Occurrence of extended-spectrum beta-lactamase producing E. coli in broiler farm workers and the farm environment in Chiang Mai-Lamphun, Thailand

Antimicrobial resistance is a major global public health threat. For example, extended-spectrum beta-lactamase (ESBL) producing Escherichia coli’s emergence has resulted in treatment failure and increase mortality. The following study was conducted to determine the occurrence of ESBL producing E. coli in broiler farm workers and the broiler farm environment in Chiang Mai-Lamphun, Thailand. Twenty-nine (60.4%) of 48 broiler farms had evidence of ESBL producing E. coli. ESBL producing E. coli was recovered from 43.8% of boot swabs, 12.5% of feed and 2.1% of water. Fifteen (55.7%) of 27 farm workers had ESBL producing E. coli recovered from rectal swab samples. All isolates were susceptible to imipenem but resistant to ampicillin. The ESBL producing E. coli isolate were highly resistant to streptomycin (94.3%), gentamicin (86.8%), tetracycline (77.4%), chloramphenicol (66.0%), nalidixic acid (58.5%), and sulfamethoxazole/trimethoprim (56.6%). A large percentage (96.2%) of isolates was classified as multidrug resistance (MDR). Thirty-five antimicrobial resistance profiles were identified with AMP-GEN-SXT-NAL-TET-CHL-STR, AMP-GEN-SXT-TET-CHL-STR (14.3%) as the 2 most prevalent antimicrobial resistant profiles. Common resistance profiles were observed between farm workers and farm environment. These findings suggest possible transmission between poultry flock and humans on broiler farms, likely from contact with birds or their environment. It is important to increase awareness of hygiene practices on broiler farms and control antimicrobial usage to limit the emergence and spread of ESBL producing E. coli.