Descriptive epidemiology of Yersinia enterocolitica infection in a high-incidence area over an 8-year period, 2006–2013. EDICS project

Abstract Descriptive epidemiology of Yersinia enterocolitica infection in an area of Castellon (Spain) between 2006 and 2013 from Yersinia enterocolitica strains isolated in the area and confirmed by the Spanish national reference laboratory. There were a total of 144 cases. The estimated incidence was 9.7 cases per 105 person-year. The age group most affected was 0–4 years (rate 110.3 per 105 p-y), with a maximum in infants aged 6–11 months of age (190.4 per 105 p-y). The average duration of the disease was 15.5 days. 7% of the patients were hospitalised. Only 2 outbreaks of a family nature related to the consumption of pork were detected. The temporal evolution reflects higher incidence during the winter season (January). The most common exposure factor among the cases was the consumption of dried pork sausage (50% of the cases interviewed). The 58 typed strains were all of the biotype 4, serotype O:3, except one O:9. We distinguished 21 pulsotypes grouped in 8 clusters with a similarity of 97%. Over a number of years, a substitution of some pulsotypes for others was observed. Yersiniosis has a high incidence in our area, with a clear seasonality of winter predominance. It affects very young children, in particular. The strains are of the same serotype, but the variety of pulsotypes changed over time. As an exposure factor for further analytical studies, the consumption of some pork products is proposed, without ruling out other factors.