{'fraction_non_alphanumeric': 0.028716216216216218, 'fraction_numerical': 0.07305743243243243, 'mean_word_length': 4.878411910669975, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Yersiniosis in Poland in 2015 and 2016

OBJECTIVE
The aim of this study is to assess the epidemiological situation of yersiniosis in Poland in 2015 and 2016 in comparison to the previous years.


MATERIAL AND METHODS
The evaluation is based on analysis of data from the annual bulletins „Infectious diseases and poisoning in Poland” (4,5), information from individual yersiniosis case reports sent to the Department of Epidemiology of Infectious Diseases and Surveillance, NIPH-NIH by regional sanitaryepidemiological stations, information on outbreaks delivered by local sanitary-epidemiological stations through the system „Rejestr Ognisk Epidemicznych” (Electronic Registry of Epidemic Outbreaks) and data on deaths from the Department of Demographic Studies of the Central Statistical Office.


RESULTS
The number of registered yersiniosis cases in Poland in 2015 and 2016 was the same – 205 cases, corresponding to annual incidence of 0.53/100 000. Among them in 2015 there were 172 intestinal yersiniosis
cases and 33 extraintestinal yersiniosis cases and in 2016 – 167 intestinal yersiniosis cases and 38 extraintestinal yersiniosis cases. In 2015 and 2016 all intestinal yersiniosis cases met the criteria for confirmed case. In turn, among extraintestinal yersiniosis cases in 2015 26 cases met criteria for probable case and 7 for confirmed case and in 2016 – 32 for probable and 6 for confirmed case. Both in 2015 and in 2016 the incidence in mazowieckie voivodeship (1.61/100 000 in 2015 and 1.55/100 000 in 2016) largely exceeded the average incidence in Poland. The overall proportion of hospitalizations, 59.5% in 2015 and 58% in 2016, remained at the level similar to the preceding years. Serotype of the isolated Yersinia enterocolitica in 2015 in Poland was determined in 59 cases (32% of all Y. enterocolitica isolates). In 2016 serotype was determined in 47 cases of Y. enterocolitica infections (27% of all Y. enterocolitica isolates). Predominant serotype was O3. As in the previous years about 1/3 of infections occurred among children aged 0-4 (110 cases, 34.9% in 2015 and 92 cases, 30.9% in 2016). In 2015 there were no yersiniosis outbreaks, in 2016 there was one outbreak caused by Y. enterolitica.


CONCLUSION
Yersiniosis in Poland is rarely diagnosed and is likely underreported. The percentage of serotyped isolates continues to be low.