DETECTION AND CHARACTERIZATION OF DIARRHEAGENIC E. COLI ISOLATED FROM RIVER OF TERAI BELT OF PROVINCE NO. 1, NEPAL

Abstract

The most frequent human gut pathogens are E. coli strains. The majority of known E. coli strains are an etiologic cause of diarrhea in developing nations. The spread of enteric pathogens into flowing water is a significant issue linked with the disposal of these wastes. The study aimed to determine and characterize the diarrheagenic E. coli isolated from river water of terai belt of Province no.1. Altogether 43 river water sample were collected aseptically and transported to the laboratory, then the collected sample were enriched and cultured in EMB agar plate and incubated for 24 hrs at 37ºC. Furthermore, gram staining and biochemical test were performed for the colony having greenish metallic sheen. 18 positive isolated strains were subjected to antibiotic susceptibility tests, biofilm assays, MIC. The data were statistically analyzed with the help of SPSS version 25. From the study, the overall prevalence of E. coli was 41.86%. The sensitivity of E. coli isolates showed a significant difference in Amikacin, Cefotaxime, Nalidixic acid, and Chloramphenicol whereas Ciprofloxacin was most susceptible. Moreover, 72.22% were weak biofilm producers, followed by moderate biofilm producers i.e., 5.56%, and 22.22% of isolates were non biofilm producers. According to the study, 44.44% of E. coli isolates were sensitive to ciprofloxacin while 22.22% were resistant, 83.33% of isolates were resistant to Ampicillin while 11.11% were sensitive. The 7-gene multiplex PCR assays indicated that 0.14% (1/7) of isolates were harboring the stx2 gene and 57.14% (4/7) of isolates were harboring escV and invE genes. Virulent gene ent and pic was present in 14.28% (1/7) isolates. Atypical bfpB and bla AmpC gene harboring were detected in 42.85(3/7) isolates