Virulence Determinants and Multidrug Resistance of Escherichia coli Isolated from Migratory Birds

Md Saiful Islam; Md Mehedi Hasan Nayeem; Md Abdus Sobur; Samina Ievy; Md Amirul Islam; Saifur Rahman; Md Abdul Kafi; Hossam M Ashour; Md Tanvir Rahman

doi:10.3390/antibiotics10020190

Virulence Determinants and Multidrug Resistance of Escherichia coli Isolated from Migratory Birds

Antibiotics (Basel). 2021 Feb 15;10(2):190. doi: 10.3390/antibiotics10020190.

Authors

Md Saiful Islam¹, Md Mehedi Hasan Nayeem¹, Md Abdus Sobur¹, Samina Ievy¹, Md Amirul Islam¹, Saifur Rahman¹, Md Abdul Kafi¹, Hossam M Ashour^{2

3}, Md Tanvir Rahman¹

Affiliations

¹ Department of Microbiology and Hygiene, Faculty of Veterinary Science, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh.
² Department of Integrative Biology, College of Arts and Sciences, University of South Florida, St. Petersburg, FL 33701, USA.
³ Department of Microbiology and Immunology, Faculty of Pharmacy, Cairo University, Cairo 11562, Egypt.

Abstract

Migratory birds are carriers of multidrug resistant pathogenic Escherichia coli. However, their roles in the dissemination of these resistant pathogens are still being neglected in Bangladesh. The present study was therefore carried out to detect multidrug resistant E. coli. In addition, these isolates were also screened for the presence of avian pathogenic E. coli (APEC)-associated virulence genes. A total of 66 fecal matter samples of migratory birds were screened. E. coli were isolated and identified by culturing and biochemical tests followed by polymerase chain reaction (PCR). APEC-associated virulence genes were detected by PCR. Disk diffusion assays were employed to investigate antibiogram profiles. Bivariate analysis was performed to assess correlations in resistance patterns between antimicrobials and to assess associations between virulence genes of E. coli. Among the 66 samples assessed by PCR, 55 (83.33%) were found positive for E. coli. Of these 55 isolates, the APEC-associated virulence gene fimC was detected in 67.27% of the isolates, which was significantly higher than in the cases of iucD (29.09%) and papC (5.45%) genes. In addition, three isolates were found positive for all three virulence genes, while 23 and 12 isolates were positive for one and two virulence genes respectively. In the bivariate analysis, significant associations were detected between fimC and iucD virulence genes. Using the antibiogram, all E. coli isolates were found to be multidrug resistant (MDR). The isolates exhibited 100% resistance against ampicillin and erythromycin in addition to varying percentages of resistance against streptomycin, tetracycline, ciprofloxacin, and chloramphenicol. Highly positive correlations between tetracycline and ciprofloxacin, chloramphenicol and ciprofloxacin, chloramphenicol and tetracycline were observed by bivariate analysis. To the best of our knowledge, this is the first study that reports APEC-associated virulence genes of MDR E. coli from migratory birds in Bangladesh. Results indicate that migratory birds are reservoirs of MDR E. coli isolates carrying APEC-associated virulence genes, which can seriously contribute to the development of human and animal diseases.

Keywords: APEC; E. coli; MDR; environment; migratory birds; public health; virulence.