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BACKGROUND: Tuberculosis (TB) due to Mycobacterium caprae is endemic in goat herds and free-ranging wild boars in Spain, causing infections in other livestock or wild animals to a lesser extent. TB infection in foxes is infrequently reported and they are usually considered spillover hosts of TB. CASE PRESENTATION: A blind, depressed and severely emaciated red fox (Vulpes vulpes) was admitted to a rehabilitation center. After clinical examination it was humanely sacrificed. At necropsy, generalized TB lesions were observed that were subsequently confirmed by histopathology along with a co-infection with canine distemper virus. M. caprae was isolated from mycobacterial culture and spoligotype SB0415 was identified. Whole genome sequencing (WGS) of the isolated M. caprae was carried out and single nucleotide polymorphisms (SNP) were compared with other sequences of M. caprae isolated from livestock and wildlife of the same area throughout the last decade. CONCLUSIONS: This is the first reported case of TB due to M. caprae in a fox in the Iberian Peninsula. WGS and SNP analysis, together with spatial-temporal investigations, associated this case with recent M. caprae outbreaks in cattle and goat herds of the area. The results indicated transmission of M. caprae between livestock and the fox, suggesting that this species may occasionally play a role in the epidemiology of animal TB.
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Doenças dos Bovinos , Doenças das Cabras , Mycobacterium bovis , Doenças dos Suínos , Tuberculose , Animais , Animais Selvagens , Bovinos , Raposas , Cabras/microbiologia , Granuloma/veterinária , Gado , Mycobacterium bovis/genética , Sus scrofa/microbiologia , Suínos , Tuberculose/epidemiologia , Tuberculose/microbiologia , Tuberculose/veterináriaRESUMO
Mycobacterium microti is a member of the Mycobacterium tuberculosis complex that causes pathology in many mammals. M. microti infections have been found in some countries in Europe. We report an outbreak of tuberculosis caused by M. microti in wild boars in Spain.
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Mycobacterium tuberculosis , Sus scrofa/microbiologia , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/microbiologia , Tuberculose/veterinária , Animais , Surtos de Doenças , Geografia Médica , História do Século XXI , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/genética , Vigilância em Saúde Pública , Espanha/epidemiologia , Suínos , Doenças dos Suínos/históriaRESUMO
BACKGROUND: Control of animal tuberculosis (TB) through vaccination has emerged as a long-term strategy to complement test and slaughter control strategy. A pilot trial under field conditions was conducted in a goat herd with high TB prevalence to assess the efficacy of the Mycobacterium bovis BCG vaccine. RESULTS: Twenty-three goat kids vaccinated with BCG and other 22 unvaccinated control kids were euthanized at 18 months post-vaccination. Gross pathological and histopathological examination of target tissues was performed for detection of tuberculous lesions and assessment of vaccine efficacy. Mycobacterial culture and DNA detection were used to confirm Mycobacterium caprae infection. Vaccination significantly reduced the number of animals with TB lesions compared to unvaccinated controls (35% and 77%, respectively; P < 0.01). This reduction was even higher if only extra-pulmonary infection was considered (17% and 68%, respectively; P < 0.001). CONCLUSIONS: This trial demonstrates that BCG vaccination of goats can significantly reduce the TB lesion rates in high disease exposure conditions, indicating that vaccination could contribute to the control of TB in domestic goats.
