Molecular Epidemiology and Characterization of Campylobacter spp. Isolated from Wild Bird Populations in Northern England

Campylobacter infections have been reported at prevalences ranging from 2 to 50% in a range of wild bird species, although there have been few studies that have investigated the molecular epidemiology ofCampylobacter spp. Consequently, whether wild birds are a source of infection in humans or domestic livestock or are mainly recipients of domestic animal strains and whether separate cycles of infection occur remain unknown. To address these questions, serial cross-sectional surveys of wild bird populations in northern England were carried out over a 2-year period. Fecal samples were collected from 2,084 wild bird individuals and screened for the presence ofCampylobacter spp. A total of 56 isolates were recovered from 29 birds sampled at 15 of 167 diverse locales.Campylobacter jejuni ,Campylobacter lari , andCampylobacter coli were detected by PCR, and the prevalences of differentCampylobacter spp. in different avian families ranged from 0% to 33%. Characterization of 36C. jejuni isolates by multilocus sequence typing revealed that wild birds carry both livestock-associated and unique strains ofC. jejuni . However, the apparent absence of unique wild bird strains ofC. jejuni in livestock suggests that the direction of infection is predominantly from livestock to wild birds.C. lari was detected mainly in wild birds sampled in an estuarine or coastal habitat. FifteenC. lari isolates were analyzed by macrorestriction pulsed-field gel electrophoresis, which revealed genetically diverse populations ofC. lari in Eurasian oystercatchers (Haematopus ostralegus ) and clonal populations in magpies (Pica pica ).