External Link - Source: Science
Last year polio fighters could smell victory in Pakistan, which many believe will be the last country on Earth to harbor the virus. Cases dropped to an all-time low. Blood tests showed that immunity to the poliovirus had never been higher. Surely, there were not enough susceptible children to sustain transmission, and the virus would burn itself out within a year. Unsettling new findings, however, show it is far from gone.