The Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report, released Thursday, said 207 or 13 percent of the reported cases were from 15 previously polio-free countries, and 143 or 9 percent of polio cases were reported from four countries -- Angola, Chad, Democratic Republic of Congo and Sudan -- previously polio-free.
"In response to continued wild poliovirus type 1 and wild poliovirus type 3 transmission in all endemic countries and re-established transmission in some previously polio-free countries, a new Global Polio Eradication Initiative strategic plan for 2010 to 2012 has been developed and is being implemented," the report said.
"Globally, careful monitoring of indicators during 2010–2012 and implementing corrective actions will be essential for polio eradication efforts to succeed."
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