Members of Doctors Without Borders demonstrated in Geneva, after U.S. forces bombed the organization's hospital in the northern Afghanistan city of Kunduz. Fabrice Coffrini/AFP/Getty Images hide caption

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Some health workers in Liberia had stopped using the protective gear that was part of the Ebola routine. The photo above is from 2014, when the epidemic was at its peak. David P. Gilkey/NPR hide caption

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South America has a tradition of offering a haven to refugees, including my grandfather, Miguel Garsd, pictured here in Argentina, where he began practicing medicine in the 1930s. His family had fled pogroms in the Ukraine in the late 1800s. Courtesy of Jasmine Garsd hide caption

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This 11-year-old boy lives with his family in a Roma settlement in Belgrade. "He and his brothers and sisters are without documents, but he had this amazing confidence," Constantine says. Greg Constantine hide caption

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The antibiotic resistant bacteria have been found in pigs, pork and people in China. This pig is from a farm on the outskirts of Beijing. Peter Parks/AFP/Getty Images hide caption

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The Aedes mosquito can spread Zika virus in addition to dengue fever and chikungunya virus. The virus was first spotted in the Americas in 2014. Universal History Archive/UIG via Getty Images hide caption

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