Yersiniosis in Poland in 2011.

AIM: The aim of this study is to assess the epidemiology of yersiniosis in Poland in 2011 compared to previous years.

MATERIAL AND

METHODS

We reviewed surveillance data published in the annual bulletin "Infectious diseases and poisonings in Poland" from 2006 to 2011 (MP Czarkowski et al., NIH and GIS) and individual yersiniosis case reports from 2011 sent by the Sanitary-Epidemiological Stations. Additionally, we use data from the Department of Demographic Surveys in Central Statistical Office.

RESULTS

In Poland in 2011 a total of 257 yersiniosis cases were reported including 238 cases of intestinal and 19 cases of extraintestinal yersiniosis; 74% of patients were hospitalized. The incidence rate was 0.67 per 100,000 inhabitants. No deaths related to the disease were reported. The most affected group in intestinal infections were children younger than 4 (63% of all cases); symptoms usually involved diarrhea (87%), fever (76%), abdominal pain (47%) and vomiting (31%). Extraintestinal form of infection was less common than in 2010 (27 cases) and usually involved symptoms from the osteoarticular system, noted in 79% of patients (15 cases). Similarly to previous year (2010) most cases of yersiniosis were reported from Mazowieckie province (91), and the least from the Podlaskie province (1). Serological types of Yersinia enterocolitica were identified in 102 cases (39.7%): serotype O8 (56.8%), O3 (41%) and O9 (> 2%). There was one household outbreak involving 4 people.

CONCLUSIONS

Since 2006 in Poland in some areas of the country, occurrence of endemic infections caused by a type O8 is observed. A large percentage (60.3%) of unknown Yersinia serotypes is a consequence, that physicians do not always request serotyping. Additionally, the relatively low number of reported cases of extraintestinal yersiniosis in Poland may suggest underreporting, especially by rheumatological hospitals.