It has spread to many countries this year . It 's typically the low season for transmission of the disease . Pakistan , Nigeria and Cameroon are urged to put measures into place . ` A coordinated international response is deemed essential to stop this international spread of wild poliovirus and to prevent new spread with the onset of the high transmission season in May/June 2014 , '' according to the organization . No cases of polio were reported worldwide in 2014 , WHO says .
It has spread to many countries this year . It 's typically the low season for transmission of the disease . Pakistan , Nigeria and Cameroon are urged to put measures into place . No cases of polio were reported worldwide in 2014 , WHO says .