The role of the wolf in endemic sylvatic Trichinella britovi infection in the Abruzzi region of Central Italy.

During the period 2004-2014 in the Abruzzi region (Central Italy), muscle samples gathered from hunted wild boars (n=16,323) and retrieved from carcasses of other susceptible wild mammals (n=838) and birds (n=438) were tested for Trichinella larvae according to European Union regulations. Although no positive samples were found from wild birds, 91 wild mammals tested positive. Six species were found to harbor Trichinella spp. infections, namely wolf (Canis lupus, 59 positive samples out of 218), red fox (Vulpes vulpes, 24/480), wild boar (Sus scrofa, 3/16,323), stone marten (Martes foina, 2/27), pine marten (Martes martes, 2/6) and wildcat (Felis silvestris, 1/8). All isolates tested for species attribution belonged to Trichinella britovi. The overall prevalence was 0.52% (IC 95%: 0.4-0.6). The higher frequency of positive samples in wolf, compared to red fox, was statistically significant (p=0.001). In spite of the limited geographical area of investigation and the random nature of sampling, this study provides new data on the circulation of T. britovi in Italy. In particular, the highest prevalence being found among wolves allows us to consider this species as a sentinel for T. britovi infection in the investigated area, and probably also in other apennine regions, which is different from the alpine regions where the red fox was reputed as the primary reservoir of Trichinella spp. infection.