Why Polio Vaccines? NPR's Joanne Silberner reports on an emerging debate in the public health community. There is concern about whether polio can be totally eradicated from the world with existing vaccine strategies. The World Health Organization relies on the oral polio vaccine, which uses a weakened -- but not dead -- form of the polio virus. Some say that another vaccine, which uses killed virus, would ensure that polio is ended worldwide by 2003.