Molecular detection of zoonotic pathogens causing gastroenteritis in humans: Salmonella spp., Shigella spp. and Escherichia coli isolated from Rattus species inhabiting chicken farms in North West Province, South Africa.

Rodents are key carriers and reservoirs of various pathogens of public health importance to both human and animal diseases. This research was carried out in order to identify the selected pathogens, namely, Shigella spp., Salmonella spp. and Escherichia coli from rats that inhabit the poultry houses. A total of 154 samples from captured rats were examined for the zoonotic bacterial pathogens, of which 3.3%, 29.9% and 20.7% were harbouring Shigella spp., Salmonella spp. , and E. coli , respectively. A total of 14 Shigella isolates expressed presence of ipa H gene, of which eight and five were positive for S. sonnei and S. boydii , respectively. For Salmonella , 68 isolates were positive for inv A and other genes including spy with 26 (38%), sdf I 2 (18%), spv C 14 (20%), hil A 28 (41%), mis L 43 (63%), orf L 31 (46%) and spi C 38 (56%). For E. coli , the aggR gene was the most prevalent (62 [42%]), followed by the eae gene, which was only detected in 21 (14%) isolates, while stx gene was not detected in any of the samples. This study shows that zoonotic pathogens with virulence genes are circulating in rodents from selected chicken farms in the North West Province of South Africa. Rodents must therefore be regarded as important carriers of zoonotic pathogens that can potentially infect both humans and animals.