Free-living Waterfowl as a Source of Zoonotic Bacteria in a Dense Wild Bird Population Area in Northeastern Spain

Abstract

Salmonella spp. and Campylobacter spp. are zoonotic bacteria that represent an economic and public health concern worldwide. Due to the difficulty to collect samples from free-living waterfowl, little is known on their importance as a reservoir of zoonotic agents. Thus, a study was conducted to determine the prevalence, genotypic diversity and antimicrobial susceptibility of Salmonella and Campylobacter from waterfowl in Ebro Delta (northeastern Spain), a geographical area with a dense wild bird population. Samples were collected from 318 adult waterfowl belonging to nine fowl species. All the samples were taken during the hunting season from 2008 to 2010. None of the birds were positive for Salmonella, while the overall Campylobacter prevalence was 12.58% (40/318). A much higher Campylobacter coli prevalence than Campylobacter jejuni was found (11.64% versus 0.94%). The species Fulica atra showed the highest Campylobacter prevalence (78.05%). ERIC-PCR of the isolates showed a high diversity of strains. Antimicrobial susceptibility testing of Campylobacter isolates showed that all the isolates were susceptible to the seven antibiotics tested.

Microdilution testing reveals considerable and diverse antimicrobial resistance of Escherichia coli, thermophilic Campylobacter spp. and Salmonella spp. isolated from wild birds present in urban areas

“…An investigation about C. jejuni isolates from homing pigeons kept in lofts found complete susceptibility to erythromycin and tetracycline but 46.0% of the isolates were resistant to ciprofloxacin (Teske et al 2013). In contrast, all 40 Campylobacter isolates (mainly C. coli) tested from free-living waterfowl in Spain were completely susceptible to ciprofloxacin, enrofloxacin, nalidixic acid, gentamicin, erythromycin, tetracycline and chloramphenicol using a disc diffusion method (Antilles et al 2015). The different methods used for AMR testing might be one of the reasons for the heterologous results between the different studies, apart from regional and host species differences.…”

Global Epidemiology of Campylobacter Infection

“…In contrast, 3.0% (6/200 birds) of pigeons and 20.0% (1/5 birds) of mallards carried C. jejuni (355). The prevalence of C. jejuni in waterfowl in northeastern Spain (318 adult waterfowl of nine fowl species) was 12.6% (356). A further study in Spain isolated C. jejuni from 1.0% (1/97 birds) of griffon vultures (357), while a study from the United States, conducted over the period from 2009 to 2010, isolated thermophilic Campylobacter species from 4.8% (9/188 birds) of captured wild birds (358).…”

Seabirds (Laridae) as a source of Campylobacter spp., Salmonella spp. and antimicrobial resistance in South Africa

“…Salmonella isolation procedure was as described by Antilles et al (2015). Briefly, isolation was performed by using buffered peptone water (Oxoid, Basingstoke, UK) pre-enrichment, followed by selective enrichment in Rappaport-Vassiliadis (Oxoid, Basingstoke, UK) and subculturing onto xylose lysine tergitol 4 agar (Merck, Darmstadt, Germany); we subcultured up to four presumptive colonies onto MacConkey agar, and confirmed the lactose-negative colonies as Salmonella spp.…”

“…We performed ERIC-PCR as previously described (Antilles et al, 2015), except that we used a 508C annealing temperature that is more adequate for Enterobacteriaceae. Primer pairs used were ERIC-F (5 0 -AAG TAA GTG ACT GGG GTG AGC G-3 0 ) and ERIC-R (5 0 -ATG TAA GCT CCT GGG GAT TCA C-3 0 ) (Versalovic et al, 1991).…”

“…The occurrence of Campylobacter and Salmonella in aquatic environments (Levantesi et al, 2012;Pitk€ anen, 2013) and in wildlife reservoirs is well documented (Hilbert et al, 2012;Greig et al, 2015). A wide variety of birds, including raptors, waterfowl, crows, pigeons and gulls, have been reported as asymptomatic carriers of these zoonotic agents (Molina-Lopez et al, 2011;Gargiulo et al, 2014;Antilles et al, 2015;Jurado-Tarifa et al, 2016;Konicek et al, 2016), with their risk of infection linked to their opportunistic feeding habits and their proximity to farms or livestock pastures (Ramos et al, 2010;Hald et al, 2016). Although some Campylobacter and Salmonella strains display an important host-specificity (Heithoff et al, 2008;Griekspoor et al, 2013), many strains or serovars infectious to humans are adapted to a generalist lifestyle (e.g., certain C. jejuni and C. coli strains or Salmonella serovars Typhimurium and Enteritidis) and have a broad-host range (Hoelzer et al, 2011;Dearlove et al, 2016).…”