An outbreak of bovine tuberculosis in a fallow deer herd (Dama dama) in Sicily

Abstract

Wild ruminants have an important role in the epidemiology of bovine tuberculosis (bTB). This study describes an outbreak of bovine tuberculosis occurring in a fallow deer herd in Sicily. In 2012 a Sicilian herd of 47 animals was referred for cachexia. Pathological examination of 2 dead animals revealed disseminated granulomas predominantly involving the skin and subcutaneous tissues. Tissue samples were submitted for histological analysis, bacteriological culture, and biomolecular assay. PCR analysis identified Mycobacterium strains. Genotyping by spoligotyping and MIRU-VNTR profiles identified Mycobacterium bovis spoligotype SB0120 in both animals. In 2014, bTB skin testing of 28 fallow deer from the same group was positive in 4 and inconclusive in another 4. All 8 positive/inconclusive reactors were euthanized. Disseminated granulomatous lesions were noted in 6 of these animals, 3 of which (2 positive and 1 negative to skin tests) also presented cutaneous lesions. M. bovis spoligotype SB0120 was identified from all animals in which tuberculous-like lesions were observed, including 2 negative reactors. Many of the animals involved in this outbreak presented diffuse skin lesions, a potential route of transmission of M. bovis infection. Given the epidemiological role wildlife play in the maintenance of bTB infection and its potential risk for humans, a comprehensive monitoring plan for this zoonosis in wildlife species in Sicily is needed.

Molecular epidemiology of Mycobacterium tuberculosis complex strains isolated from livestock and wild animals in Italy suggests the need for a different eradication strategy for bovine tuberculosis

“…In this study, the spoligotype SB0942, never found before in Italy, was isolated in a wild boar. This isolation reveals the possibility that TB might also circulate in wildlife independently of what occurs in farm animals as already suggested from the previously reported isolate in fallow deer and wild boar (Amato et al., ).…”

“…Mycobacterium bovis and M. caprae strains were isolated in farmed animals (cattle, pigs and goats) (Table ), in a wild boar, but no isolates were obtained from buffalo and sheep. Single cases of M. bovis were also previously reported in fallow deer and wild boars (Amato et al., ). The human isolate included in this study was identified as M. bovis .…”

“…In this study, isolates from fallow deer and feral pigs (black Nebrodi pigs) describe in Amato et al (Amato et al, 2016) and Di Marco et al (Di Marco et al, 2012) were also considered.…”

“…Especially during the dry season, high animal density and transhumance increase the possibility of contact between susceptible species such as cattle and the autochthonous black Nebrodi pigs, which might act as reservoir of the infection (Di Marco et al., ). In this area, a case of bovine tuberculosis with generalized lesions in a fallow deer was caused by a strain of M. bovis with a spoligotype and MIRU‐VNTR profile identical to an isolate obtained from a wild boar of the same area, suggesting the spreading of the disease in wildlife (Amato et al., ). Molecular epidemiology is very useful, especially in those countries where the classical eradication programmes and movement restrictions are still in progress (Boniotti et al., ; Durr, Clifton‐Hadley, & Hewinson, ; Hauer et al., ).…”

“…The isolates were confirmed as members of the MBTC by acid alcohol-fast staining by the method described by Kulski et al (Kulski & Pryce, 1996), and by PCR restriction fragment length polymorphism (RFLP) analysis of the gyrB gene through RsaI and SacII restriction enzymes (Huard et al, 2003;Kasai, Ezaki, & Harayama, 2000;Niemann, Harmsen, Ru¨sch-Gerdes, & Richter, 2000). Isolates were mainly obtained from farm animals (cattle and pigs), but some isolates from wildlife were available (fallow deer (Amato et al, 2016) and wild boars) (Tables 2 and 3), were also included in this study. A M. bovis isolate was obtained from a person, the owner of a TB infected herd, who showed suspected clinical symptoms (pneumonia).…”