Isolation of multidrug-resistant Escherichia coli, Staphylococcus spp., and Streptococcus spp. from dogs in Chattogram Metropolitan Area, Bangladesh

Objectives: Antibacterial resistance is a great concern in human and food animal medicine, andit poses a significant concern in pet animals like dogs. This cross-sectional study was conductedto evaluate the antimicrobial resistance pattern of Escherichia coli, Staphylococcus spp., andStreptococcus spp. along with the carryover of some resistance genes in E. coli from dogs in theChattogram metropolitan area, Bangladesh.Materials and Methods: Rectal swab (n = 50), nasal swab (n = 50), and skin swab (n = 50) sam-ples were collected from dogs having respiratory infections, skin infections, and/or enteritis,respectively. Three types of bacteria were identified and isolated by conventional bacteriologicaltechniques and biochemical tests. Antimicrobial susceptibility testing was carried out against 12antimicrobials by disk diffusion methods. Six resistance genes, namely blaTEM, blaCTX-M, tetA, tetB,Sul-I, and Sul-II, were screened for phenotypically resistant E. coli isolates by the polymerase chainreaction.Results: A total of 39 (78%) E. coli, 25 (50%) Staphylococcus spp., and 24 (48%) Streptococcus spp.isolates were isolated from the rectal swab, nasal swab, and skin swab samples, respectively. Inthe cultural sensitivity test, the E. coli isolates showed resistance to ceftriaxone (79%) and sulfa-methoxazole/trimethoprim (64%). Doxycycline (80%) demonstrated the highest resistance amongStaphylococcus isolates, followed by sulfamethoxazole/trimethoprim (60%). Streptococcus iso-lates showed the highest resistance to penicillin (63%), followed by ceftriaxone (54%), while noisolate showed resistance to gentamycin. The prevalence of blaTEM, blaCTX-M, tetA, tetB, Sul-I, andSul-II genes in phenotypically resistant E. coli isolates were 100%, 61.29%, 100%, 8.33%, 56%, and72%, respectively.Conclusions: Spillover of such multidrug-resistant bacteria and resistance genes from pet dogspose a serious public health risk.