OUR PROGRESS AGAINST POLIO - ERADICATION STILL REMAINS CHALLENGE

Abstract

Polioviruses are enteroviruses that are transmitted direct from person to person or following excretion in feces or pharyngeal secretions. Because the poliovirus receptor is only expressed on human cells or on cells of few subhuman primate species, eradication is possible. In 1988 the Global Initiative for Polio Eradication (GIPE) at the 41st WHO summit announced that the main goal for 2000 is complete polio eradication. According the CDC reports the aim has not been reached yet, although the incidence of polio cases were decreased from 350,000 cases of wild polio virus in more than 125 endemic countries in 1988 to only 400 cases of polio reported in only 3 endemic countries (Nigeria, Afghanistan and Pakistan) in 2000. The last case of wild polio virus (wPV) was detected in 1997 in Serbia. In order to eradicate polio virus two vaccines are used- inactivated and live-attenuated polio vaccines. According to the studies oral polio vaccine has better efficacy and immunogenicity profile in comparison to inactivated polio vaccines, but due to safety reasons inactivated polio vaccine is now widely used (there is no risk of vaccine associated paralytic polio - VAPP and vaccine derived polio virus- VDPV). Although there are very effective and immunogenic vaccines available all over the world the polio eradication is not a simple project, in undeveloped and developing countries vaccines are not available, whereas in developed countries parents refused to vaccinate their children.