopian government has set up about a dozen vaccination booths along its thousand-mile border with Somalia. Jason Beaubien/NPR hide caption

itoggle caption Jason Beaubien/NPR

A young girl stands in the doorway of a home in Uttar Pradesh, India. The markings on the door show that a polio immunization team vaccinated children in the home. Alyce Henson/Courtesy of Rotary International hide caption

itoggle caption Alyce Henson/Courtesy of Rotary International

Hawah Alhassan, 5, contracted Guinea worm in a village near Tamale, Ghana, in 2007. The country eliminated the parasite in 2011. Wes Pope/MCT/Landov hide caption

itoggle caption Wes Pope/MCT/Landov

HIV-positive babies rest in an orphanage in Nairobi, Kenya. Treatment right after birth may make it possible for HIV-positive newborns to fight off the virus. Brent Stirton/Getty Images hide caption

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A nurse treats a cholera patient at the Juan Pablo Pina Hospital in San Cristobal, Dominican Republic, in August. Health officials say that the strain of cholera circulating in the country— the same one that first appeared in Haiti three years ago — has also caused outbreaks in Cuba and now Mexico. Erika Santelices/AFP/Getty Images hide caption

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Syrian opposition fighters sit on the front line in the city of Deir Ezzor on Oct. 13. Ongoing violence has ravaged the city since March 2011. AFP/Getty Images hide caption

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David Lozano (left) and Kevin Kreinbring stand in front of a painting created by Lozano. The couple says they get tested for HIV together every six months. Courtesy of David Lozano hide caption

itoggle caption Courtesy of David Lozano

Haitians protest against United Nations peacekeepers in Port-au-Prince in 2010. Hector Retamal/AFP/Getty Images hide caption

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Avez, 2, is held by his mother, as he receives the polio vaccine in the Khyber Tribal Region in northwest Pakistan. Daniel Berehulak/Getty Images hide caption

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A health worker administers the malaria vaccine at a clinical trial in Kilifi, Kenya. Joseph Okanga/Reuters /Landov hide caption

itoggle caption Joseph Okanga/Reuters /Landov

Scientists have discovered four new DEET-like mosquito repellents. Three of them are safe to eat. Courtesy of Pinky Kai/University of California, Riverside hide caption

itoggle caption Courtesy of Pinky Kai/University of California, Riverside

Streptococcus pyogenes shouldn't be taken lightly. Left untreated, an infection with germ can trigger an autoimmune disease that damages the heart. NIAID/Flickr.com hide caption

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