Evidence of the role of European wild boar as a reservoir of Mycobacterium tuberculosis complex

Bovine tuberculosis (bTB) is caused by Mycobacterium bovis and closely related mycobacteria of the Mycobacterium tuberculosis complex. They have an extensive host range and may cause zoonotic TB. A major obstacle to bTB eradication in livestock is the implication of wildlife in the natural cycle of the pathogen. The identification of wildlife reservoir hosts is crucial for the implementation of effective control measures. The European wild boar (Sus scrofa) is frequently considered a spillover or dead end host rather than a true reservoir, and scientific evidence is conflicting outside Mediterranean Spain. The aim of this review is to update current scientific evidence of the wild boar as a TB reservoir and to underline those aspects that need further research. Evidences supporting that wild boar is a TB reservoir host include: (i) presence of common M. tuberculosis complex genotypes in wild boar, domestic and wild animals and humans, (ii) high prevalence of M. bovis among wild boar in estates fenced for decades in complete absence of contact with domestic livestock, and other wild ungulates (iii) TB lesions are frequently seen in thoracic lymph nodes and lungs, suggesting that respiratory infection and excretion may occur, and (iv) extensive tuberculous lesions in more than one anatomical region occur in a high proportion of juvenile wild boar that probably represents the main source of mycobacterial excretion. Hence, epidemiological, pathological and microbiological evidence strongly suggests that, at least in Spanish Mediterranean ecosystems, wild boar are able to maintain TB infection in the wild and are most probably able to transmit the disease to other species, acting as a true wildlife reservoir. These results expand the list of wildlife species that act as natural reservoirs of TB in different parts of the world and suggest the need to control the infection in wild boar populations for the complete eradication of the disease in Spain.     

Spatiotemporal interactions between wild boar and cattle: implications for cross-species disease transmission

Controlling infectious diseases at the wildlife/livestock interface is often difficult because the ecological processes driving transmission between wildlife reservoirs and sympatric livestock populations are poorly understood. Thus, assessing how animals use their environment and how this affects interspecific interactions is an important factor in determining the local risk for disease transmission and maintenance. We used data from concurrently monitored GPS-collared domestic cattle and wild boar (Sus scrofa) to assess spatiotemporal interactions and associated implications for bovine tuberculosis (TB) transmission in a complex ecological and epidemiological system, Doñana National Park (DNP, South Spain). We found that fine-scale spatial overlap of cattle and wild boar was seasonally high in some habitats. In general, spatial interactions between the two species were highest in the marsh-shrub ecotone and at permanent water sources, whereas shrub-woodlands and seasonal grass-marshlands were areas with lower predicted relative interactions. Wild boar and cattle generally used different resources during winter and spring in DNP. Conversely, limited differences in resource selection during summer and autumn, when food and water availability were limiting, resulted in negligible spatial segregation and thus probably high encounter rates. The spatial gradient in potential overlap between the two species across DNP corresponded well with the spatial variation in the observed incidence of TB in cattle and prevalence of TB in wild boar. We suggest that the marsh-shrub ecotone and permanent water sources act as important points of TB transmission in our system, particularly during summer and autumn. Targeted management actions are suggested to reduce potential interactions between cattle and wild boar in order to prevent disease transmission and design effective control strategies.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-014-0122-7) contains supplementary material, which is available to authorized users.     

Evaluation of ELISA coupled with Western blot as a surveillance tool for Trichinella infection in wild boar (Sus scrofa)

