Detección de genes de virulencia del patotipo enteroagregativo en cepas de Escherichia coli aisladas de fuentes de agua subterránea de la provincia del Chaco, Argentina

Abstract

Groundwater is an important source of drinking water for many communities in Northern Argentina; particularly, in the province of Chaco, where about 14% of households use this natural resource. Enteroaggregative Escherichia coli is an emerging pathogen whose global importance in public health has increased in recent years. Despite the significant risk of disease linked to contaminated water exposure, the prevalence of E. coli pathotypes in aquatic environments is still not so well defined. The aim of the present study was to detect the presence of typical enteroaggregative E. coli through the recognition of its virulence factors aap, AA probe and aggR by molecular techniques. A total of 93 water samples from different small communities of Chaco were analyzed. E. coli was identified in 36 (38.7%) of the tested samples. Six strains isolated from different samples harbored the studied genes. Of these 6 isolates, 3 carried the aap gene, 2 the AA probe and the last one the combination of aap/aggR genes. The prevalence of E. coli isolates harboring enteroaggregative virulence genes in groundwater sources was 6.4%. This work represents the first contribution to the study of the presence and distribution of virulence genes of EAEC in groundwater sources in this region of Argentina.

Variedad bacteriana en cultivos piscícolas y su resistencia a antibacterianos

“…Variados estudios en peces y ambientes acuáticos en India, Vietnam, Egipto, Argentina, Chile y otros países, han corroborado la presencia de bacterias resistentes a múltiples antibióticos como cloranfenicol, polimyxina B, oxitetraciclina, ciprofloxacina, streptomicina, gentamicina, amoxicilina, ampicilina, novoviocina, nitrofurantoína, trimetoprim-sulfa y ácido nalidixico (Ishida et al, 2010;Sarter et al, 2007;Hathaa et al, 2005;Lösch et al, 2005;Miranda et al, 2003;Teuber, 2001). En la actualidad, el mayor problema es la resistencia de un mismo microorganismo a múltiples medicamentos y la transferencia horizontal de resistencia entre diferentes especies bacterianas, lo que dificulta el tratamiento de enfermedades infecciosas.…”