Muskrats are greater carriers of pathogenic Leptospira than coypus in ecosystems with temperate climates

Abstract

Knowledge on the possible sources of human leptospirosis, other than rats, is currently lacking. To assess the distribution pattern of exposure and infection by Leptospira serogroups in the two main semi-aquatic rodents of Western France, coypus (Myocastor coypus) and muskrats (Ondatra zibethicus), results of micro-agglutination testing and renal tissue PCR were used. In coypus, the apparent prevalence was 11% (n = 524, CI 95% = [9%-14%]), seroprevalence was 42% (n = 590, CI 95% = [38%-46%]), and the predominant serogroup was Australis (84%). In muskrats, the apparent prevalence was 33% (n = 274, CI 95% = [27%-39%]), seroprevalence was 57% (n = 305, CI 95% = [52%-63%]), and the predominant serogroup was Grippotyphosa (47%). Muskrats should therefore be considered an important source of Grippotyphosa infection in humans and domestic animals exposed in this part of France.

Exposure of Free-Ranging Wild Animals to Zoonotic Leptospira interrogans Sensu Stricto in Slovenia

“…Several researchers in Europe have presented information on antibodies to leptospiral serovars in nutria, ranging from 11.5% in Italy [80] to 76% in France [81] with the predominance of the Icterohaemorrhagiae serogroup. These results are consistent with the idea that nutria should be considered a risk factor for leptospirosis in humans and domestic animals and should be taken into account by public health decision makers, especially with regard to prevention and population control [79].…”

“…The coypu, also known as the nutria ( Myocastor coypus ), is a semiaquatic rodent and significant carrier of pathogenic Leptospira in Europe [ 79 ]. The current population size is unknown.…”

Aquatic invasive alien rodents in Western France: Where do we stand today after decades of control?

“…A strategy that should encourage decision makers and financers to fund the permanent control programme is to assess the direct or indirect costs related to the presence of AIAR in ecosystems [ 50 , 51 ]. One of the decisive arguments to convince local, federal, or national governmental authority is that AIAR are healthy carriers of significant diseases which are contagious to humans including leptospirosis, toxoplasmosis, and alveolar echinococcosis [ 24 ]. In France, about 600 cases of leptospirosis were confirmed in humans in 2014 for which 75% of cases were due to the use of wetlands through recreational-based water activities [ 52 ].…”

“…These two aquatic invasive alien rodents (AIAR) are widespread in Europe [ 19 – 21 ] and have been found across many wetlands in France [ 22 , 23 ]. On top of this, they are important carriers of diseases contagious to humans, including leptospirosis [ 24 ], toxoplasmosis [ 25 ] and alveolar echinococcosis [ 26 ], and livestock and pets, including leptospirosis, giant liver fluke and salmonellosis [ 24 , 27 ]. Both species dig burrows to shelter from climatic conditions and breed.…”

“…In France, despite the establishment of coypus’ and muskrats’ populations [ 24 , 38 ], few studies reporting the current management strategies for these species and their results at the national or regional level have been published, particularly since the 1990s [ 39 ]. Indeed, there is no national data on the number of coypus and muskrats that are trapped each year although a study in 2016 indicated that around 350 000 coypus and 70 000 muskrats were shot during the 2013–2014 game season in France [ 40 ].…”