Trichinella surveillance in wildlife relies on muscle digestion of large samples which are logistically difficult to store and transport in remote and tropical regions as well as labour-intensive to process. Serological methods such as enzyme-linked immunosorbent assays (ELISAs) offer rapid, cost-effective alternatives for surveillance but should be paired with additional tests because of the high false-positive rates encountered in wildlife. We investigated the utility of ELISAs coupled with Western blot (WB) in providing evidence of Trichinella exposure or infection in wild boar. Serum samples were collected from 673 wild boar from a high- and low-risk region for Trichinella introduction within mainland Australia, which is considered Trichinella-free. Sera were examined using both an ‘in-house’ and a commercially available indirect-ELISA that used excretory–secretory (E/S) antigens. Cut-off values for positive results were determined using sera from the low-risk population. All wild boar from the high-risk region (352) and 139/321 (43.3%) of the wild boar from the low-risk region were tested by artificial digestion. Testing by Western blot using E/S antigens, and a Trichinella-specific real-time PCR was also carried out on all ELISA-positive samples. The two ELISAs correctly classified all positive controls as well as one naturally infected wild boar from Gabba Island in the Torres Strait. In both the high- and low-risk populations, the ELISA results showed substantial agreement (k-value = 0.66) that increased to very good (k-value = 0.82) when WB-positive only samples were compared. The results of testing sera collected from the Australian mainland showed the Trichinella seroprevalence was 3.5% (95% C.I. 0.0–8.0) and 2.3% (95% C.I. 0.0–5.6) using the in-house and commercial ELISA coupled with WB respectively. These estimates were significantly higher (P < 0.05) than the artificial digestion estimate of 0.0% (95% C.I. 0.0–1.1). Real-time PCR testing of muscle from seropositive animals did not detect Trichinella DNA in any mainland animals, but did reveal the presence of a second larvae-positive wild boar on Gabba Island, supporting its utility as an alternative, highly sensitive method in muscle examination. The serology results suggest Australian wildlife may have been exposed to Trichinella parasites. However, because of the possibility of non-specific reactions with other parasitic infections, more work using well-defined cohorts of positive and negative samples is required. Even if the specificity of the ELISAs is proven to be low, their ability to correctly classify the small number of true positive sera in this study indicates utility in screening wild boar populations for reactive sera which can be followed up with additional testing.     

Towards harmonised procedures in wildlife epidemiological investigations: A serosurvey of infection with Mycobacterium bovis and closely related agents in wild boar (Sus scrofa) in Switzerland

Bovine tuberculosis (bTB) is a (re-)emerging disease in European countries, including Switzerland. This study assesses the seroprevalence of infection with Mycobacterium bovis and closely related agents in wild boar (Sus scrofa) in Switzerland, because wild boar are potential maintenance hosts of these pathogens. The study employs harmonised laboratory methods to facilitate comparison with the situation in other countries. Eighteen out of 743 blood samples tested seropositive (2.4%, CI: 1.5–3.9%) by ELISA, and the results for 61 animals previously assessed using culture and PCR indicated that this serological test was not 100% specific for M. bovis, cross-reacting with M. microti. Nevertheless, serology appears to be an appropriate test methodology in the harmonisation of wild boar testing throughout Europe. In accordance with previous findings, the low seroprevalence found in wild boar suggests wildlife is an unlikely source of the M. bovis infections recently detected in cattle in Switzerland. This finding contrasts with the epidemiological situation pertaining in southern Spain.     

Antibody response to Raboral VR-G® oral rabies vaccine in captive and free-ranging black-backed jackals (Canis mesomelas)

Rabies is a zoonotic disease that remains endemic in large parts of southern Africa because of its persistence in wildlife and domestic dog vectors. The black-backed jackals (Canis mesomelas) is primarily the wildlife vector responsible for rabies outbreaks in northern parts of South Africa. Two trials were carried out to investigate antibody responses to the oral rabies vaccine Raboral V-RG® in black-backed jackals under captive and free-ranging conditions. In captive jackals 10/12 (83%; 95% confidence interval [CI]: 52% – 98%), seroconverted after single oral vaccination. Nine captive jackals had protective antibody titres (> 0.5 IU/mL) at 4 weeks (median: 2.1 IU/mL; inter quartile range [IQR]: 0.6–5.7) and 10 jackals had at 12 weeks (median: 3.5 IU/mL; IQR: 1.5–8.3) and three maintained antibody titres for up to 48 weeks (median: 3.4 IU/mL; IQR: 2.0–6.3). Four sites were baited with Raboral V-RG® vaccine for wild jackals, using fishmeal polymer and chicken heads. Baits were distributed by hand or from vehicle at three sites in north-eastern South Africa, with an average baiting density of 4.4 baits/km² and at one site in central South Africa, at 0.12 baits/km². This resulted in protective antibody titres in 3/11 jackals (27%; 95% Cl: 6–61) trapped between 3 and 12 months after baiting in north-eastern South Africa, compared with 4/7 jackals (57%; 95% Cl: 18–90) trapped after 3–18 months in central South Africa. This study shows the potential utility of oral rabies vaccination for the control of wildlife-associated rabies in north-eastern and central South Africa, but extensive studies with wider distribution of bait are needed to assess its potential impact on rabies control in wild jackals.     