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Vacina BCG/uso terapêutico , Doenças das Cabras/prevenção & controle , Mycobacterium/imunologia , Tuberculose/veterinária , Animais , Vacina BCG/imunologia , Feminino , Doenças das Cabras/imunologia , Doenças das Cabras/microbiologia , Cabras/imunologia , Cabras/microbiologia , Masculino , Resultado do Tratamento , Tuberculose/imunologia , Tuberculose/microbiologia , Tuberculose/prevenção & controleRESUMO
Mycobacterium caprae is linked to regular outbreaks of tuberculosis (TB) in geographically distinct caprine populations across Europe, namely Iberia where this ecovar may represent 8% of total animal TB cases, circulating in multi-host communities encompassing domestic ruminants and wildlife, representing severe financial losses. It also causes zoonotic human disease. In this work, we undertake the first phylodynamic and phylogeographic analyses of M. caprae to reconstruct past demography and transmission chains. First, we examined the worldwide diversity of M. caprae based on 229 unpublished and publicly available whole genome sequences, depicting Asian, Central-East European, and Iberian clades. Phylodynamic analyses of the SB0157 Iberian clade (n=81) positioned the most recent common ancestor in goats, around 100 years ago. Host transition events were common between goats, wild boars, and humans, possibly resulting from mixed farming, extensive management, and close human proximity, facilitating interspecific transmission. We show the spread of M. caprae on multiple scales due to local and transnational animal trade, supporting historical and sustained cross-species transmission in Iberia. We highlight the value of intersecting genomic epidemiology with molecular ecology to resolve epidemiological links and show that an EU-official eradication program in goats is utterly needed to control TB in a multi-host scenario.
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Mycobacterium microti is a member of the Mycobacterium tuberculosis complex that seldom causes disease in livestock and humans. This study evaluated the effects on immunodiagnosis and the pathological findings in goats after experimental exposure by different routes and doses to M. microti. In a first experiment goats were challenged orally (PO, n = 7) or intranasally (IN, n = 7) with 104 CFU. In a second experiment, the endobronchial route was assessed, with a low dose of 102 CFU (EB-LD, n = 7) and a high dose of 105 CFU (EB-HD, n = 7) as well as the subcutaneous route (SC, n = 5). Temperature, body weight, clinical signs and immunological responses were monitored. Pathological evaluation was carried out and samples were processed for mycobacterial detection. RESULTS: demonstrated the induction of a subclinical pulmonary infection in all the EB-HD challenged animals. Infection was also confirmed in one animal of the SC group, but not in the EB-LD, PO or IN groups. Two animals belonging to the EB-HD and SC groups, respectively, showed positive results to the single intradermal tuberculin test, and another two animals of the EB-HD and EB-LD groups showed doubtful (inconclusive) results, indicating that M. microti can induce mild responses to tuberculin skin testing. No positive results were observed when defined antigens absent in M. microti (ESAT-6 and CPF-10) were used. Our results indicate that animals exposed to M. microti can yield positive results to the skin tests currently performed in livestock tuberculosis eradication campaigns and reinforce the need to use specific antigens in antemortem tests to avoid interference with M. bovis/M. caprae diagnosis.
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Mycobacterium bovis , Mycobacterium tuberculosis , Tuberculose Pulmonar , Humanos , Animais , Teste Tuberculínico/veterinária , Tuberculina , Cabras , Tuberculose Pulmonar/veterináriaRESUMO
Adiaspiromycosis is a nontransmissible infectious pulmonary disease caused by the inhalation of propagules from fungal species belonging to the family Ajellomicetaceae, especially Emergomyces crescens. Adiaspiromycosis caused by E. crescens has been recorded in a broad number of species worldwide, with small burrowing mammals being considered the main hosts for this environmental pathogen. Only a handful of studies on adiaspiromycosis in European wildlife has been published to date. We assessed the occurrence of adiaspiromycosis in wild rodents (Murinae and Arvicolinae) from the central Spanish Pyrenees (NE Spain). The lungs of 302 mice and 46 voles were screened for the presence of adiaspores through histopathologic examination. Pulmonary adiaspiromycosis was recorded in 21.6% of all individuals (75/348), corresponding to 63/299 wood mice (Apodemus sylvaticus) and 12/40 bank voles (Myodes glareolus). Adiaspore burden varied highly between animals, with a mean of 0.19 spores/mm2 and a percentage of affected lung tissue ranging from <0.01% to >8%. These results show that the infection is present in wild rodents from the central Spanish Pyrenees. Although the impact of this infection on nonendangered species is potentially mild, it might contribute to genetic diversity loss in endangered species.
