Polio incidence dropped more than 99 percent since the launch of global polio eradication efforts in 1988 and no polio cases have been reported since January 2011 in India, one of the four remaining endemic countries, a CDC report said.
"Nevertheless, poliovirus transmission is ongoing in the other three endemic countries -- Afghanistan, Nigeria and Pakistan -- and travelers have carried the infection back to 39 previously polio-free countries over the last several years," it said.
"Three of these countries -- Angola, Chad and Democratic Republic of the Congo -- have continued to experience transmission of poliovirus for more than one year, raising concerns that a window of opportunity to eradicate this crippling and sometimes deadly disease may be closing. It is therefore imperative that we give this final push toward eradication our best effort."
Dr. Thomas R. Frieden, the CDC director, said: "If we fail to get over the finish line, we will need to continue expensive control measures for the indefinite future. More importantly, without eradication, every year polio could disable or kill more than 100,000 children."
The CDC said it will provide technical assistance and vaccination campaign planning, seek effective innovations to identify and vaccinate children and provide other help to countries most threatened