Echinococcus multilocularisinfections of rural, residential and urban foxes (Vulpes vulpes) in the canton of Geneva, Switzerland

Abstract

Summary : SWe examined 267 red foxes (Vulpes vulpes) from the canton of Geneva, Switzerland, for intestinal infections with Echinococcus multilocularis. This region is situated in the core area of the endemic range of this zoonotic cestode in Central Europe. Several factors were taken into account and urbanisation level appeared to be the most explicative to describe observed differences. The prevalence decreased significantly from rural and residential areas (prevalence of 52 %, CI 43-62 %, and 49 %, CI 38-59 %, respectively) to the urban area (prevalence of 31 %, CI 19-42 %). A few juvenile foxes harboured very high burdens up to more than 120,000 worms and were significantly more heavily infected than adults. The intensity of infection decreased from rural and residential areas to the city, suggesting a lower contamination of the urban environment. Résumé

Infection of foxes byEchinococcocus multilocularisin urban and suburban areas of Nancy, France: influence of feeding habits and environment

“…The same trend was observed in Switzerland: Zürich (Hegglin et al, 2007;Hofer et al, 2000) and Geneva (Fischer et al, 2005). The first report of an urban cycle for E. multilocularis concerned the city of Zürich.…”

“…In Europe, the red fox is the main source of environmental contamination (Deplazes & Eckert, 2001). Recent studies have shown the presence of E. multilocularis in red fox in various cities: Copenhagen (Kapel & Saeed, 2000), Geneva (Fischer et al, 2005), Prague (Martinek et al, 2000), Stuttgart (Romig et al, 1999), Zürich (Hofer et al, 2000) in Europe, Sapporo (Tsukada et al, 2000) and Otaru (Yimam et al, 2002) in Japan. The prevalence among urban foxes was lower than among suburban or rural foxes.…”

Rodents as shared indicators for zoonotic parasites of carnivores in urban environments

“…Therefore, the environmental contamination by infectious free-living stages, and thereafter the infection pressure by these parasites, is likely to differ and depend on the distribution, abundance and habitat use of the respective definitive hosts, notably in urbanized areas. High prevalences of infection with T. canis in domestic dogs and red foxes in urban areas (O'Lorcain, 1994 ;Habluetzel et al 2003 ;Reperant et al 2007), and high prevalences of infection with E. multilocularis in red foxes in peri-urban areas (Hofer et al 2000 ;Fischer et al 2005 ;Robardet et al 2008) have notably been reported, suggesting high levels of environmental contamination in these environments.…”

“…This conurbation is densely populated with 400 000 inhabitants living in an area of 240 km 2 . The study area was subdivided into three zones of increasing level of urbanization according to human density, as described by Fischer et al (2005).…”

A stochastic model of Echinococcus multilocularis transmission in Hokkaido, Japan, focusing on the infection process

“…Although little is known about how protoscoleces propagate within infected voles, we assume that the number of protoscoleces in voles increases exponentially after a latent period, that the rate of increase declines because of the environmental capacity, and that the number of protoscoleces is eventually saturated. We consider an immune structure in the model based on dissection data showing that juvenile foxes have significantly greater worm burdens than adult foxes (Hofer et al, 2000;Fischer et al, 2005).…”