Detection and Characterization of a Novel Porcine Teschovirus in Wild Boars (Sus scrofa) in France

Porcine teschoviruses (PTV) are enteric pathogens affecting suids. Although ubiquitous in healthy domestic pig (Sus scrofa domesticus) populations, some virulent strains can cause severe neurological disorders known as Teschen-Talfan disease. Wild boars (Sus scrofa) can host PTV, but little is known about their epidemiological role in the dynamic of the pathogens. Until recently, PTV had not been reported in wild boars in France. However, in 2019 and 2020, serological evidence of PTV infection was detected in hunted wild boars from Drôme and Marne, some of which exhibited neurological and reproductive disorders. As a result, a combined serological, virological, and phylogenic screening was implemented. Results revealed high seroprevalence rates, up to 38%, suggesting endemic circulation of PTV in these populations. Genetic sequencing of PCR-positive samples suggests the presence of a novel PTV genotype. These findings raise questions about the pathogenicity of this new PTV strain as well as of the potential role of wild boars in the epidemiology of PTV in France, and highlight the need for further investigation into the interactions between domestic pigs and wild boar and the dynamics of the spread of PTV between them.