Maas M, Mulder J, Montizaan M, Dam-Deisz WDC, Jaarsma RI, Takumi K, van Roon A, Franssen FFJ, van der Giessen JWB
RIVM Report 2017-0200
Sightings of raccoon dogs and raccoon occur more frequently the last decade, especially in the eastern part of the Netherlands. New species like these can (re-)introduce pathogens or change the epidemiology of endemic pathogens. For example, raccoon dogs are known to roam long distances and can live in a variety of habitats, facilitating spread of pathogens.
Both raccoon dogs and raccoons can carry infectious pathogens that can cause disease in humans. In a study performed in 2014-2015, one out of nine raccoon dogs tested positive for Trichinella spiralis and one for Echinococcus multilocularis. Two raccoons, found dead in 2014 in the area of Doetinchem, tested positive for Baylisascaris procyonis. Therefore, the RIVM examined in 2016-2017 12 raccoon dogs and five raccoons to gain insight in the occurrence of various pathogens: Echinococcus multilocularis (fox tapeworm), Trichinella spp. and Francisella tularensis in raccoon dogs and Baylisascaris procyonis in raccoons.
The fox tapeworm, Trichinella spp. and Francisella tularensis were not detected. Baylisascaris procyonis was found in one raccoon. This raccoon originated from Limburg. It is unclear whether the raccoons that are seen in the Netherlands originate from wild populations, or whether they are released or escaped pet animals. Therefore, it is difficult to make statements about the finding of Baylisascaris procyonis in Limburg.
Baylisascaris procyonis eggs are spread in the environment by infected raccoons through the feces. The eggs can survive for long periods in the environment. When humans ingest these eggs, larvae develop that can spread through the body, including the brain where they can cause neurologic symptoms. This chance seems currently small, but insight in the spread of infected raccoons is important for a good risk-assessment.