Molecular characterization of Mycobacterium tuberculosis complex isolates from wild ungulates in south-central Spain

The role of European wild ungulates in the epidemiology of tuberculosis (TB) is still under discussion. This study describes the geographical distribution and molecular typing of 77 Mycobacterium tuberculosis complex isolates belonging either to M. bovis or to M. caprae, cultivated from hunter harvested red deer (Cervus elaphus) and European wild boar (Sus scrofa) in 24 Spanish localities, and compares them with spoligotypes detected previously in humans, livestock or wild animals, as described in the literature. The distribution of the molecular type patterns suggests that the population of M. tuberculosis complex strains isolated from Spanish wild ungulates is spatially structured despite the lack of important geographical barriers and despite the increasingly frequent wildlife translocations. Red deer and the European wild boar can share the same molecular types in localities in which the M. tuberculosis complex was isolated from both species. Strains of bovine and caprine origin do circulate in the same local wildlife populations. Six out of 11 spoligotypes were similar to types described in human cases. The isolation of TB strains in fenced estates from wild animals that have not had contact with domestic livestock for at least the past two decades, strongly suggests that the M. tuberculosis complex is able to survive in these populations. Therefore, wildlife including cervids and the wild boar need to be considered in the epidemiology and control of tuberculosis.     

Improved detection of Mycobacterium tuberculosis and M. bovis in African wildlife samples using cationic peptide decontamination and mycobacterial culture supplementation

In South Africa, mycobacterial culture is regarded as the gold standard for the detection of Mycobacterium tuberculosis complex (MTBC) infection in wildlife even though it is regarded as “imperfect.” We compared a novel decontamination and mycobacterial culture technique (TiKa) to the conventional mycobacterium growth indicator tube (MGIT) system using known amounts of bacilli and clinical samples from MTBC-infected African buffaloes (Syncerus caffer), white rhinoceros (Ceratotherium simum), and African elephants (Loxodonta africana). Use of the TiKa-KiC decontamination agent on samples spiked with 10,000 to 10 colony forming units (cfu) of M. bovis (SB0121) and M. tuberculosis (H37Rv) had no effect on isolate recovery in culture. In contrast, decontamination with MGIT MycoPrep resulted in no growth of M. bovis samples at concentrations < 1,000 cfu and M. tuberculosis samples < 100 cfu. Subsequently, we used the TiKa system with stored clinical samples (various lymphatic tissues) collected from wildlife and paucibacillary bronchoalveolar lavage fluid, trunk washes, and endotracheal tube washes from 3 species with known MTBC infections. Overall, MTBC recovery by culture was improved significantly (p < 0.01) by using TiKa compared to conventional MGIT, with 54 of 57 positive specimens versus 25 of 57 positive specimens, respectively. The TiKa mycobacterial growth system appears to significantly enhance the recovery of MTBC members from tissue and paucibacillary respiratory samples collected from African buffaloes, African elephants, and white rhinoceros. Moreover, the TiKa system may improve success of MTBC culture from various sample types previously deemed unculturable from other species.     

Tuberculosis vaccination sequence effect on protection in wild boar

The Eurasian wild boar (Sus scrofa) is a reservoir for tuberculosis (TB) in which vaccination is a valuable tool for control. We evaluated the protection and immune response achieved by homologous and heterologous regimes administering BCG and heat-inactivated Mycobacterium bovis (IV). Twenty-one wild boar piglets were randomly allocated in five groups: Control, homologous BCG, homologous IV, heterologous IV-BCG, heterologous BCG-IV. Significant 67% and 66% total lesion score reductions were detected in homologous IV (IVx2) and heterologous IV-BCG groups when compared with Control group (F_4,16 = 6.393, p = 0.003; Bonferroni _{Control vs IVx2} p = 0.026, Tukey _{Control vs IV-BCG} p = 0.021). No significant differences were found for homologous BCG (although a 48% reduction in total lesion score was recorded) and BCG-IV (3% reduction). Heterologous regimes did not improve protection over homologous regimes in the wild boar model and showed variable results from no protection to similar protection as homologous regimes. Therefore, homologous regimes remain the best option to vaccinate wild boar against TB. Moreover, vaccine sequence dramatically influenced the outcome underlining the relevance of studying the effects of prior sensitization in the outcome of vaccination.     

