RESUMO
During the last two decade; twelve wild type 1 poliovirus genotypes have been characterized in Africa. Several distinct clusters have been identified within some of them and appeared to be segregated geographically. This distribution could represent newly emerging genotypes and independent sustained circulation of these lineages or cross border transmission between countries of a single genotype followed by a different natural evolution in each country. Concurrent circulation of more than one poliovirus genotype was seen in Nigeria; Togo; Central Africa Republic and South Africa. The present study which has generated a meaningful overview of the endemic circulation of wild type 1 poliovirus in Africa; could be a basis for further evaluation of the impact of mass vaccination campaigns on wild type 1 poliovirus