Yersiniosis Epidemiology in New Zealand The vast majority of of yersiniosis in New Zealand are caused by Yersinia enterocolitica biotype 4 (commonly found in pigs in New Zealand). Y. enterocolitica biotype 3 (commonly found in cattle in New Zealand) and Y. pseudotuberculosis account for most of the remaining cases. More detailed epidemiological information is available on the Institute of Environmental Science and Research (ESR) surveillance website at www.surv.esr.cri.nz. Further information on foodborne illness is available at and . Case definition Clinical description In children under 5 years old, Y. enterocolitica infection typically causes diarrhoea, vomiting, fever and occasionally abdominal pain. In contrast, older children and adults are more likely to experience abdominal pain as the prominent symptom. Bacteraemia and sepsis may occur in immunocompromised individuals. Y. pseudotuberculosis is more likely to cause mesenteric adenitis and septicaemia than Y. enterocolitica. Laboratory test for diagnosis Laboratory confirmation requires at least one of the following: isolation of Yersinia enterocolitica or Y. pseudotuberculosis from or faeces detection of circulating antigen by ELISA or agglutination test. All isolates should be sent to the Enteric Reference Laboratory at ESR for further characterisation. Case classification investigation: A case that has been notified, but information is not yet available to classify it as probable or confirmed. A clinically compatible illness that is epidemiologically linked to a Probable: confirmed case or has had contact with the same common source that is, is part of – a common-source outbreak. Confirmed: A clinically compatible illness that is laboratory confirmed. Not a case: A case that has been investigated and subsequently found not to meet the case definition.
Yersiniosis Epidemiology in New Zealand The vast majority of of yersiniosis in New Zealand are caused by Yersinia enterocolitica biotype 4 (commonly found in pigs in New Zealand). Y. enterocolitica biotype 3 (commonly found in cattle in New Zealand) and Y. pseudotuberculosis account for most of the remaining cases. More detailed epidemiological information is available on the Institute of Environmental Science and Research (ESR) surveillance website at www.surv.esr.cri.nz. Further information on foodborne illness is available at and . Case definition Clinical description In children under 5 years old, Y. enterocolitica infection typically causes diarrhoea, vomiting, fever and occasionally abdominal pain. In contrast, older children and adults are more likely to experience abdominal pain as the prominent symptom. Bacteraemia and sepsis may occur in immunocompromised individuals. Y. pseudotuberculosis is more likely to cause mesenteric adenitis and septicaemia than Y. enterocolitica. Laboratory test for diagnosis Laboratory confirmation requires at least one of the following: isolation of Yersinia enterocolitica or Y. pseudotuberculosis from or faeces detection of circulating antigen by ELISA or agglutination test. All isolates should be sent to the Enteric Reference Laboratory at ESR for further characterisation. Case classification investigation: A case that has been notified, but information is not yet available to classify it as probable or confirmed. Probable: A clinically compatible illness that is epidemiologically linked to a confirmed case or has had contact with the same common source – that is, is part of a common-source outbreak. Confirmed: A clinically compatible illness that is laboratory confirmed. Not a case: A case that has been investigated and subsequently found not to meet the case definition.
communicable-disease-control-manual-2012.docx