Echinococcus in red foxes

The zoonotic dwarf fox tapeworm Echinococcus multilocularis has never been detected in mainland Norway.

The objective of the surveillance program is to document freedom of E. multilocularis (i.e. a prevalence below 1% at a confidence level of at least 95%) in mainland Norway.

Background

E. multilocularis is widespread in the northern hemisphere with endemic areas in the near Near East, Russia, China, Northern Japan and North America.

In Europe, the parasite was considered to be restricted to Central Europe i.e. Eastern France, southern Germany, parts of Switzerland and Austria until the 1990s. Yet, expansion in prevalence and geographic range into Northern, Eastern and Western Europe is ongoing and throughout the past three decades the parasite has been reported in 17 previously non-endemic countries in Europe.

In 1999, the parasite was detected for the first time on the archipelago of Svalbard. The first Danish case, a traffic-killed fox, was found in 2000, and in 2011, after 10 years of surveillance, the first positive fox was detected in Sweden.

Geographical spread of E. multilocularis is facilitated by migration and relocation of wild carnivores such as e.g. red foxes and wolfs (definitive hosts), introduction of infected rodents (intermediate hosts) and traffic of pet dogs.

EU legislation (998/2003/EC) governing preventive health measures for control of E. multilocularis allows member states claiming to be free of the parasite to require dogs to be treated against echinococcosis before being allowed to enter the country. Consequently, the Norwegian surveillance of E. multilocularis in red foxes was initiated in 2006.

2021

The prevalence of Echinococcus multilocularis was based on PCR analysis of faecal samples from 511 red foxes (Vulpes vulpes) collected during the licensed fox-hunting season in 2021 and 20 grey wolves (Canis lupus) killed in 2021. None of the samples tested positive for E. multilocularis, documenting that the prevalence in carnivore hosts (foxes and wolves) were below 1% at a confidence level of at least 95%.

Download report

Echinococcus in red foxes 2021 (pdf 2mb)

Previous reports

Echinococcus in red foxes 2020 (pdf 1mb)
Echinococcus in red foxes 2019 (pdf 2mb)
Echinococcus in red foxes 2018 (pdf 1007kb)
Echinococcus in red foxes 2017 (pdf 958kb)
Echinococcus in red foxes 2015 (pdf 1mb)
Echinococcus in red foxes 2014 (pdf 642kb)
Echinococcus in red foxes 2013 (pdf 1mb)
Echinococcus in red foxes 2012 (pdf 1mb)
Echinococcus in red foxes 2011 (pdf 1mb)
Echinococcus in red foxes 2009 (pdf 528kb)
Echinococcus in red foxes 2008 (pdf 525kb)
Echinococcus in red foxes 2007 (p. 109) (pdf 6mb)