UNLABELLED Four cases of acute flaccid paralysis caused by slightly evolved (Sabin-like) vaccine polioviruses of serotype 2 were registered in July to August 2010 in an orphanage of Biysk (Altai Region, Russia). The Biysk cluster of vaccine-associated paralytic poliomyelitis (VAPP) had several uncommon, if not unique, features. (i) Until this outbreak, Sabin-like viruses (in distinction to more...

Since the launch of the Global Polio Eradication Initiative (GPEI) in 1988 the global incidence of poliomyelitis has fallen by nearly 99 %. From a situation where wild type poliovirus was endemic in 125 countries across five continents, transmission is now limited to regions of just three countries - Pakistan, Afghanistan and Nigeria. A sharp increase in Pakistan's poliomyelitis cases in 2014 p...

Genetic marker tests were performed on 997 strains of poliovirus isolated from patients with neurological disease and from healthy people in England and Wales. Before the introduction of live attenuated vaccine most strains could multiply at raised temperatures. Now, however, many strains isolated from cases of poliomyelitis or from healthy persons with no known contact with vaccine cannot grow...