A health staff member takes a blood sample from a child at a clinic operated by Doctors Without Borders in Bagega Village in northwestern state of Zamfara, Nigeria, on August 14, 2013.
A health staff member takes a blood sample from a child at a clinic operated by Doctors Without Borders in Bagega Village in the northwestern state of Zamfara, Nigeria, on August 14, 2013.  REUTERS/Akintunde Akinleye