Campylobacter infection in wild artiodactyl species from southern Spain: Occurrence,risk factors and antimicrobial susceptibility

A cross-sectional study was performed to assess the occurrence of Campylobacter species and to identify potential associated risk factors for wild artiodactyl species in southern Spain. Campylobacter species were isolated in 55 of 363 (15.2%) faecal samples. Campylobacter was identified in faeces from wild boar (49/126; 38.9%), red deer (5/179; 2.8%) and mouflon (1/13; 7.7%) but not from fallow deer (0/45). The isolated Campylobacter species were identified as C. jejuni (2 isolates; 3.6%), C. coli (11 isolates; 20.0%) and C. lanienae (37 isolates; 67.3%). Five isolates (9.1%) could not be identified at the species level. This report is the first to describe C. lanienae infection in wild ruminant species. Resistance to erythromycin (4.8%), ciprofloxacin (37.5%), tetracycline (52.9%) and streptomycin (55%) were detected. C. lanienae presented a significantly higher number of susceptible isolates to ciprofloxacin and tetracycline than C. coli. Due to the low number of positive wild ruminants, a Generalised Estimating Equations model was only carried out for wild boar. The model indicated that the risk factors associated with Campylobacter infection were the density of wild boar (>10/100 ha) (OR: 3.05; CI_95%: 2.2–4.3), the presence of artificial waterholes (OR: 3.67; CI_95%: 1.3–10.5) and the winter season (OR: 3.30; CI_95%: 1.9–5.8). Campylobacter infection is widespread in wild boar populations in southern Spain. These findings suggest that wild artiodactyls, particularly wild boar, constitute a reservoir of Campylobacter species, including resistant and multi-resistant strains, which may be of public health concern.     

Blood-feeding patterns of horse flies in the French Pyrenees

Horse flies can mechanically transmit Besnoitia besnoiti, the agent of bovine besnoitiosis. Although previously limited to enzootic areas, especially the French Pyrenees Mountains, bovine besnoitiosis is now considered a re-emerging disease in western Europe. To improve understanding of the role of horse flies as mechanical vectors, this study investigated their blood-feeding ecology in the eastern French Pyrenees, in two high-altitude summer pastures whose main domestic ungulates were cattle, and in a wildlife park with native fauna. Species-specific PCR assays were conducted to identify the sources of blood meals: wild boar, horse, cattle (or bison), sheep (or mouflon), goat, red deer, roe deer and izard (or Pyrenean chamois). In La Mouline pasture, tabanids (N = 20) fed on red deer (70%) and cattle (30%). In Mantet pasture, tabanids (N = 24) fed on cattle (52%), red deer (20%), wild boar (16%), horse (8%) and sheep (4%). In the wildlife park, Tabanus bromius (N = 32), the most abundant species collected, fed on red deer (85%), bison (9%) and wild boar (6%). Despite relatively high densities in both the pastures and in the wildlife park, small wild ungulates (izard, mouflon and roe deer) were not detected as a source of blood meals. Only two mixed blood meals were identified in two specimens of T. bromius: cattle/horse for the specimen collected in the pastures, and bison/wild boar for the specimen collected in the wildlife park. Our findings showed that tabanids display a level of opportunistic feeding behaviour, in addition to a preference for red deer, the latter being particularly true for Philipomyia aprica, the most abundant species collected in the pastures.     

Prevalence and risk factor investigation of Campylobacter species in beef cattle feces from seven large commercial feedlots in Alberta,Canada

This fecal prevalence study targeted cattle from 7 large (10 000 to > 40 000 head) commercial feedlots in Alberta as a means of establishing Campylobacter levels in cattle just prior to animals entering the food chain. Overall, 87% [95% confidence interval (CI) = 86–88] of 2776 fresh pen-floor fecal samples were culture positive for Campylobacter species, with prevalences ranging from 76% to 95% among the 7 feedlots. Campylobacter spp. prevalence was 88% (95% CI = 86–90) in the summer (n = 1376) and 86% (95% CI = 85–88) in the winter (n = 1400). In addition, 69% (95% CI = 66–71) of 1486 Campylobacter spp. positive samples were identified as Campylobacter jejuni using hippurate hydrolysis testing. Of those, 64% (95% CI = 58–70) of 277 and 70% (95% CI = 67–72) of 1209 Campylobacter isolates were identified as C. jejuni in winter and summer, respectively. After accounting for clustering within pen and feedlot, feedlot size and the number of days on feed were associated with Campylobacter spp. isolation rates. The high isolation rates of Campylobacter spp. and C. jejuni in feedlot cattle feces in this study suggest a potential role for feedlot cattle in the complex epidemiology of campylobacters in Alberta.     

