The impacts of hedgehog (Erinaceus europaeus) Salmonella infection on public health and on animal welfare and conservation are unknown. We isolated Salmonella Enteritidis multi-locus sequence-type (ST)183 from 46/170 (27%) hedgehog carcasses (27 S. Enteritidis phage type (PT)11, 18 of a novel PT66 biotype and one with co-infection of these PTs) and from 6/208 (3%) hedgehog faecal samples (4 PT11, 2 PT66) from across Great Britain, 2012-2015. Whole genome phylogenetic analysis of the hedgehog isolates and ST183 from people in England and Wales found that PT11 and PT66 form two divergent clades. Hedgehog and human isolates were interspersed throughout the phylogeny indicating that infections in both species originate from a common population. PT11 was recovered from hedgehogs across England and Scotland, consistent with endemic infection. PT66 was isolated from Scotland only, possibly indicating a recent emergence event. People infected with ST183 were four times more likely to be aged 0-4 years than people infected by the more common ST11 S. Enteritidis. Evidence for human ST183 infection being non-foodborne included stronger correlation between geographic and genetic distance, and significantly increased likelihood of infection in rural areas, than for ST11. These results are consistent with hedgehogs acting as a source of zoonotic infection.
Bibliographical noteFunding Information:
Thanks to Tim Hopkins, Ricardo Castro Cesar de Sa and Lucy Sangster for assistance with collation and receipt of hedgehog samples for testing. We also thank staff at the East Sussex Wildlife Rescue and Ambulance Service, Gower Bird Hospital, RSPCA East Winch, RSPCA Stapeley Grange, RSPCA West Hatch, Shepreth Hedgehog Hospital, Colin Seddon and the Scottish SPCA National Wildlife Rescue Centre, Vale Wildlife Hospital and Rehabilitation Centre for providing samples, without which this research would not have been possible. The staff of the Salmonella Reference Service, Public Health England (PHE) for the serotyping and phage typing of the isolates. The staff of the Genomics Service and Development Unit and the Bioinformatics Unit at PHE, for the sequencing of the isolates and initial data processing respectively. Sue Kidd, Salmonella Information and Liaison Officer for the APHA Epidemiology Workgroup for data provision. Daniel J Hicks and Julie Gough from Pathology APHA-Weybridge for laboratory support. The staff at the Scottish Microbiology Reference Laboratory, Glasgow Royal Infirmary, for laboratory support. We would like to thank Richard Elson and Natalie Adams for assistance with the geo-spatial analysis. This research was part-funded by Defra and the Welsh Government through the Animal & Plant Health Agency’s Diseases of Wildlife Scheme Scanning Surveillance Programme (Project ED1600), and through project WC 1027 from the Defra Strategic Evidence Fund; the Esmée Fairbairn Foundation; the Universities Federation for Animal Welfare, the Institute of Zoology and Public Health England. We would like to acknowledge the Gastrointestinal Disease Health Protection Research Unit for partial funding of the whole genome sequencing.
© 2018 The Author(s).