Epidemiology and Infection

Original Papers


Increased risk for Campylobacter jejuni and C. coli infection of pet origin in dog owners and evidence for genetic association between strains causing infection in humans and their pets

L. MUGHINI GRASa1a2a3 c1, J. H. SMIDa2, J. A. WAGENAARa4a5a6, M. G. J. KOENEa5, A. H. HAVELAARa2a7, I. H. M. FRIESEMAa2, N. P. FRENCHa8, C. FLEMMINGa4, J. D. GALSONa9, C. GRAZIANIa1, L. BUSANIa1 and W. VAN PELTa2

a1 Department of Veterinary Public Health and Food Safety, Istituto Superiore di Sanità, Rome, Italy

a2 Centre for Infectious Disease Control, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands

a3 Department of Veterinary Medical Sciences, Bologna University, Italy

a4 Department of Infectious Diseases and Immunology, Utrecht University, The Netherlands

a5 Central Veterinary Institute of Wageningen UR, Lelystad, The Netherlands

a6 WHO Collaborating Centre for Reference and Research on Campylobacter/OIE Reference Laboratory for Campylobacteriosis, Utrecht/Lelystad, The Netherlands

a7 Institute for Risk Assessment Sciences, Utrecht University, The Netherlands

a8 Molecular Epidemiology and Public Health Laboratory, Massey University, Palmerston North, New Zealand

a9 Department of Zoology, Oxford University, UK


We compared Campylobacter jejuni/coli multilocus sequence types (STs) from pets (dogs/cats) and their owners and investigated risk factors for pet-associated human campylobacteriosis using a combined source-attribution and case-control analysis. In total, 132/687 pet stools were Campylobacter-positive, resulting in 499 strains isolated (320 C. upsaliensis/helveticus, 100 C. jejuni, 33 C. hyointestinalis/fetus, 10 C. lari, 4 C. coli, 32 unidentified). There were 737 human and 104 pet C. jejuni/coli strains assigned to 154 and 49 STs, respectively. Dog, particularly puppy, owners were at increased risk of infection with pet-associated STs. In 2/68 cases vs. 0·134/68 expected by chance, a pet and its owner were infected with an identical ST (ST45, ST658). Although common sources of infection and directionality of transmission between pets and humans were unknown, dog ownership significantly increased the risk for pet-associated human C. jejuni/coli infection and isolation of identical strains in humans and their pets occurred significantly more often than expected.

(Received September 22 2012)

(Revised December 17 2012)

(Accepted January 27 2013)

(Online publication February 28 2013)

Key words

  • Campylobacter;
  • case-control study;
  • domestic pets;
  • multilocus sequence typing;
  • source attribution