So cute, but not cuddly. The Egyptian tomb bat, Taphozous perforatus, is a likely carrier of the Middle East respiratory syndrome virus, or MERS. Courtesy of Jonathan H. Epstein/EcoHealth Alliance hide caption

itoggle caption Courtesy of Jonathan H. Epstein/EcoHealth Alliance

A dromedary camel waits for a tourist to hop on its back in Petra, Jordan. The country has recorded two cases of the Middle East respiratory syndrome. Chris Jackson/Getty Images hide caption

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Some scientists think new types of bird flus should arise only in chickens, not in labs. Here a worker collects poultry on a farm in Kathmandu, Nepal, where the H5N1 virus was infecting animals in October 2011. Prakas Mathema/AFP/Getty Images hide caption

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A man who just recovered from the H7N9 bird flu leaves a hospital in Bozhou, China, in April. Since early May, the number of new H7N9 cases has dramatically declined. AFP/Getty Images hide caption

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Buzz, Georgia Tech's mascot, wasn't the only bug in the students' midst last fall. An outbreak of bacterial pneumonia sickened at least 83 in what the CDC called the largest known outbreak at a university in 35 years. Collegiate Images/Getty Images hide caption

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Ali Maow Maalin said he avoided getting the smallpox vaccine as a young man because he was afraid of needles. He didn't want others to make the same mistake with polio. Courtesy of the World Health Organization hide caption

itoggle caption Courtesy of the World Health Organization

A harmful trio (from left): a deer tick, lone star tick and dog tick. Getty Images hide caption

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