According to a study, its expansion across Spain and Europe is bringing infectious and parasitic diseases like rabies. This puts the health of native species and people at risk.
The raccoon spreads dangerous diseases as it invades Europe.
Credit: F.J. García
Originating in North America, the raccoon (Procyon lotor) is an invasive species that has established itself in Europe due to hunting and the fur trade along with its acquisition as a pet. In Spain, its presence in the wild is already commonplace in Madrid and Guadalajara and is sporadic in other regions such as the island of Mallorca. Its presence is however far from welcomed.
"Due to its rapid expansion and the long list of illnesses that it may carry, it poses a health risk that we must bear in mind," as outlined to SINC Beatriz Beltrán-Beck, the lead author of the study published in the 'European Journal of Wildlife Research' and researcher at the Research Institute of Hunting Resources (IREC, joint centre of the University of Castilla-La Mancha, the CSIC, and Castilla-La Mancha Council).
Bearing in mind that its population density could exceed 100 raccoons per km2, the success of the expansion of this small opportunistic carnivore is down to its ability to quickly adapt to different surroundings and omnivorous food habitats, its high reproductive potential and the absence of natural predators.
However, as Beltrán-Beck points out, "the impact that their expansion and invasion could have on the environment and the health of native species and humans is unknown." The researcher adds that the increase in population numbers and expansion to other countries and/or urban environments could increase the transmission of dangerous parasites and illnesses to domestic animals and humans.
The guest that nobody wants in their home
The research team gathered all types of information on the infectious and parasitic diseases that raccoons can transmit. The aim was to assess the propagation risk of infections along with possible control methods. But, according to the author, "there is little data in Europe on this species".
Rabies and a very pathogenic parasite to man (Baylisascaris procyonis), which was found in Germany, are some of the most significant illnesses found in the raccoon. But, along with bacterial illnesses, these are added to the West Nile virus which affects human, birds, horses and sheep.
Although in Western Europe rabies have been eliminated thanks to the oral vaccination for foxes (Vulpes vulpes), there is still concern that the raccoon could complicate the situation in some areas of Eastern Europe that are still home to rabies. In recent years 142 cases of rabies in raccoons have been identified, above all in Ukraine, Estonia, Germany and Lithuania.
This small American carnivore has been confirmed to be the host of the nematode worm Baylisascaris procyonis, which is responsible for Larva migrans, an illness caused by larval migration and parasite persistence under the skin, in the brain and in other organs. In the past this disease could only be found in America but is now emerging and on the rise in Europe.
"The infected raccoons can scatter millions of nematode B. procyonis eggs, which cause significant environmental contamination," warn the scientists. In the USA, between 68% and 82% of mammals have this parasite. Prevalence is also high in Germany although in Japan, for example, the parasite was not detected in any of the 1,688 raccoons captured for the purposes of other studies.
According to Beltrán-Beck, "more epidemiological studies are necessary on the current health situation and the implementation of measures that limit the possible impact of invading raccoons."
An unpleasant "pet"
Given its exotic origin and its rapid expansion since the 1970's, the raccoon is considered an invasive species in Europe. However, the majority of European countries, like Spain, do not control the trade of this animal, which is introduced onto the market as a pet.
"The case of Spain is a good example. The origin of its expansion is probably due to it escaping from the home where it was kept as a pet and due to the owners releasing it into the countryside when it reaches adulthood and becomes aggressive," adds the researcher.
According to the researcher, "this is mainly the case because there is a complete lack of knowledge of the biology, ecology, distribution and population density of the raccoon in Europe."
Beltrán-Beck B, García FJ, Gortázar C, (2012) "Raccoons in Europe: disease hazards due to the establishment of an invasive species", European Journal of Wildlife Research 58, pp 5
García JT, García FJ, Alda F, González JL, Aramburu MJ, Cortés Y, Prieto B, Pliego B, Pérez M, Herrera J, García-Román L, (2012) "Recent invasion and status of the raccoon (Procyon lotor) in Spain", Biological Invasions, DOI 10.1007/s10530-011-0157-x
SINC | EurekAlert!
Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel
Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)
University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.
Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.
Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...
In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
20.04.2018 | Physics and Astronomy
20.04.2018 | Interdisciplinary Research
20.04.2018 | Physics and Astronomy