Evolution, epidemiology and diversity of Corynebacterium diphtheriae: New perspectives on an old foe.

Evolution, epidemiology and diversity of Corynebacterium diphtheriae: New perspectives on an old foe. Infect Genet Evol. 2016 Jun 9;43:364-370 Authors: Sangal V, Hoskisson PA Abstract Diphtheria is a debilitating disease caused by toxigenic Corynebacterium diphtheriae strains and has been effectively controlled by the toxoid vaccine, yet several recent outbreaks have been reported across the globe. Moreover, non-toxigenic C. diphtheriae strains are emerging as a major global health concern by causing severe pharyngitis and tonsillitis, endocarditis, septic arthritis and osteomyelitis. Molecular epidemiological investigations suggest the existence of outbreak-associated clones with multiple genotypes circulating around the world. Evolution and pathogenesis appears to be driven by recombination as major virulence factors, including the tox gene and pilus gene clusters, are found within genomic islands that appear to be mobile between strains. The number of pilus gene clusters and variation introduced by gain or loss of gene function correlate with the variable adhesive and invasive properties of C. diphtheriae strains. Genomic variation does not support the separation of C. diphtheriae strains into biovars which correlates well with findings of studies based on multilocus sequence typing. Genomic analyses of a relatively small number of strains also revealed a recombination driven diversification of strains within a sequence type and i...
Source: Infection, Genetics and Evolution - Category: Genetics & Stem Cells Authors: Tags: Infect Genet Evol Source Type: research