Serological Investigation of Wild Boars (Sus scrofa) and Red Foxes (Vulpes vulpes) As Indicator Animals for Circulation ofFrancisella tularensisin Germany

Abstract

Tularemia outbreaks in humans have recently been reported in many European countries, but data on the occurrence in the animal population are scarce. In North America, seroconversion of omnivores and carnivores was used as indicator for the presence of tularemia, for the European fauna, however, data are barely available. Therefore, the suitability of wild boars (Sus scrofa) and red foxes (Vulpes vulpes) as indicators for the circulation of F. tularensis in Germany was evaluated. Serum samples from 566 wild boars and 457 red foxes were collected between 1995 and 2012 in three federal states in Central Germany (Hesse, Saxony-Anhalt, and Thuringia). The overall rate of seropositive animals was 1.1% in wild boars and 7.4% in red foxes. In conclusion, serological examination of red foxes is recommended, because they can be reliably used as indicator animals for the presence of F. tularensis in the environment.

Detection of Coxiella burnetii and Francisella tularensis in Tissues of Wild-living Animals and in Ticks of North-west Poland

“…In this study any characteristic sequences were detected in testing for the presence of F. tularensis DNA in wild-living animals. Despite a large proportion of positive results obtained in ELISA by others: 3.5% (Al Dahouk et al 2005), 7.5% (Kuehn et al 2013), 7.4% (Otto et al 2014) or even 15-30% (Taussing and Landau 2008), in this study the biological agent remains undetected in animal tissues.…”

High and novel genetic diversity ofFrancisella tularensisin Germany and indication of environmental persistence

“…The markers included in the analysis have been described previously: B.1-B. 14 [29]. Newly identified clades were named according to this canSNP classification system for F. tularensis that to date, in addition to the 43 canSNPs used above by canSNPer, also include the subspecies holarctica canSNPs B.67-B.68 [30], and B.69-B.70 [31].…”

“…In recent years, both multiple tularemia outbreaks and single human cases have been reported from almost the entire area of Germany, and tularemia is now considered a re-emerging zoonotic disease. The knowledge about human clinical cases as well as seroprevalence in humans has increased in recent years [9][10][11][12][13][14]. Indeed, an unexpectedly high rate (7•5%) of wild animals seropositive for F. tularensis was detected in the Berlin/Brandenburg region [15] and in other regions of Germany [12][13][14].…”

Francisella tularensisin Swedish predators and scavengers

“…Antibodies against F. tularensis have been detected in wild animals (red fox, wild boar and raccoon dog) that did not show signs of disease in Austria [9], the Czech Republic [10] and Germany [11, 12]. The animal species investigated in these studies, had seroprevalences varying between 6.4 and 7.9% and were considered as good sentinels.…”