WASHINGTON (AP) _ Development of one or more drugs to treat polio was recommended Thursday to provide protection in any outbreaks of the disease that might occur after vaccination programs are ended.
A worldwide vaccination effort cut the number of polio cases from more than 350,000 in 1988 to just 784 in 2003, and the World Health Organization hopes to reduce the number to zero in the next few years.
Once the disease is eliminated it will be difficult to maintain the effort to vaccinate people, and WHO plans to stop using the current vaccine three years after the last case is reported.
But there still might be outbreaks of polio, especially as the number of unvaccinated people grows, prompting a committee of the National Research Council to recommend developing antiviral medications to fight polio.
The current oral vaccine uses weakened but live polio virus which can spread to others from people who have been vaccinated. In that process the virus can sometimes regain its ability to cause illness. The injected vaccine more often used in the United States uses dead virus.
The committee also expressed concerns that in some people with weakened immune systems the live virus can develop into a continuing infection in which they shed the virus for an unknown length of time.
While the number of these individuals is exceedingly small, the committee said, their actual number cannot yet be determined.
``The development of one or more antiviral drugs against poliovirus, although expensive, serves as an insurance policy that provides an additional means of reacting to repeated outbreaks due to continued circulation of vaccine-derived strains, should they occur,'' the committee concluded.
The National Research Council is an arm of the National Academy of Sciences, an independent organization chartered by Congress to advise the government on scientific matters.