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Pneumopatias Fúngicas , Doenças dos Roedores , Animais , Espanha/epidemiologia , Pneumopatias Fúngicas/veterinária , Mamíferos , Murinae , Arvicolinae , Doenças dos Roedores/epidemiologiaRESUMO
Background: Goats are natural hosts of tuberculosis (TB) and are a valid animal model to test new vaccines and treatments to control this disease. In this study, a new experimental model of TB in goats based on the intranasal nebulization of Mycobacterium caprae was assessed in comparison with the endobronchial route of infection. Methods: Fourteen animals were divided into two groups of seven and challenged through the endobronchial (EB) and intranasal (IN) routes, respectively. Clinical signs, rectal temperature, body weight, and immunological responses from blood samples were followed up throughout the experiment. All goats were euthanized at 9 weeks post-challenge. Gross pathological examination, analysis of lung lesions using computed tomography, and bacterial load quantification in pulmonary lymph nodes (LNs) by qPCR were carried out. Results: The IN-challenged group showed a slower progression of the infection: delayed clinical signs (body weight gain reduction, peak of temperature, and apparition of other TB signs) and delayed immunological responses (IFN-γ peak response and seroconversion). At the end of the experiment, the IN group also showed significantly lower severity and dissemination of lung lesions, lower mycobacterial DNA load and volume of lesions in pulmonary LN, and higher involvement of the nasopharyngeal cavity and volume of the lesions in the retropharyngeal LN. Conclusion: The results indicated that the IN challenge with M. caprae induced pathological features of natural TB in the lungs, respiratory LN, and extrapulmonary organs but extremely exaggerating the nasopharyngeal TB pathological features. On the other hand, the EB route oversized and accelerated the pulmonary TB lesion progression. Our results highlight the need to refine the inoculation routes in the interest of faithfully reproducing the natural TB infection when evaluating new vaccines or treatments against the disease.
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The single and comparative intradermal tuberculin tests (SITT and CITT) are official in vivo tests for bovine tuberculosis (TB) diagnosis using bovine and avian purified protein derivatives (PPD-B and PPD-A). Infection with bacteria other than Mycobacterium tuberculosis complex (MTC) can result in nonspecific reactions to these tests. We evaluated the performance of the skin test with PPDs and new defined antigens in the guinea pig model. A standard dose (SD) of Rhodococcus equi, Nocardia sp., M. nonchromogenicum, M. monacense, M. intracellulare, M. avium subsp. paratuberculosis, M. avium subsp. avium, M. avium subsp. hominissuis, M. scrofulaceum, M. persicum, M. microti, M. caprae and M. bovis, and a higher dose (HD) of M. nonchromogenicum, M. monacense, M. intracellulare, M. avium subsp. paratuberculosis were tested using PPD-B, PPD-A, P22, ESAT-6-CFP-10-Rv3615c peptide cocktail long (PCL) and fusion protein (FP). The SD of R. equi, Nocardia sp., M. nonchromogenicum, M. monacense, M. intracellulare and M. avium subsp. paratuberculosis did not cause any reactions. The HD of M. nonchromogenicum, M. monacense, M. intracellulare, and M. avium subsp. paratuberculosis and the SD of M. avium subsp. hominissuis, M. scrofulaceum and M. persicum, caused nonspecific reactions (SIT). A CITT interpretation would have considered M. avium complex and M. scrofulaceum groups negative, but not all individuals from M. nonchromogenicum HD, M. monacense HD and M. persicum SD groups. Only animals exposed to M. bovis and M. caprae reacted to PCL and FP. These results support the advantage of complementing or replacing PPD-B to improve specificity without losing sensitivity.
