Evaluation of a PCR targeting fimbrial subunit gene (fimA) for rapid and reliable detection of Enteroaggregative Escherichia coli recovered from human and animal diarrhoeal cases

Characterization of chicken eggs associated Escherichia coli and Staphylococcus aureus for biofilm production and antimicrobial resistance traits

The present study assessed the prevalence, virulence characteristics, antimicrobial resistance and biofilm-forming ability of E. coli and S. aureus recovered from egg samples in Ludhiana, Punjab. A total of 393 samples from hatcheries (n = 238), retail shops (n = 94), and households (n = 61) were collected. The prevalence of E. coli was observed as 11.70% and 9.16% for S. aureus. A total of 41.30% of E. coli isolates were positive for aggR gene and 52.17% were for fimA gene; while 36.11% of the S. aureus isolates were positive for coa gene. A high proportion of E. coli (76.10%) and S. aureus (69.44%) isolates were resistant toward ≥3 tested antibiotic classes. A total of 39.13% of E. coli isolates were moderate biofilm former, whereas the majority of the S. aureus (41.67%) were weak biofilm former. No significant difference regarding biofilm formation was observed between MDR and non-MDR isolates of E. coli and S. aureus. Biofilm genes viz., fimC and crl were reported in 43.47% and 80.43% of E. coli isolates, respectively; while icaA and icaD genes were reported in 58.34% and 47.22% of S. aureus isolates, respectively. A strong metabolic activity among 52.17% of E. coli and 41.66% of S. aureus isolates was observed using XTT assay. The present study highlights the need for applied food safety measures across the egg production chain of the region to prevent the development of MDR strains and biofilms.

Antimicrobial resistance of Escherichia coli isolated from retail foods in northern Xinjiang, China

To determine antimicrobial resistance, 431 samples of retail foods purchased at different supermarkets in Northern Xinjiang were examined in this study. There were 112 Escherichia coli strains that were isolated, with approximately 26% of the samples contaminated by E. coli. The detection rate of E. coli isolated from pork was the highest (59.6%), followed by mutton (52.6%), retail fresh milk (52.4%), duck (36.4%), beef (35.3%), chicken (33.3%), and ready-to-eat food (12.9%); the E. coli detection rate for fish and vegetables was <11%. The result showed that the 112 isolates were mostly resistant to tetracycline (52%), followed by ampicillin (42%), compound trimethoprim/sulfamethoxazole (37%), amoxicillin (33%), and nalidixic acid (32%), imipenem resistance was not detected. One hundred isolates carried at least one antimicrobial resistance gene. The detection rate of resistance genes of our study was as follows: tetA (38%), tetB (27%), bla OXA (40%), bla TEM (20%), floR (20%), sul1 (16%), sul2 (27%), aad Ala (19%), aadB (11%), strA (28%), and strB (24%); tetC and bla PSE were not detected. Virulence genes fimC, agg, stx2, fimA, fyuA, papA, stx1, and eaeA were found in 52, 34, 21, 19, 6, 3, 2, and 2 isolates, respectively; papC was not detected. There was a statistically significant association between fimC and resistance to ciprofloxacin (p = .001), gentamicin (p = .001), amikacin (p = .001), levofloxacin (p = .001), and streptomycin (p = .001); between fimA and resistance to tetracycline (p = .001), ampicillin (p = .001), compound trimethoprim/sulfamethoxazole (p = .001), and amoxicillin (p = .003); between agg and resistance to gentamicin (p = .001), tetracycline (p = .001), ciprofloxacin (p = .017), and levofloxacin (p = .001); and between stx2 and resistance to ampicillin (p = .001), tetracycline (p = .001), compound trimethoprim/sulfamethoxazole (p = .002), and amoxicillin (p = .015).