Genetic diversity of the cestode Echinococcus multilocularis in red foxes at a continental scale in Europe.
BACKGROUND
Alveolar echinococcosis (AE) is a severe helminth disease affecting humans, which is caused by the fox tapeworm Echinococcus multilocularis. AE represents a serious public health issue in larger regions of China, Siberia, and other regions in Asia. In Europe, a significant increase in prevalence since the 1990s is not only affecting the historically documented endemic area north of the Alps but more recently also neighbouring regions previously not known to be endemic. The genetic diversity of the parasite population and respective distribution in Europe have now been investigated in view of generating a fine-tuned map of parasite variants occurring in Europe. This approach may serve as a model to study the parasite at a worldwide level.


RESULTS
The genetic diversity of E. multilocularis was assessed based upon the tandemly repeated microsatellite marker EmsB in association with matching fox host geographical positions. Our study demonstrated a higher genetic diversity in the endemic areas north of the Alps when compared to other areas.


CONCLUSIONS
The study of the spatial distribution of E. multilocularis in Europe, based on 32 genetic clusters, suggests that Europe can be considered as a unique global focus of E. multilocularis, which can be schematically drawn as a central core located in Switzerland and Jura Swabe flanked by neighbouring regions where the parasite exhibits a lower genetic diversity. The transmission of the parasite into peripheral regions is governed by a "mainland-island" system. Moreover, the presence of similar genetic profiles in both zones indicated a founder event.
Knapp
Jenny
J
Institute of Parasitology, Vetsuisse Faculty, University of Bern, Bern, Switzerland.
Bart
Jean-Mathieu
JM
Giraudoux
Patrick
P
Glowatzki
Marie-Louise
ML
Breyer
Isabelle
I
Raoul
Francis
F
Deplazes
Peter
P
Duscher
Georg
G
Martinek
Karel
K
Dubinsky
Pavol
P
Guislain
Marie-Hélène
MH
Cliquet
Florence
F
Romig
Thomas
T
Malczewski
Andrzej
A
Gottstein
Bruno
B
Piarroux
Renaud
R
D000818:Animals; D016000:Cluster Analysis; D016172:DNA Fingerprinting; D004443:Echinococcosis / Q000662:veterinary*; D048210:Echinococcus multilocularis / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D005060:Europe / Q000453:epidemiology; D005589:Foxes / Q000469:parasitology*; D014644:Genetic Variation; D005843:Geography; D018895:Microsatellite Repeats; D017720:Molecular Epidemiology