Seroprevalence of Toxoplasma gondii in wild boar and deer in Brandenburg,Germany

Consumption of game in Germany has increased during the past 10 years. Wild boar (Sus scrofa), roe deer (Capreolus capreolus) and red deer (Cervus elaphus) are the most frequently hunted and consumed game animals in Germany, yet information on the occurrence of zoonotic pathogens in these animal species is scarce. To better estimate the public health risk emanating from handling and consumption of game, this study investigated seroprevalences of Toxoplasma gondii in game hunted in the German federal state of Brandenburg during two hunting seasons from 2017 to 2019. Toxoplasma gondii‐specific antibodies were detected in 24.4% (44/180, 95% CI: 18.4%–31.4%) of wild boar, 12.8% (16/125, 95% CI: 7.5%–20%) of roe deer and 6.4% (3/47, 95% CI: 1.3%–17.5%) of red deer using a commercial ELISA kit. Seroprevalences were similar in the two hunting seasons. Correlation between sex and seropositivity could not be observed. A rise in seroprevalence was seen with increasing age in all studied game species. Observed seroprevalences suggest that T. gondii is endemic in the sylvatic environment in the German federal state of Brandenburg and imply that game could represent a relevant source for human T. gondii infection.     

Evaluation of baits for oral vaccination of European wild boar piglets

The objective of this study was to develop and evaluate new baits for the oral delivery of vaccine preparations to 2–4 month-old wild boar piglets. Baits were prepared using a matrix composed of wild boar feed, wheat flour, paraffin, sacarose and cinnamon-truffle powder attractant with polyethylene capsules dipped into the matrix to introduce vaccine formulation. Physical stability studies demonstrated that baits were stable for at least three days at temperatures as high as 42 °C. Recombinant Escherichia coli expressing the membrane-displayed BM95-MSP1a fusion protein were used to test bacterial viability in the baits and the antibody response in orally immunized wild boar. The E. coli viability was not significantly affected after bait incubation at 25 and 37 °C for 96 h. Bait acceptance studies using artificial feeders in the field showed that baits were accepted by 2–3 month-old animals, the preferred age for vaccination. Orally immunized wild boar piglets excreted recombinant E. coli in the feces and developed antibody titers to recombinant BM95-MSP1a protein, thus confirming that vaccine composition was released and reached the wild boar gastrointestinal track. The results of these experiments support the use of these baits for oral delivery of vaccine formulations to 2–4 month-old wild boar piglets.     

Acceptance and palatability for domestic and wildlife hosts of baits designed to deliver a tuberculosis vaccine to wild boar piglets

Tuberculosis (TB) caused by Mycobacterium bovis, a member of the Mycobacterium tuberculosis complex, is an important health problem worldwide. The control of TB through vaccination of wildlife reservoirs may potentially have advantages over other management strategies. The most practical approach to deliver vaccines to wildlife is using oral baits that are stable under field conditions and effective in reaching the target species. Baits were developed in our laboratory to deliver oral vaccines to wild boar piglets. However, these baits were well accepted by other wild species. Therefore, bait consumption by different M. bovis hosts was evaluated herein. The results showed that the baits were well accepted by cattle, feral pigs, and adult red deer whereas small mammals like badgers and possums showed varying bait acceptance. Bait acceptance by different species has the advantage of targeting more than one wildlife reservoir when they coexist in the same area and need to be vaccinated for TB control. However, bait delivery methods such as the use of selective feeders to target the desired species should be developed to avoid bait consumption by other species.     

