Epidemiology and Infection

Prevalence of Salmonella Typhimurium infection in Norwegian hedgehog populations associated with two human disease outbreaks

K.  HANDELAND  a1 c1, T.  REFSUM  a2, B. S.  JOHANSEN  a3, G.  HOLSTAD  a2, G.  KNUTSEN  a4, I.  SOLBERG  a5, J.  SCHULZE  a6 and G.  KAPPERUD  a7 a8
a1 Section of Wildlife Diseases, National Veterinary Institute Oslo, PO Box 8156 Dep, N-0033 Oslo, Norway
a2 Section of Bacteriology, National Veterinary Institute Oslo, PO Box 8156 Dep, N-0033 Oslo, Norway
a3 Stensåsveien 20B, N-4846 Arendal, Norway
a4 National Veterinary Institute Bergen, Bontelabo 8, N-5003 Bergen, Norway
a5 National Veterinary Institute Sandnes, PO Box 295, N-4303 Sandnes, Norway
a6 National Veterinary Institute Trondheim, Tungasletta 2, N-7485 Trondheim, Norway
a7 Division of Infectious Disease Control, Norwegian Institute of Public Health, N-0403 Oslo, Norway
a8 Section of Food Hygiene, The Norwegian School of Veterinary Science, PO Box 8146 Dep, N-0033 Oslo, Norway


Faecal carriage of salmonella was investigated in 320 hedgehogs from Moss municipality in south-eastern Norway, Askøy, Bergen and Os municipalities in central-western Norway, and five municipalities in south-western and central Norway. The sampling in Moss was carried out 1 year after a human outbreak of salmonellosis, whereas the sampling in Askøy, Bergen and Os was carried out during a human outbreak. Both outbreaks were caused by Salmonella Typhimurium 4,5,12[ratio]i[ratio]1,2. No salmonella were detected in the hedgehogs from south-western (0/115) and central (0/24) Norway. Thirty-nine percent (39/99) of the animals sampled on Jeløy, and 41% (34/82) of those from Askøy, Bergen and Os, carried S. Typhimurium 4,5,12[ratio]i[ratio]1,2. The PFGE profile of isolates from hedgehogs and human beings were identical within each of the two outbreak areas. A significantly higher carrier rate of S. Typhimurium occurred among hedgehogs sampled at feeding places, compared to those caught elsewhere. The salmonella-infected hedgehog populations most likely constituted the primary source of infection during both of the human disease outbreaks, and the Norwegian hedgehog is suggested as a reservoir host of S. Typhimurium 4,5,12[ratio]i[ratio]1,2.

(Accepted February 6 2002)

c1 Author for correspondence.