Duck Liver–associated Outbreak of Campylobacteriosis among Humans, United Kingdom, 2011

Muhammad Abid, Helen Wimalarathna, Janette Mills, Luisa Saldana, Winnie Pang, Judith F. Richardson, Martin C. J. Maiden, and Noel D. McCarthy

Author affiliations: Public Health England, Chilton, UK (M. Abid, J. Mills, L. Saldana, J.F. Richardson, N.D. McCarthy); University of Oxford, Oxford, UK (H. Wimalarathna, M.C.J. Maiden, N.D. McCarthy); Reading Borough Council, Reading, UK (W. Pang)

Abstract

Campylobacter spp.–related gastroenteritis in diners at a catering college restaurant was associated with consumption of duck liver pâté. Population genetic analysis indicated that isolates from duck samples were typical of isolates from farmed poultry. Campylobacter spp. contamination of duck liver may present a hazard similar to the increasingly recognized contamination of chicken liver.

Although bacteria in the genus Campylobacter commonly cause gastroenteritis, identified outbreaks are relatively rare. In England and Wales, 21 identified campylobacteriosis outbreaks during 1992–1994 (1) and 50 during 1995–1999 (2) accounted for 0.2% and 0.4% of reported outbreaks of gastroenteritis, respectively. Water and milk were the main sources of Campylobacter spp. outbreaks in the United Kingdom and the United States, although becoming less so (2,3). Poultry consumption and restaurant dining are the most common foodborne illness risks, although many foodstuffs are implicated (2,3). Outbreaks associated with chicken liver pâté or parfait have increased: 14 outbreaks were associated with these items in England and Wales during 2007–2009 compared with 11 during the 15 preceding years (4). There were also large outbreaks in Scotland (5,6). The peer-reviewed literature identifies chicken as the type of poultry liver or refers to poultry without specifying type.
Multilocus sequence typing is increasingly used to identify animal origins of human campylobacteriosis (7). The presence of multiple Campylobacter strains (6) in individual outbreaks linked to chicken liver is consistent with documentation that chickens harbor multiple strains (8), that pâté is prepared from multiple livers (5,6), or both. We describe epidemiologic evidence for a duck liver pâté–associated outbreak and compare sequence types (STs) of isolates with animal and food isolate datasets.