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Mycobacterium , Paratuberculose , Tuberculose Bovina , Animais , Cobaias , Bovinos , Tuberculina , Tuberculose Bovina/diagnóstico , Antígenos , Teste TuberculínicoRESUMO
BACKGROUND: Most countries carrying out campaigns of bovine tuberculosis (TB) eradication impose a ban on the use of mycobacterial vaccines in cattle. However, vaccination against paratuberculosis (PTB) in goats is often allowed even when its effect on TB diagnosis has not been fully evaluated. To address this issue, goat kids previously vaccinated against PTB were experimentally infected with TB. RESULTS: Evaluation of interferon-γ (IFN-γ) secretion induced by avian and bovine tuberculins (PPD) showed a predominant avian PPD-biased response in the vaccinated group from week 4 post-vaccination onward. Although 60% of the animals were bovine reactors at week 14, avian PPD-biased responses returned at week 16. After challenge with M. caprae, the IFN-γ responses radically changed to show predominant bovine PPD-biased responses from week 18 onward. In addition, cross-reactions with bovine PPD that had been observed in the vaccinated group at week 14 were reduced when using the M. tuberculosis complex-specific antigens ESAT-6/CFP-10 and Rv3615c as new DIVA (differentiation of infected and vaccinated animals) reagents, which further maintained sensitivity post-challenge. Ninety percent of the animals reacted positively to the tuberculin cervical comparative intradermal test performed at 12 weeks post-infection. Furthermore, post-mortem analysis showed reductions in tuberculous lesions and bacterial burden in some vaccinated animals, particularly expressed in terms of the degree of extrapulmonary dissemination of TB infection. CONCLUSIONS: Our results suggest a degree of interference of PTB vaccination with current TB diagnostics that can be fully mitigated when using new DIVA reagents. A partial protective effect associated with vaccination was also observed in some vaccinated animals.
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Doenças das Cabras/prevenção & controle , Paratuberculose/prevenção & controle , Tuberculose/veterinária , Animais , Proteínas de Bactérias , Bovinos , Doenças dos Bovinos/prevenção & controle , Proteção Cruzada , Doenças das Cabras/sangue , Cabras , Interferon gama/sangue , Paratuberculose/diagnóstico , Especificidade da Espécie , Tuberculina/imunologia , Tuberculose/diagnóstico , Tuberculose/prevenção & controleRESUMO
Voles are maintenance hosts of Mycobacterium microti. In line with the goal to eradicate tuberculosis (TB) in livestock, the role of this mycobacteria needs to be assessed since it might interfere with current M. bovis/M. caprae surveillance strategies. To better understand the pathogenesis of TB in voles, an experimental infection model was set up to reproduce M. microti infection in laboratory Bank voles (Myodes glareolus). Two infection routes (intragastric and intraperitoneal) and doses (105 and 106 CFU/0.1 mL) were assessed. Voles were culled at different post-infection time points. Serology, histopathology, acid-fast bacilli staining, qPCR, and mycobacterial culture from tissues were performed. In addition, qPCR from feces and oral swabs were conducted to assess bacterial shedding. The model allowed us to faithfully reproduce the disease phenotype described in free-ranging voles and characterize the pathogenesis of the infection. Most animals showed multifocal and diffuse granulomatous lesions in the liver and spleen, respectively. Less frequently, granulomas were observed in lungs, lymph nodes, muscles, and salivary gland. Mycobacterial DNA was detected in feces from a few animals but not in oral swabs. However, one contact uninfected vole seroconverted and showed incipient TB compatible lesions, suggesting horizontal transmission between voles.
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Caprine tuberculosis (TB) is a zoonosis caused by members of the Mycobacterium tuberculosis complex (MTBC). Caprine TB eradication programmes are based mainly on intradermal tuberculin tests and slaughterhouse surveillance. Different factors may affect the performance of the TB diagnostic tests used in caprine herds and, therefore, their ability to detect infected animals. The present study evaluates the effect of the fraudulent administration of two anti-inflammatory substances, dexamethasone and ketoprofen, on the performance of the TB diagnostic techniques used in goats, as well as the suitability of high performance liquid chromatography (HPLC) for their detection in hair samples. The animals (n = 90) were distributed in three groups: (1) a group treated with dexamethasone (n = 30); a second group treated with ketoprofen (n = 30); and a third non-treated control group (n = 30). Both dexamethasone and ketoprofen groups were subjected to intramuscular inoculation with the substances 48 h after the administration of bovine and avian purified protein derivatives (PPDs), that is, 24 h before the tests were interpreted. All the animals were subjected to the single and comparative intradermal tuberculin (SIT and CIT, respectively) tests, interferon-gamma release assay (IGRA) and P22 ELISA. The number of SIT test reactors was significantly lower in the dexamethasone (p = 0.001) and ketoprofen (p < 0.001) groups 72 h after the bovine PPD inoculation compared with the control group. A significantly higher number of positive reactors to IGRA was detected within the dexamethasone group (p = 0.016) 72 h after PPD administration compared to the control group. Dexamethasone and ketoprofen detection in either hair or serum samples was challenging when using HPLC since these substances were not detected in animals whose skin fold thickness (SFT) was reduced, what could be an issue if they are used for fraudulent purposes. In conclusion, the parenteral administration of dexamethasone or ketoprofen 48 h after the PPDs administration can significantly reduce the increase in SFT (mm) and subsequently the number of positive reactors to SIT test.
