Aim: The present study was carried out to determine load of total bacteria, Escherichia coli and Salmonella spp. in dairy farm and its environmental components. In addition, the antibiogram profile of the isolated bacteria having public health impact was also determined along with identification of virulence and resistance genes by polymerase chain reaction (PCR) under a one-health approach. Materials and Methods: A total of 240 samples of six types (cow dung - 15, milk - 10, milkers' hand wash - 10, soil - 10 water - 5, and vegetables - 10) were collected from four dairy farms. For enumeration, the samples were cultured onto plate count agar, eosin methylene blue, and xylose-lysine deoxycholate agar and the isolation and identification of the E. coli and Salmonella spp. were performed based on morphology, cultural, staining, and biochemical properties followed by PCR. The pathogenic strains of E. coli stx1, stx2, and rfbO157 were also identified through PCR. The isolates were subjected to antimicrobial susceptibility test against 12 commonly used antibiotics by disk diffusion method. Detection of antibiotic resistance genes ereA, tetA, tetB, and SHV were performed by PCR. Results: The mean total bacterial count, E. coli and Salmonella spp. count in the samples ranged from 4.54±0.05 to 8.65±0.06, 3.62±0.07 to 7.04±0.48, and 2.52±0.08 to 5.87±0.05 log colony-forming unit/g or ml, respectively. Out of 240 samples, 180 (75%) isolates of E. coli and 136 (56.67%) isolates of Salmonella spp. were recovered through cultural and molecular tests. Among the 180 E. coli isolates, 47 (26.11%) were found positive for the presence of all the three virulent genes, of which stx1 was the most prevalent (13.33%). Only three isolates were identified as enterohemorrhagic E. coli. Antibiotic sensitivity test revealed that both E. coli and Salmonella spp. were found highly resistant to azithromycin, tetracycline, erythromycin, oxytetracycline, and ertapenem and susceptible to gentamycin, ciprofloxacin, and imipenem. Among the four antibiotic resistance genes, the most observable was tetA (80.51-84.74%) in E. coli and Salmonella spp. and SHV genes were the lowest one (22.06-25%). Conclusion: Dairy farm and their environmental components carry antibiotic-resistant pathogenic E. coli and Salmonella spp. that are potential threat for human health which requires a one-health approach to combat the threat.

Background and Aim: Houseflies (Musca domestica) are synanthropic insects which serve as biological or mechanical vectors for spreading multidrug-resistant bacteria responsible for many infectious diseases. This study aimed to detect antibiotic-resistant bacteria from houseflies, and to examine their resistance genes. Materials and Methods: A total of 140 houseflies were captured using sterile nylon net from seven places of Mymensingh city, Bangladesh. Immediately after collection, flies were transferred to a sterile zipper bag and brought to microbiology laboratory within 1 h. Three bacterial species were isolated from houseflies, based on cultural and molecular tests. After that, the isolates were subjected to antimicrobial susceptibility testing against commonly used antibiotics, by the disk diffusion method. Finally, the detection of antibiotic resistance genes tetA, tetB, mcr-3, mecA, and mecC was performed by a polymerase chain reaction. Results: The most common isolates were Staphylococcus aureus (78.6%), Salmonella spp., (66.4%), and Escherichia coli (51.4%). These species of bacteria were recovered from 78.3% of isolates from the Mymensingh Medical College Hospital areas. Most of the isolates of the three bacterial species were resistant to erythromycin, tetracycline, penicillin and amoxicillin and were sensitive to ciprofloxacin, ceftriaxone, chloramphenicol, gentamicin, and azithromycin. Five antibiotic resistance genes of three bacteria were detected: tetA, tetB, mcr-3, and mecA were found in 37%, 20%, 20%, and 14% isolates, respectively, and no isolates were positive for mecC gene. Conclusion: S. aureus, Salmonella spp., and E. coli with genetically-mediated multiple antibiotic resistance are carried in houseflies in the Mymensingh region. Flies may, therefore, represent an important means of transmission of these antibiotic-resistant bacteria, with consequent risks to human and animal health.

Aim: To detect antibiotic-resistant pathogenic Escherichia coli in house flies captured from various environmental settings. Materials & methods: Isolation and identification of E. coli was performed based on culture and PCR. Antimicrobial susceptibility testing was conducted using disk diffusion test. Detection of virulence and antimicrobial resistance genes was carried out using PCR methods. Results: The prevalence of E. coli in flies was 61% with highest in dairy farms (70.67%) followed by food centers (65.33%), dustbins (64%) and area close to hospital (44%). The prevalence rates of tetA, tetB, ereA, CITM, SHV, mcr-3 and catA1 resistance determinants were 88.75, 48.52, 41.67, 37.17, 27.77, 18.37 and 14.81%, respectively. Conclusion: Multidrug-resistant pathogenic E. coli are widely distributed in house flies, which requires a one-health approach to delineate their control.

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Objectives: This study was conducted to assess the prevalence and characterization of Staphylococcus aureus from chicken and quail eggshells and to study the antibiogram of the isolates. Materials and methods: A total of 300 eggs (220 chicken eggs and 80 quail eggs) were collected from different retail shops and farms in Mymensingh district. Swabs taken from the egg surfaces were cultured on Mannitol Salt Agar for the isolation of S. aureus . Polymerase chain reaction was conducted for confirmatory identification of the bacterial species targeting nuc gene, followed by confirmation of methicillin-resistant S. aureus by targeting the mecA gene. Antibiotic sensitivity test of the isolated bacteria was done against commonly used antibiotics by the disk diffusion method. Results: The prevalence of Staphylococcus spp. and S. aureus in the chicken eggshell surface was 20.45% and 10.45%, respectively. Similarly, the prevalence of Staphylococcus spp. and S. aureus in quail eggshell surface was 16.25% and 5%, respectively. Overall, 27 isolates were identified as S. aureus , of which 23 were from the chicken eggshell surface and four from quail eggshell surface. Among the seven isolates tested, overall four (57.14%) were positive for the nuc gene. On the other hand, the mecA gene could be detected in three (50%) S. aureus out of six oxacillin resistant isolates. The antibiogram study indicated that most of the isolates were resistant to the antibiotics under β-lactam group. Conclusion: The present study concludes that chicken and quail egg surface harbor multidrug-resistant bacteria which may cause public health hazards, if these antibiotic-resistant bacteria are transferred to a human.