Progress toward poliomyelitis eradication--Pakistan and Afghanistan, January 2006-February 2007.

Of the four countries where wild poliovirus (WPV) transmission has never been interrupted, two are in the World Health Organization's (WHO) Eastern Mediterranean Region: Pakistan and Afghanistan. During January 2006-February 2007, the number of reported WPV cases in both countries increased. In addition, an increase was observed in the number of affected districts; however, genetic diversity of the virus decreased, and regions of transmission remained limited. This report updates a previous report and describes polio cases and eradication activities in Pakistan and Afghanistan during January 2006-February 2007. Critical to the success of polio eradication will be high vaccination coverage among children in areas of frequent conflict along the border between these two countries.