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This study aimed to assess the efficacy of a heat-inactivated Mycobacterium caprae (HIMC) vaccine in goats experimentally challenged with the same strain of M. caprae. Twenty-one goats were divided into three groups of seven: vaccinated with heat-inactivated Mycobacterium bovis (HIMB), with HIMC and unvaccinated. At 7 weeks post-vaccination all animals were endobronchially challenged with M. caprae. Blood samples were collected for immunological assays and clinical signs were recorded throughout the experiment. All goats were euthanized at 9 weeks post-challenge. Gross pathological examination, analysis of lung pathology using computed tomography, and bacterial load quantification in pulmonary lymph nodes (LN) by qPCR were carried out. Only HIMC vaccinated goats showed a significant reduction of lung lesions volume and mycobacterial DNA load in LN compared to unvaccinated controls. Both vaccinated groups showed also a significant reduction of the other pathological parameters, an improved clinical outcome and a higher proportion of IFN-γ-producing central memory T cells after vaccination. The results indicated that homologous vaccination of goats with HIMC induced enhanced protection against M. caprae challenge by reducing lung pathology and bacterial load compared to the heterologous vaccine (HIMB). Further large-scale trials are necessary to assess the efficacy of autovaccines under field conditions.
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Autovacinas , Mycobacterium bovis , Tuberculose , Animais , Tuberculose/microbiologia , Cabras/microbiologia , Temperatura AltaRESUMO
Bovine tuberculosis (bTB) is a zoonotic disease caused mainly by Mycobacterium bovis, which is associated with major economic losses for milk and meat producers. The objective of this trial was to assess the efficacy of the BCG Russia strain in a cohort study performed under field conditions, with the vaccination of calves in seven dairy farms from a high prevalence area in central Chile. The trial was performed with 501 animals, subcutaneously vaccinated with 2-8 × 105 colony-forming units of BCG, whilst 441 matched control animals received a saline placebo. Peripheral blood was collected at 6, 12 and 18 months post-vaccination, and infection status was determined using the IFNγ release assay in conjunction with the DIVA (Detecting Infected amongst Vaccinated Animals) antigens ESAT-6, CFP-10 and Rv3615c. The BCG vaccine showed a low but significant level of protection of 22.4% (95% CI 4.0 to 36.4) at the end of the trial. However, diverse levels of protection and a variable duration of immunity were observed between trial herds. This diverse outcome could be influenced by the general health condition of calves and their exposition to non-tuberculous mycobacteria. These results suggest that BCG vaccination of dairy calves in a natural transmission setting confers variable protection to animals against bTB in a high prevalence area.
