Loved ones express their grief at the burial of Ramon Romero Ramirez in Chichigalpa, Nicaragua, January 2013. The 36-year-old died of chronic kidney disease after working in the sugar cane fields for 12 years. Ramirez is part of a steady procession of deaths among cane workers. Ed Kashi/VII hide caption
By ensuring vaccines are invented and distributed, Bill Gates says, his foundation is dramatically reducing the number of childhood deaths in poor countries. Marie McGrory/NPR hide caption
An Egyptian Muslim prays during a ritual in Mina, Saudi Arabia, October 2013. Some people wore masks during the hajj pilgrimage last year to protect against the Middle East Respiratory Syndrome. Amr Nabil/AP hide caption
Gado Labbo holds her 5-year-old son, Yusuf, at a clinic in Dareta, Nigeria. In 2010, when Yusuf first entered the clinic, he had a blood lead level 30 times higher than the amount the Centers for Disease Control and Prevention considers dangerous. David Gilkey/NPR hide caption
Chemist Facundo Fernandez of the Georgia Institute of Technology tested morning-after pills collected from 15 different pharmacies in Lima, Peru. Rob Felt/Georgia Tech hide caption
A child receives a polio vaccine Sunday in Kano, Nigeria. The country is the primary source of the virus in Africa but appears to be making progress against the disease; the current outbreak in Cameroon that has spread to Equatorial Guinea came by way of Chad, not Nigeria. Sunday Alamba/AP hide caption
Street vendors sell chickens at a market in Phnom Penh, Cambodia, in early 2013. Last year Cambodia reported more cases of H5N1 bird flu than any other country. Mak Remissa/EPA /LANDOV hide caption
Not nice: A gut-eating amoeba (green) nibbles on a live human cell (purple) under the microscope. The parasite chews on the cell before killing and discarding it. Courtesy of Katy Ralston hide caption
Advocates demonstrate in favor of cheaper generic drugs to treat hepatitis C in New Delhi on March 21. The disease is common among people who are HIV positive. Saurabh Das/AP hide caption
The new normal in Guinea is washing hands with a mixture of water and bleach--shown here at the border entrance of Buruntuma, in the Gabu area on Tuesday. Tiago Petinga/EPA /LANDOV hide caption
A pregnant Somali woman gets a tetanus shot at a clinic in Mogadishu in 2013. The vaccination initiative was launched by the GAVI Alliance, UNICEF and the World Health Organization. Carl de Souza/AFP/Getty Images hide caption
A recent study reported that poor dental hygiene and excessive use of mouthwash containing alcohol could increase the risk of oral cancer. iStockphoto hide caption
Health specialists work in an isolation ward for patients in Guékedou, southern Guinea. Seyllou/AFP/Getty Images hide caption
Andrew Witty, CEO of GlaxoSmithKline, says that better control of infectious diseases in Africa is allowing chronic diseases to come to the surface. Mark Lennihan/AP hide caption
A boy waits to get vaccinated at an anti-polio campaign in Moradabad, India. Michaeleen Doucleff/NPR hide caption