At her home in the U.K., Malala Yousafzai reads her letter to the missing Nigerian schoolgirls. Courtesy of Malala Fund hide caption

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A year ago, Lina says her parents took her to Yemen because her grandmother was gravely ill. But when the family arrived, Lina's father announced that she would be getting married to a local man. Renee Deschamps/Getty Images/Vetta hide caption

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Secretary of State John Kerry and African Union Commission Chairperson Nkosazana Dlamini Zuma signed an agreement Monday to establish the first Centers for Disease Control and Prevention in Africa. The U.S. will provide technical advice and a few staff for the agency. Alex Wong/Getty Images hide caption

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

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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

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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

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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

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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

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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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