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Tuberculosis (TB) in wildlife challenges epidemiological surveillance and disease control. An outbreak of TB was detected in a free-ranging wild boar population of a Natural Park in Catalonia (Spain) and the outbreak investigation was conducted in the area. During the study period (2015-2020), 278 wild boars were analysed by gross pathology, histopathology, mycobacterial culture and DVR-spoligotyping. In addition, all cattle (49) and goat (47) herds of the area were tested with tuberculin skin test. TB compatible lesions were detected in 21 wild boars, and Mycobacterium caprae was isolated in 17 of them with two different spoligotypes: SB0415 (13) and SB1908 (4). Only two goat herds showed TB positive animals that were subsequently slaughtered. M. caprae with the spoligotypes SB0416 and SB0415 were isolated from these animals. To investigate the phylogenetic relationships and the transmission chain of the outbreak, nine strains isolated from six wild boars and three goats of the study area were analysed by whole genome sequencing (WGS) followed by single nucleotide polymorphism (SNP) analysis by maximum likelihood and median-joining network inference methods. Results indicated that infected wild boars maintained M. caprae strains circulation in their own population and have likely transmitted the infection to goats, thus acting as TB reservoirs, compromising the success of livestock TB eradication campaigns and posing a risk for public health. The results also highlighted the usefulness of WGS followed by SNP analysis in providing relevant epidemiological information when detailed contact data are missing.
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Doenças dos Bovinos/transmissão , Doenças das Cabras/transmissão , Mycobacterium tuberculosis/isolamento & purificação , Doenças dos Suínos/transmissão , Tuberculose/veterinária , Animais , Animais Selvagens , Bovinos , Cabras , Mycobacterium tuberculosis/classificação , Filogenia , Prevalência , Espanha , Sus scrofa , Suínos , Tuberculose/transmissão , Sequenciamento Completo do Genoma/veterináriaRESUMO
Vaccination has been proposed as a supplementary tool for the control of tuberculosis in livestock. The long-term immunogenicity elicited by bacillus Calmette-Guerin (BCG) and the efficacy of revaccination were investigated in thirty goat kids distributed into three groups: unvaccinated controls, BCG (vaccinated at week 0) and BCG-BCG (vaccinated at weeks 0 and 56). Sixty-four weeks after the first vaccination, all animals were challenged with Mycobacterium caprae and examined post-mortem (pathology and bacterial load) at week 73. Antigen-specific interferon-gamma (IFN-γ) release was measured throughout the experiment. At week 59, peripheral blood mononuclear cells were stained for CD4, CD45RO and IFN-γ to determine the presence of antigen-specific cells secreting IFN-γ. The BCG-BCG group showed reductions in rectal temperatures, M. caprae DNA load in pulmonary lymph nodes (LN), the volume of lesions in pulmonary LN, mineralization in lungs, and higher weight gains compared to unvaccinated controls. IFN-γ responses were undetectable from 32 weeks after primary vaccination until revaccination, when the BCG-BCG group showed detectable IFN-γ production and a greater percentage of antigen-specific CD4+CD45RO+IFNγ+ and CD4-CD45RO+IFNγ+ cells compared to the BCG and control groups, which may be an indicator of the mechanisms of protection. Thus, re-vaccination of goats with BCG appears to prolong protection against infection with M. caprae.
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Vaccination of goats against tuberculosis (TB) has been promoted as an ancillary tool for controlling the disease in infected livestock herds. A three-year trial to assess the efficacy of BCG vaccine was carried out in five goat herds. At the beginning of the trial (month 0), all animals were tested for TB using thee different diagnostic tests. Animals negative to all tests were vaccinated with BCG and all replacement goat kids were also systematically vaccinated throughout the trial. All animals were tested by Interferon-gamma release assay (IGRA) using vaccine compatible reagents at months 6, 12, 24, and 36. The risk factors for TB infection were also evaluated. At the end of the study, four out of five farms showed variable reductions of the initial prevalence (93.5%, 28.5%, 23.2%, and 14.3% respectively), and an overall incidence reduction of 50% was observed in BCG vaccinated goats, although adult vaccinated goats showed higher incidences than vaccinated goat kids. The unvaccinated positive animals remaining in herds and adult BCG vaccinated goats significantly enhanced the risk of infection in vaccinated animals. A systematic vaccination of goats with BCG, together with the removal of positive unvaccinated animals, may contribute to reducing the TB prevalence in goat herds.
