Virulence Genes of Pathogenic Escherichia coli in Wild Red Foxes (Vulpes vulpes)

SIMPLE SUMMARY: Escherichia coli is a commensal of the intestinal tract of humans and animals, but some pathotypes can cause severe infections. Enteropathogenic E. coli (EPEC), Shiga toxin-producing E. coli (STEC), and enterohemorrhagic E. coli (EHEC) are the pathotypes most frequently involved in enteric disorders observed in people and domestic animals. Wildlife may harbor and excrete these pathotypes too, therefore, they may be source of infections for humans and domestic animals. Vulpes vulpes seem to be involved in the epidemiology of pathogenic E. coli strains, and thus they could be a relevant threat mainly when they invade human settlements in rural and urban areas. ABSTRACT: Different pathotypes of Escherichia coli can cause severe diseases in animals and humans. Wildlife may contribute to the circulation of pathogenic pathotypes, including enteropathogenic E. coli (EPEC), Shiga toxin-producing E. coli (STEC), and enterohemorrhagic E. coli (EHEC). This study analyzed 109 DNA samples previously extracted from fecal specimens collected from red foxes (Vulpes vulpes) to detect E. coli virulence genes eaeA, hlyA, stx1, and stx2, that characterize the EPEC, STEC, and EHEC strains. Thirty-one (28.4%) samples were positive for at least one investigated virulence gene: eaeA gene was detected in 21 (19.2%) samples, hlyA in 10 (9.1%), stx1 in 6 (5.5%), and stx2 in 4 (3.6%). Nine DNA samples resulted positive for two or three virulence genes: five (4.6%) samples were positive for eaeA and hlyA genes, two (1.8%) for eaeA and stx1, one (0.9%) for hlyA and stx1, one (0.9%) for eaeA, hlyA and stx2. Red foxes seem to be involved in the epidemiology of these infections and their role could be relevant because they may be source of pathogenic E. coli for other wild animals, as well as domestic animals and humans.