Pansusceptible Escherichia coli isolates obtained from faeces of free-ranging Bairds tapirs (Tapirus bairdii) suggests a low selective pressure for resistance determinants in the northwestern region of the Talamanca Mountain Range, Costa Rica
Jorge RojasMuseo del Jade
Jorge Rojas Jiménez, Esteban Brenes-Mora, Paloma Alcázar-García, Randall Arguedas-Porras, Elías Barquero-Calvo
Antibiotic resistance is an emerging global problem that encompasses human and animal health. A main issue is an abusive and indiscriminant use of antibiotics, in which dissemination of resistant bacteria throughout the environment occurs. Wild animals, in rare occasions are expose to antibiotics, therefore antibiotic resistance levels in these animals are expected to be low. Nevertheless, as the interactions between humans, domestic and wild animals are increasing, there is a growing risk that the intestinal microbiota from wild animals may acquire resistant bacteria or genes mainly through oral exposition. The main objective of this study was to analyse the antimicrobial susceptibility profile of Escherichia coli isolates obtained from faecal samples of free-ranging Bairds tapirs (Tapirus bairdii) in the northwestern region of the Talamanca Mountain Range, Costa Rica. Faecal samples were collected by opportunistic search of the study area during seven field expeditions. Escherichia coli isolates were recovered using selective and differential MacConkey agar medium and were subjected to biochemical identification and antimicrobial susceptibility testing using a VITEK®2 Compact automated system and the AST-N279 card. A total of 60 E. coli isolates were obtained from 63 faecal samples. Following evaluation of nine different antimicrobial classes, 98% (59/60) of the isolates were characterized as pansusceptible; only 1 isolate presented resistance to nalidixic acid. We propose that the commensal intestinal microbiota of free-ranging Bairds tapirs in this area remains isolated from antibiotic selective pressure, probably because seven different protected areas converge, thus giving a possible low anthropogenic activity to the region. Protected areas consequently have a positive impact in protecting animals from antibiotic selective pressure. Hence, we consider this a contribution in terms of antimicrobial resistance, with the main aim to develop conservation strategies in regions near protected areas, such as antibiotic usage control by health authorities.