EN
The paper describes the variability of the NADH dehydrogenase sequences of Echinococcus multilocularis from 4 fox isolates in Poland, in comparison with the previously described genetic variants of this species. Polish isolate was more similar to the isolate from Japan than to the genetic variants M1 and М2, both of which are found in Europe. The level of variability observed within ND1 sequences of E. multilocularis, is comparable with the variability reported for some pairs of most similar strains of E. granulosus (G1/G2, G2/G3, G1/G3, G6/G7).