Molecular identification of tick-borne bacteria in wild animals and their ticks in Central Anatolia,Turkey

Wild animals fulfill an important mission in the ecology of tick-borne diseases as both suitable hosts to tick vectors and reservoirs of the pathogens. However, current data regarding the role of wild animals in the ecology of tick-borne pathogens is insufficient and more investigations are required. In this study, we investigated tick-borne bacterial pathogens in wild boar, hare, and fox and their ticks in Turkey. A total of 102 tick pools comprised of 445 ticks and blood samples were analyzed for the presence of bacterial DNA by PCRs targeted rickettsial gltA and ompA genes, 5S-23S rDNA gene for Borrelia spp., and msp4 gene for Anaplasma spp. As a result of PCR and sequence analyses, three pathogenic spotted fever group (SFG) rickettsiae, two SFG rickettsiae with unknown pathogenicity and one pathogenic Borrelia burgdorferi sensu lato were detected in samples obtained from wild animals. Rickettsia slovaca was detected in ticks (13.7% of tick pools) collected from wild boars and blood of a wild boar. In addition, the presences of R. hoogstraalii (19.6% of tick pools), R. aeschlimannii (5.8% of tick pools), R. sibirica subsp. mongolitimonae (1.9% of tick pools) and Candidatus R. goldwasserii (0.9% of tick pools) were detected in ticks collected from wild animals. Furthermore, B. burgdorferi sensu stricto was detected in a tick pool collected from a wild boar. This is the first report on the presence of Candidatus R. goldwasserii in Turkey. Consequently, this study shows that pathogenic Rickettsia and Borrelia species are circulating in Turkish wildlife and these pathogens can pose a threat to human health. Also, it has been determined that the investigated wild animals play a role as maintenance host for vector ticks; therefore, these animals must also be considered in the ecology of the mentioned pathogens.     

Progress in the control of bovine tuberculosis in Spanish wildlife

Despite the compulsory test and slaughter campaigns in cattle, bovine tuberculosis (bTB) is still present in Spain, and the role of wildlife reservoirs is increasingly recognized. We provide an update on recent progress made in bTB control in Spanish wildlife, including aspects of epidemiology, surveillance, host-pathogen interaction and wildlife vaccination. At the high densities and in the particular circumstances of Mediterranean environments, wild ungulates, mainly Eurasian wild boar and red deer, are able to maintain Mycobacterium bovis circulation even in absence of domestic livestock. Infection is widespread among wild ungulates in the south of the country, local infection prevalence being as high as 52% in wild boar and 27% in red deer. Risk factors identified include host genetic susceptibility, abundance, spatial aggregation at feeders and waterholes, scavenging, and social behaviour. An increasing trend of bTB compatible lesions was reported among wild boar and red deer inspected between 1992 and 2004 in Southwestern Spain. Sporadic cases of badger TB have been detected, further complicating the picture. Gene expression profiles were characterized in European wild boar and Iberian red deer naturally infected with M. bovis. The comparative analysis of gene expression profiles in wildlife hosts in response to infection advanced our understanding of the molecular mechanisms of infection and pathogenesis, revealed common and distinctive host responses to infection and identified candidate genes associated with resistance to bTB and for the characterization of host response to infection and vaccination. Ongoing research is producing valuable knowledge on vaccine delivery, safety and efficacy issues. Baits for the oral delivery of BCG vaccine preparations to wild boar piglets were developed and evaluated. The use of selective feeders during the summer was found to be a potentially reliable bait-deployment strategy. Safety experiments yielded no isolation of M. bovis BCG from faeces, internal organs at necropsy and the environment, even after oral delivery of very high doses. Finally, preliminary vaccination and challenge experiments suggested that a single oral BCG vaccination may protect wild boar from infection by a virulent M. bovis field strain.     

Evaluation of single and comparative intradermal tuberculin tests for tuberculosis eradication in caprine flocks in Castilla y León (Spain)

Goats can act as reservoirs for tuberculosis (TB) infection. The main etiological agents of TB in goats are Mycobacterium caprae and Mycobacterium bovis and they infect also a wide range of domestic and wild animals and humans. Control programmes based mainly on the application of single and comparative intradermal tuberculin (SIT and SCIT respectively) tests are being implemented in certain regions of Spain with a high density of caprine flocks as Castilla y León, including goats with epidemiological relationship with cattle. The aim of this study was to evaluate the performance of the intradermal tests in naturally TB-infected caprine flocks from this region. The study was performed using data from 17,450 goats in 54 different flocks that were classified as TB-infected in the control programmes executed in 2010 and 2011. Data from 1237 goats from 7 dairy flocks depopulated after the first intradermal testing were used to estimate the sensitivity (Se) using bacteriology as the gold-standard. Overall Se of the SIT test using the severe interpretation was 43.9% (CI 95%, 40.4–47.4) and decreased to 38.8% (CI 95%, 35.5–42.3) using the standard interpretation. Overall Se of the SCIT test ranged between 21.3% (CI 95%, 17.6–25.4) and 7% (CI 95%, 4.9–9.8) depending of the interpretation criteria. A significant weak positive correlation was found between age and skin fold thickness (Spearman’s test p < 0.05). Results from this study yielded, in general, low Se values probably due the systematic detection and slaughter of reactors as a consequence of the eradication programme in previous years or the presence of factors that may interfere in the diagnosis. Therefore, these results suggest the necessity of including ancillary diagnostic tools and/or strict interpretation criteria to maximize detection of positive animals in infected settings.     

