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Rodents are the primary reservoirs for pathogenic Leptospira species, which cause leptospirosis. Among the key potential carriers are water voles, whose population outbreaks can consequently pose a major threat to human and animal health. We studied the prevalence, prominence, and epidemiology of pathogenic Leptospira species in water voles in central France. First, 46 voles were captured, and DNA was extracted from kidney, lung, liver, blood, and urine and tested for the presence of Leptospira using three molecular methods: PCR, O-antigen typing, and variable number tandem repeat (VNTR) typing. We also attempted to culture leptospires from kidney and urine samples. In addition, we investigated leptospiral antibodies in serum samples from 60 sheep using microscopic agglutination testing. These animals co-occurred with the voles, so we sought to assess their degree of exposure and involvement in pathogen dynamics. The overall prevalence of infection was 76.1% (CI95% [61.2%, 87.4%]). The only strain found was L. kirschneri serogroup Grippotyphosa and a similar VNTR profile was acquired. Leptospires were successfully cultured from kidney and urine samples for four voles. Three sheep had low antibody titers against the Leptospira serogroup Grippotyphosa. Taken together, our results suggest the exclusive carriage of L. kirschneri serogroup Grippotyphosa among water voles in central France. Nevertheless, their ability to act as reservoir hosts that transmit the pathogen to co-occurring livestock remains unclear and merits further research.

Rodent management involves the use of anticoagulant rodenticides (ARs). This use has resulted in the selection of numerous resistance alleles in the Vkorc1 gene, encoding the target enzyme of ARs. In Africa, although rodents are a major problem as a consequence of their transport and transmission of zoonotic pathogens, and damage to crops, the use of ARs and the spread of resistance alleles are poorly documented. We attempted to address both issues in Chad which is one of the largest countries in Africa. Owing to its location at the crossroads of central and northern Africa, Chad is representative of many African countries. Methods: Using a sampling of nearly 300 rodents composed of invasive and endemic rodents collected in six of Chad's largest cities, exposure to ARs was analyzed by their quantification in the liver; the spread of AR resistance alleles was analyzed by Vkorc1 sequencing. Results: We demonstrate the use of both ARs generations in Chadian cities and report the total sequencing of the Vkorc1 for 44 Mastomys natalensis with detection of two different haplotypes, the sequencing of the Vkorc1 for two other endemic rodent species, M. kollmannspergeri and Arvicanthis niloticus, and finally the detection of three new missense mutations – V29E, V69E and D127V – in R. rattus, potentially associated with resistance to ARs. Discussion: These results should argue for the implementation of a reasoned management of rodent populations in Africa to avoid the spread of ARs resistance alleles. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]