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Vacina BCG/administração & dosagem , Doenças das Cabras/epidemiologia , Cabras/microbiologia , Mycobacterium bovis/imunologia , Tuberculose/epidemiologia , Tuberculose/veterinária , Criação de Animais Domésticos/organização & administração , Animais , Fazendas/organização & administração , Doenças das Cabras/imunologia , Doenças das Cabras/prevenção & controle , Humanos , Imunogenicidade da Vacina , Interferon gama/biossíntese , Mycobacterium/imunologia , Mycobacterium/patogenicidade , Mycobacterium bovis/química , Mycobacterium bovis/patogenicidade , Prevalência , Espanha/epidemiologia , Tuberculose/imunologia , Tuberculose/prevenção & controle , Vacinação/métodos , Potência de VacinaRESUMO
Current eradication strategies of tuberculosis (TB) in goats mainly rely on the single intradermal tuberculin test (SIT) and single intradermal cervical comparative tuberculin tests (SICCTs). TB vaccination has been proposed as a cost-effective option in high-prevalence herds or countries where economic compensation for the slaughter of positive animals is not affordable. However, TB vaccination compromises the efficiency of tuberculin-based diagnostic tests. In this study, the performance of a new diagnostic platform, based on the P22 antigenic complex, was assessed for skin test (ST), interferon-gamma release assay (IGRA), and serology under different TB scenarios. The sensitivity (Se) of diagnostic tests was assessed in TB-infected goats from the same farm (herd A, N = 77). The specificity (Sp) was assessed in two TB-negative farms (both vaccinated against paratuberculosis): one TB unvaccinated (herd B, N = 77) and another vaccinated with bacille Calmette-Guérin (BCG) (herd C, N = 68). The single (s) P22-IGRA showed the highest Se among IGRA tests (91%), and the comparative (c) P22-ST showed the highest Sp (100% in herd B and 98% in herd C). Combined interpretation of techniques enabled the best diagnostic performances. Combining the SICCT + sP22-IGRA improved Se (97%) compared to SICCT + tuberculin-based IGRA (95%), with a reduction of Sp (95 and 100%, respectively). Besides, combination of P22-ELISA with cP22-ST or SICCT elicited a similar performance in the non-vaccination context (Se: 94 and 95%; Sp: 95 and 95%, respectively), but Sp was significantly higher for the combination with cP22-ST compared to SICCT in the TB vaccination context (95 and 79%, respectively). The combination of serological tests based on P22 and MPB83 showed higher complementarity and improved 13 percentage points the Se of P22-ELISA alone. These findings suggest that either cell-mediated or antibody-based diagnostic techniques, using the P22 antigen complex, can contribute to improve the immunodiagnostics of TB in goats under different TB control strategies.
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In Spain, the eradication of tuberculosis (TB) in cattle has had some setbacks and therefore we need to re-evaluate the current surveillance strategies. The Spanish cattle TB surveillance system consists of three components: a) routine skin testing, b) slaughterhouse surveillance, and c) pre-movement controls. Our objectives were to assess the effectiveness of the whole surveillance system and evaluate the relative contribution of each of those components, both at national and at the province level. The effectiveness was estimated based on both the sensitivity of detection per year and the time until detection. Moreover, we evaluated the impact of different factors on that effectiveness. We used a stochastic model that simulated the spread of Mycobacterium tuberculosis-complex (MTC) infection within cattle herds that was modified to incorporate the three components of TB surveillance. Input data, at the province level, on cattle movements off-farm or the frequency of the routine screening were provided by the Spanish Ministry for Agriculture, Fisheries and Food. Under the current conditions, 96.1% of Spanish herds were detected within one year after their infection (i.e. mean sensitivity of TB surveillance), although that detection took on average 178 days. The surveillance system effectiveness was highly dependent on the routine skin testing, responsible for the detection of almost 90% of the infected herds, while slaughterhouse surveillance and pre-movement controls contributed only to the identification of a small proportion of infected herds. We observed substantial differences in the effectiveness of the surveillance components among Spanish provinces, although in general, the sensitivities were high. The most influential factor on the efficiency of TB detection in Spain was, by far, the frequency of routine controls, followed by the sensitivity of the test used. In a context of reduced funding for cattle TB eradication, the frequency of testing should be adapted based on risk-based surveillance strategies, i.e. efforts should focus on herds more likely to be infected, but also in herds more likely to infect other herds. While slaughterhouse surveillance seems a cost-effective strategy, the use of pre-movement testing at least in areas of low incidence should be further evaluated.
