Dynamics of Echinococcus multilocularis infection in red fox populations with high and low prevalence of this parasite in Poland (2007–2014)

The aim of the study was to estimate the current prevalence of E. multilocularis in selected populations of red foxes in Poland and to evaluate the changes in prevalence of this parasite by comparison with the results obtained in the same area during earlier surveillance. The investigations were performed in the area of four Polish provinces: 2 eastern/south-eastern (Lubelskie and Podkarpackie) and 2 south-western (Śląskie and Opolskie). Five hundred red foxes coming from the investigated areas were examined between 2013 and 2014 to estimate the current situation in selected provinces. Moreover, 550 red foxes from the same areas examined between 2007 and 2013 were used for comparison of differences in E. multilocularis prevalences in time. Intestines were examined with the use of the sedimentation and counting technique. Among 500 foxes examined in the current study, 118 were positive for E. multilocularis. There were differences in prevalence between individual provinces: Podkarpackie Province - 54.6%, Lubelskie Province - 18.9%, Śląskie Province - 11.7%, and Opolskie Province - 3.9%. Statistical analysis demonstrated that in most cases there were no differences in prevalence between the current results and the results from previous studies. Only in Opolskie Province was a statistically significant increase observed between 2010 and 2014. A stable degree of infection in the region with high prevalence of this parasite was demonstrated. However, a significant increase in the region with very low prevalence of E. multilocularis points out the necessity to monitor this infection during the coming years to control the progress of the disease