Antimicrobial Resistance and Multilocus Sequence Types of Finnish Campylobacter jejuni Isolates from Multiple Sources.
Antimicrobial susceptibility was determined for 805 domestic Campylobacter jejuni isolates obtained from broilers (n = 459), bovines (n = 120), human patients (n = 95), natural waters (n = 80), wild birds (n = 35) and zoo animals/enclosures (n = 16) with known multilocus sequence types (MLST) for 450 isolates. The minimum inhibitory concentration (MIC) values for erythromycin, tetracycline, streptomycin, gentamicin and the quinolones ciprofloxacin and nalidixic acid were determined with the VetMIC method. MICs were compared with MLST types to find possible associations between sequence type and resistance. The proportions of resistant isolates were 5% (broilers), 6.3% (natural waters), 11.4% (wild birds), 11.6% (human patients), 16.7% (bovines) and 31.3% (zoo). The most common resistance among the human and bovine isolates was quinolone resistance alone while resistance to streptomycin alone was most often detected among the broiler isolates and tetracycline resistance was most commonly observed in the wild bird, water and zoo isolates. No or negligible resistance to erythromycin or gentamicin was detected. In all data, 12/26 of the tetracycline-resistant isolates were also resistant to streptomycin (P < 0.001) and the clonal complex (CC) ST-1034 CC showed a high proportion of 75% (9/12) of tetracycline-resistant isolates, most originating from the zoo and broilers with closely associated MLST types from these sources. No association between quinolone resistance and MLST type was seen. The low percentage of resistant isolates among the domestic Campylobacter infections is most probably due to the long-term controlled use of antimicrobials. However, the higher percentage of tetracycline resistance observed among the zoo isolates could present a risk for zoo visitors of acquisition of resistant C. jejuni. The resistance pattern of tetracycline and streptomycin most often found in ST-1034 CC could indicate a common resistance acquisition mechanism commonly present in this CC. Overall, MLST typing was found to be a useful method in recognition of potential genetic lineages associated with resistance.
Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
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Olkkola
The Finnish Food Safety Authority Evira, Helsinki, Finland.
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Nykäsenoja
The Finnish Food Safety Authority Evira, Helsinki, Finland.
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Raulo
Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
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Llarena
Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
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Kovanen
Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
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Kivistö
The Finnish Food Safety Authority Evira, Helsinki, Finland.
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Myllyniemi
Department of Food Hygiene and Environmental Health, Faculty of Veterinary Medicine, University of Helsinki, Helsinki, Finland.
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Hänninen
D000818:Animals; D000836:Animals, Zoo; D000900:Anti-Bacterial Agents / Q000493:pharmacokinetics* / Q000494:pharmacology; D002169:Campylobacter Infections / Q000188:drug therapy; D016123:Campylobacter jejuni / Q000187:drug effects*; D002417:Cattle; D002645:Chickens; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D005387:Finland; D006801:Humans; D058885:Multilocus Sequence Typing; D016133:Polymerase Chain Reaction; D014871:Water Microbiology
D000900:Anti-Bacterial Agents
Antimicrobial resistance; bovine; broiler; campylobacter; ciprofloxacin; environment; human; multilocus sequence types; streptomycin; tetracycline