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Monitoramento Epidemiológico/veterinária , Tuberculose Bovina/epidemiologia , Matadouros , Animais , Bovinos , Ácido Hialurônico , Vigilância da População , Espanha/epidemiologia , Processos Estocásticos , Meios de Transporte , Tuberculose Bovina/diagnóstico , Tuberculose Bovina/prevenção & controleRESUMO
As the phylogenetic organization of mammalian polyomaviruses is complex and currently incompletely resolved, we aimed at a deeper insight into their evolution by identifying polyomaviruses in host orders and families that have either rarely or not been studied. Sixteen unknown and two known polyomaviruses were identified in animals that belong to 5 orders, 16 genera, and 16 species. From 11 novel polyomaviruses, full genomes could be determined. Splice sites were predicted for large and small T antigen (LTAg, STAg) coding sequences (CDS) and examined experimentally in transfected cell culture. In addition, splice sites of seven published polyomaviruses were analyzed. Based on these data, LTAg and STAg annotations were corrected for 10/86 and 74/86 published polyomaviruses, respectively. For 25 polyomaviruses, a spliced middle T CDS was observed or predicted. Splice sites that likely indicate expression of additional, alternative T antigens, were experimentally detected for six polyomaviruses. In contrast to all other mammalian polyomaviruses, three closely related cetartiodactyl polyomaviruses display two introns within their LTAg CDS. In addition, the VP2 of Glis glis (edible dormouse) polyomavirus 1 was observed to be encoded by a spliced transcript, a unique experimental finding within the Polyomaviridae family. Co-phylogenetic analyses based on LTAg CDS revealed a measurable signal of codivergence when considering all mammalian polyomaviruses, most likely driven by relatively recent codivergence events. Lineage duplication was the only other process whose influence on polyomavirus evolution was unambiguous. Finally, our analyses suggest that an update of the taxonomy of the family is required, including the creation of novel genera of mammalian and non-mammalian polyomaviruses.
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Antígenos Virais de Tumores/genética , Mamíferos/virologia , Polyomavirus , Animais , Evolução Biológica , Classificação , Genes Virais , Genoma Viral , Humanos , Filogenia , Polyomavirus/classificação , Polyomavirus/genética , Polyomavirus/isolamento & purificaçãoRESUMO
Tuberculosis (TB) in animals is a re-emerging disease with a wide range of hosts that causes large economic losses in livestock. Goats are particularly susceptible to TB and, in endemic areas, vaccination may be a valuable measure to control the disease. The main aim of this study was to evaluate the efficacy of parenteral vaccination of goats with a heat-inactivated Mycobacterium bovis (HIMB) vaccine, and compare it to M. bovis Bacille Calmette-Guérin (BCG) vaccine. Twenty-four goat kids were divided in 3 groups as following: HIMB vaccinated group (n = 8), BCG vaccinated group (n = 8) and unvaccinated group (n = 8). Afterwards, goats were experimentally challenged with Mycobacterium caprae by the endobronchial route. Antigen specific interferon-γ release assays and serology were performed after vaccination and challenge. Pathological and bacteriological parameters were evaluated after necropsy at 9 weeks post-challenge (p.c.). HIMB vaccine showed similar levels of protection to BCG in terms of volume reduction of thoracic TB lesions, presence of extra-pulmonary lesions, as well as a slight reduction of bacterial load in pulmonary lymph nodes. Moreover, HIMB vaccine did not induce interferences on the interferon-γ release assay based on reagents previously developed to differentiate infected from BCG vaccinated individuals. The results indicate that HIMB is a suitable vaccine candidate for further larger-scale trials under field conditions in goats.