Molecular detection of Leptospira spp. in wild boar (Sus scrofa) hunted in Liguria region (Italy)

Leptospirosis is a re-emerging and widespread zoonosis, worldwide distributed, due to a wide variety of wild and domestic animal species able to act as natural or accidental hosts. During last years, in Europe, as in Italy, wild boar (Sus scrofa) population is increased. This animal represents a reservoir for different etiological agents, such as Leptospira. The aim of this investigation was to evaluate the prevalence of Leptospira spp. in wild boar hunted in Liguria region (Italy) during two-year hunting seasons. From 611 hunted wild boar, kidneys were collected. DNA was extracted from each organ and different targets were used to detect pathogenic (lipL32 gene), intermediate (16S rRNA gene) and saprophytic (23S rRNA gene) Leptospira by Taqman-based RealTime-PCR assays. Overall, kidneys were sampled from 282 adults, 155 sub-adults and 174 young wild boar (in total 314 males and 298 females). By RealTime PCR 77 kidneys were positive and, among these, 74 resulted positive for pathogenic (96.10%) and 3 (3.90%) for intermediate Leptospira. No significant differences in pathogenic Leptospira infection ratio were detected between male (11.50%) and female (12.75%). Only 13 sub-adult animals (8.39%) resulted infected by pathogenic Leptospira; 23 young animals (13.22%) and 38 adult animals (13.47%) were positive. The results of this study confirmed the importance of wild boar in the epidemiology of leptospirosis, which is able to infect other animal species (domestic and wild) including humans. Rarely, intermediate Leptospira could be able to infect wild boar with a renal localization that can contribute to their shedding and circulation.     

Fasciola hepatica in wild boar (Sus scrofa) from Italy

Fasciola hepatica is a trematode infecting ruminants worldwide, occasionally reported in a wide range of animal species, including humans. According to the WHO, fasciolosis is recognized as a re-emerging neglected tropical disease, responsible for endemic and epidemic outbreaks in humans. Although the main hosts of the parasite are represented by cattle, sheep and goats, wildlife may be involved in its circulation. Here we firstly report F. hepatica in a wild boar from Italy (southern area) and characterize it both morphologically and molecularly. The nad1 gene analysis of specimens analyzed, revealed a high genetic similarity with those of humans from Iran and Peru, as well as a close phylogenetic relationship to those in ruminants from Brazil, Ecuador and Egypt. Considering the increase in the wild boar populations in urban and peri-urban areas, a potential role of this ungulate in the circulation of this zoonotic trematode is suggested.     

Hepatitis E Virus Antibody Prevalence in Wildlife in Poland

Hepatitis E is an important public health problem mostly in developing but occasionally also in industrialized countries. Domestic and wildlife animals are considered reservoirs of the hepatitis E virus (HEV). Since no information on the prevalence of autochthonous HEV infections in human and animal in Poland is available, the aim of the study was to investigate the HEV seroprevalence of different wildlife species as potential virus reservoirs in the country. No HEV antibodies were found in any of the sera collected from the red deer (Cervus elaphus), European bison (Bison bonasus), roe deer (Capreolus capreolus), elk (Alces alces), fallow deer (Dama dama), sika deer (Cervus nippon), Tatra chamois (Rupicapra rupicapra tatrica) or brown bear (Ursus arctos). HEV‐specific antibodies were detected in 44.4% (95% CI 38.3–50.7) serum samples originated only from wild boars. The percentage of seropositive wild boars differed significantly between the provinces and was positively correlated with the wild boar density and rurality of the area. This study showed that HEV circulates among wild boar population in Poland, and this species should be considered as an important reservoir of the virus.