Antimicrobial Resistance and Genetic Diversity of Campylobacter spp. Isolated from Broiler Chicken at Three Levels of the Poultry Production Chain in Costa Rica

Abstract

Campylobacter spp. is considered the most common bacterial cause of human gastroenteritis, one of the four main causes of diarrheal disease worldwide, and one of the main foodborne pathogens causing hospitalizations and deaths. A total of 148 strains of Campylobacter spp. isolated from poultry at farms, processing plants and retail stores in Costa Rica were examined for resistance to six antibiotics. An agar dilution test was used to determine the minimum inhibitory concentration and susceptibility profiles against doxycycline, ciprofloxacin, nalidixic acid, enrofloxacin, chloramphenicol and erythromycin. In addition, a PFGE analysis was carried out to determine the genotype relatedness of a representative subset of the isolates. Around 92% (136/148) of the analyzed isolates showed resistance to the tested drugs. Nalidixic acid, ciprofloxacin and enrofloxacin, were the antibiotics for which resistance occurred most frequently (91.2%, 85.8% and 85.8%, respectively); followed by doxycycline (25.0%), chloramphenicol (5.4%) and erythromycin (2.7%). The profile conferring only resistance to quinolones was the most frequently found in this study, and only 2.0% of the isolates showed resistance to quinolones and macrolides simultaneously. Results showed a high frequency of resistant Campylobacter spp. strains, and evidenced the distribution, selection, and circulation of resistant strains along the poultry chain from farms to consumers. Cross contamination and resistance seem to play an important role in the dissemination of these strains at specific points of the poultry chain even when control measures are being taken. The establishment of effective surveillance and control strategies represents an essential tool for foodborne diseases mitigation. The rational use of antibiotics, especially those still showing efficacy, should be a priority issue in both human and veterinary medicine in order to contain the progress of this phenomenon and its consequences.

Prevalence of Campylobacter spp. in broilers in North Lebanon

“…This is in agreement with other studies that showed 30% of false negatives by culture compared to PCR [43]. Polymerase chain reaction results showed a rate of 88%, confirming previously published data on the search for Campylobacter of avian origin in Brazil (100% prevalence) [44], in Costa Rica (80%) [45], and in Sri Lanka (63.8%) [46]. Excessive use of antibiotics could cause culture failure in a high number of false negative cases.…”