Safe and small: The credit-card-sized test for anthrax destroys the deadly bacteria after the test completes. Courtesy of Sandia Nation hide caption

itoggle caption Courtesy of Sandia Nation

Maria Carmen Castro, 46, of Lima, Peru, is a survivor of MDR-TB — multidrug-resistant tuberculosis. Partners In Health treated her and loaned her money to open a small store. "Because of my TB and thanks to God and Partners In Health, now I have my own business," she says. Jason Beaubien/NPR hide caption

itoggle caption Jason Beaubien/NPR

The European Union banned the use of antibiotics to boost animals' growth in 2006. At first, the ban had little effect on the amount of drugs given to pigs. Carsten Rehder/Corbis hide caption

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The effects of malaria in the brain are clear: A healthy brain, right, has many grooves and crevices. But when the brain swells up, left, these crevices smooth out. Courtesy of Michigan State University hide caption

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Brazilian mothers participate in a demonstration in 2011 for the right to breastfeed in public, in Sao Paulo, Brazil. Eduardo Anizelli/STF/LatinContent/Getty Images hide caption

itoggle caption Eduardo Anizelli/STF/LatinContent/Getty Images

A mother feeds her new baby at the Yida refugee camp in South Sudan, which has the highest maternal mortality rate in the world. About 1 in 7 women in South Sudan die from causes related to pregnancy. Paula Bronstein/Getty Images hide caption

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Health workers are disinfected with a chlorine solution after treating patients at the Hastings Ebola Treatment Center in Freetown, Sierra Leone. Nine American aid workers have contracted Ebola while working in West Africa. David Gilkey/NPR hide caption

itoggle caption David Gilkey/NPR

Physicians Nowiba Mugambi and Erica Palys discuss a patient's X-ray at the Moi Teaching and Referral Hospital in Eldoret, Kenya. The hospital plans to open a new cancer treatment center in April. Evelyn Hockstein/Courtesy of AMPATH hide caption

itoggle caption Evelyn Hockstein/Courtesy of AMPATH

Smoke rises from chimneys of coal-based power plants in the Sonbhadra District of Uttar Pradesh, India. The Washington Post/Getty Images hide caption

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Burmese migrant Thazin Mon Htay and her father Ko Ngwe Htay were trafficked to Thailand to peel shrimp. They worked 16-hour shifts, seven days a week, for less than $10 a day, Ko Ngwe told PBS NewsHour. Jason Motlagh/Pulitzer Center on Crisis Reporting for NPR hide caption

itoggle caption Jason Motlagh/Pulitzer Center on Crisis Reporting for NPR

The rapid Ebola test from Corgenix Medical Corporation is small and easy to use. But because it involves blood, health workers would still need to run the test at a lab to stay safe. Courtesy of Corgenix Medical Corp. hide caption

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A health worker with Doctors Without Borders carries a child suspected of having Ebola at the treatment center in Paynesville, Liberia, last October. Ebola is especially deadly for young children and babies. About 4 in 5 infected died. John Moore/Getty Images hide caption

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You want that soda bottle. But it may not be because you crave soda. It might just be that you love the idea of wrapping your fingers around its enticing shape. Ariel Zambelich/NPR hide caption

itoggle caption Ariel Zambelich/NPR

Dr. Kwan Kew Lai volunteered for six weeks at an Ebola treatment center run by International Medical Corps in Bong, Liberia. Courtesy of Kwan Kew Lai hide caption

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Random violence in Syria makes it a dangerous place for aid workers. This month, members of the Syrian Arab Red Crescent transported Syrians from a rebel area to a part of Aleppo controlled by the Assad regime. Baraa Al-Halabi/AFP/Getty Images hide caption

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This World Health Organization map shows the percent of the population vaccinated for measles in each country in 2013. Dark green is at least 90 percent. Light green is 80 to 89 percent. Orange is 50 to 79 percent. Red is less than 50 percent. Courtesy of WHO hide caption

itoggle caption Courtesy of WHO

Dr. Margaret Chan, director-general of the World Health Organization, has said of Ebola: "It overwhelmed the capacity of WHO, and it is a crisis that cannot be solved by a single agency or single country." Fabrice Coffrini/AFP/Getty Images hide caption

itoggle caption Fabrice Coffrini/AFP/Getty Images

The number of children who need glasses has risen quickly across East Asia and Southeast Asia. But some parents and doctors in China are skeptical of lenses. They think glasses weaken children's vision. Imaginechina/Corbis hide caption

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