Prevalence of antibiotic resistance in diarrheagenic Escherichia coli isolated from broiler

Abstract

Escherichia coli is the member of family Enterobacteriaceae commonly found in intestinal tract of humans and other animals. Most of its strains are harmless, but only few are reported to cause diseases in humans and also responsible for number of outbreaks. Some of the strains of E. coli cause gastroenteritis, meningitis and urinary tract infections. Some E. coli strains produce toxins and cause severe illnesses on ingestion. Worldwide, diarrhea and urinary tract infections are the most recognized symptoms of E. coli infections. A group of E. coli strains named DEC is most commonly found in developing and developed world. Diarrheagenic E. coli further consist of five disease causing strains: EHEC, EPEC, EAEC, EIEC, and ETEC. First of its strain named EHEC is responsible for life threatening hemolytic uremic syndrome (HUS) that is characterized by bloody diarrhea and kidney failure. First E. coli outbreak was related with consumption of undercooked hamburger contaminated with EHEC. Typical EPEC are found to be primary risk factor for infantile diarrhea. Among them, EPEC and EIEC are most common disease-causing agent in developing world. EAEC is found to be more common cause of diarrhea in immunocompromised persons. While ETEC is responsible for travelers’ diarrhea in international travelers from developed to developing countries. To control the bacterial infections in animals and humans, large quantities of antibiotics are used. Antibiotics are also fed to broiler for effective control of spread. Continuous exposure of these drugs to microbes ultimately develops resistance in pathogens against the used antibiotics. The load of resistant DEC in broiler meat and its spread to human population in Pakistan is unknown. In this study, samples of broiler feces and meat were collected from open markets of major districts of South Punjab (Khanewal. Multan, Dera Ghazi Khan and Bahawalpur), Pakistan. A total of 632 broiler fecal samples (of which 125 from semi-organic broiler), 400 from slaughtering shops (slaughterers hand, consumer hands, knife, cutting board etc), 150 samples of slaughterers feces and 150 of non-slaughterers feces were collected. Samples were analyzed for prevalence of E. coli. Isolates of E. coli were further characterized for prevalence rate of antibiotic resistance, Tet-resistance genes and virulence determinants.