Mycobacteria fecal shedding in wild boars (Sus scrofa), South-eastern France

Abstract

The recent recrudescence of tuberculosis in cattle has implicated wild boar as a reservoir and vector of this disease, which led to the investigation of fecal shedding of the causative Mycobacterium bovis. In the Provence region of France, wild boars are very abundant, and the current study was carried out to assess the presence of tuberculous and nontuberculous mycobacteria in feces of wild boar population. W e developed an original protocol allowing the fast isolation of mycobacteria by combining a 1%-chlorhexidine decontamination of fecal matter with culture on MOD9 medium. Colonies were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, combined with DNA sequencing. This protocol yielded no tuberculous mycobacteria among ninety-nine wild boar fecal samples collected in the Provence region. However, non-tuberculous mycobacteria were isolated from five samples (5.05%), including Mycobacterium peregrinum, Mycobacterium vaccae and Mycobacterium setense, the last species being previously unreported in the wild boar; in addition to two positive samples for Nocardia spp. In conclusion, wild boars in southeastern France are not shedding tuberculosis agents, but they could constitute a reservoir of human non-tuberculous mycobacteriosis in selected populations directly exposed to wild boars.