A health worker administers drops of polio vaccine to children on a motorcycle in an outskirt of the Yemeni capital Sanaa April 7, 2014. Yemen's Ministry of Public Health and Population launched a ... more 
A health worker administers drops of polio vaccine to children on a motorcycle in an outskirt of the Yemeni capital Sanaa April 7, 2014. Yemen's Ministry of Public Health and Population launched a national polio immunization campaign on Monday, according to World Health Organization (WHO). REUTERS/Khaled Abdullah (YEMEN - Tags: HEALTH POLITICS) less 
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Reuters | Photo By Khaled Abdullah / REUTERS
Mon, Apr 7, 2014 6:55 AM EDT