Caseous Lymphadenitis Caused by Corynebacterium pseudotuberculosis in Alpine Chamois (Rupicapra r. rupicapra): a Review of 98 Cases.

Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis (CLA) in domestic and wild ruminants. Here we describe CLA in alpine chamois (Rupicapra r. rupicapra) based on a series of 98 cases of C. pseudotuberculosis infection confirmed by bacteriology and gene sequence analysis. The population included 53 males and 45 females distributed within three age groups: up to 18 months (n = 14), 18 months to 4 years (n = 11) and over 4 years (n = 73). Four different gross lesion distribution patterns, observed individually or variably combined in the same animal, were defined: (1) cutaneous/external (i.e. subcutaneous lymph nodes with or without muscle involvement, n = 34); (2) abdominal visceral (i.e. only abdominal organs involved: liver and/or spleen and/or kidney and/or lymph nodes, n = 35); (3) thoracic visceral (i.e. only thoracic organs involved: lung and/or heart and/or lymph nodes, n = 26); and (4) generalized visceral (i.e. abdominal and thoracic organs involved, n = 26). In six particularly severe cases, mammary gland, testis, vertebral bone and the central nervous system were also affected. Macroscopically, most abscesses were characterized by fluid pus, confirmed by microscopy that showed the absence of distinct concentric layers and coagulative necrosis, which are typically seen in sheep and goats raised in areas where the infection is endemic. In three cases amyloid deposits were observed in the liver and kidney. The C. pseudotuberculosis strains isolated were highly homologous to the reference strain ATCC 19410, except for some variability in their ability to ferment maltose and mannitol. Based on the production of nitrate reductase, 95 strains were attributed to the ovis biovar (nitrate reduction negative) and three to the equi biovar (nitrate reduction positive). All strains were sensitive to antibiotics, except to ampicillin (62.3% resistant strains) and gentamicin (83.7% resistant strains). Using an indirect enzyme-linked immunosorbent assay designed for CLA in sheep and goats, seven (58.3%) of 12 serum samples tested positive for antibodies.

Serological and virological survey of hepatitis E virus in wild boar populations in northwestern Italy: detection of HEV subtypes 3e and 3f.

Although rare in developed countries, most acquired human cases of hepatitis E virus (HEV) infection are associated with travel to developing countries where HEV is endemic. Increasingly, however, sporadic, non-travel-related HEV cases have been reported in developed countries. In Italy, only two studies to date have investigated the presence of HEV in wild boars. Here, we report a serological and virological survey of HEV in wild boar populations in northwestern Italy. During the hunting season, 594 serum and 320 liver samples were collected and screened for antibodies to HEV and HEV RNA. Overall, the seroprevalence was 4.9 %, and HEV RNA was detected in 12 liver samples (p = 3.7 %). No serum samples tested positive for HEV RNA. Phylogenetic analysis of the ORF2 region revealed that the isolates clustered within genotype 3, subtypes 3e and 3f, and were closely related to HEV strains previously detected in domestic pigs farmed in the same geographic area. Although the routes of viral transmission are still poorly understood, our data show that HEV genotypes 3e and 3f circulate in wild boars in northwestern Italy. Also, they provide evidence that autochthonous HEV infections in Italy could also be linked to wild boar populations, suggesting an increased risk for domestically acquired HEV infection in humans through wild animals. The HEV sequences determined in this study may be useful for comparing present and future human isolates to identify transmission events between wild boar, humans, and farmed pigs. Similarly to other more commonly known zoonotic agents, HEV should be included in national or regional disease surveillance programs for wild animals.