President Obama meets with Emory University doctors and health care workers during his visit Tuesday to the Centers for Disease Control and Prevention in Atlanta.
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Dr. Tom Frieden, director of the CDC, talks with staff from Doctors Without Borders during a visit to the nonprofit group's newest Ebola treatment center in Monrovia, Liberia.
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A health worker vaccinates a child during a polio campaign in Bannu, Pakistan, June 25. The Taliban threaten to kill vaccinators and parents who immunize their kids.
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