Molecular epidemiology of serotype O foot-and-mouth disease virus with emphasis on West and South Africa

Genetic relationships of serotype O foot-and-mouth disease (FMD) viruses re covered from outbreaks of the disease in the West African countries of Nige r, Burkina Faso and, Ghana (1988-1993) and those from South Africa (2000) w ere determined by partial VP1 gene characterization. A 581-bp fragment, cor responding to the C-terminus half of the 1D (VP1 gene) region was amplified and sequenced. An homologous region of 495 nucleotides was ultimately used to determine genetic relationships of serotype O viruses from the Middle E ast, Europe, South America, North Africa, East Africa, southern Africa and Asia. Seven distinct type O genotypes were identified by phylogenetic recon struction, consisting of viruses from the following geographical regions: G enotype A: Asia, the Middle East, and South Africa, Genotype B: East Africa , Genotype C: West and North Africa, Genotype D: Taiwan and Russia, Genotyp e E: Angola and Venezuela, Genotype F: Western Europe, and Genotype G: Euro pe and South America. The genotypes constitute three different evolutionary lineages (I-III), which correspond to three discrete continental regions, some of which display inter-continental distributions due to introductions. Results further indicate that the outbreaks in Burkina Faso (1992) and Gha na (1993) are part of the same epizootic and that the strain involved in a recent outbreak of the disease in South Africa is most closely related (97% sequence identity) to a 1997 Bangladesh strain.