Mycobacterium bovis and M. caprae in Bulgaria: insight into transmission and phylogeography gained through whole-genome sequencing.

BACKGROUND: This study aimed to characterize recent Mycobacterium bovis/M. caprae isolates from Bulgaria by whole-genome sequencing (WGS) to gain a first insight into their molecular diversity, transmission, and position within the global phylogeography of this important zoonotic species. RESULTS: The isolates were obtained from cattle in diverse locations of Bulgaria in 2015-2020 and were identified by microbiological and PCR assays. WGS data were used for phylogenetic analysis that also included M. bovis global dataset. Thirty-seven M. bovis/caprae isolates from Bulgaria were studied and 34 of them were SNP genotyped. The isolates were subdivided into 3 major phylogenetic groups. Type Mbovis-13 (Eu2 complex [western Europe and northern Africa]) included one isolate. Mbovis-37 type included 5 isolates outside of known clonal complexes. The Bulgarian M. caprae isolates formed a sub-group within the Mcaprae-27B cluster which also included 22 M. caprae isolates from Poland, Spain, Germany, and the Republic of Congo. The Bulgarian M. caprae isolates share their latest common ancestors with Spanish isolates. The Mbovis-37 group shares a distant common ancestor (pairwise distance 22-29 SNPs) with an isolate from Poland but was very distant (> 200 SNPs) from the rest of the tree. The Mbovis-13 group shares a common ancestor with two human isolates from Germany. Phylogeographically, both M. bovis clades had limited circulation in northeastern Bulgaria while the majority of the studied isolates (M. caprae) were from central and western provinces. A phylogenetic network-based analysis demonstrated that 11 Bulgarian isolates were separated by 1 to 6 SNPs within four clusters, mostly forming pairs of isolates. CONCLUSION: The obtained WGS analysis positioned the Bulgarian isolates within the global phylogeography of M. bovis/M. caprae. Hypothetically, the observed phylogenetic diversity may not have resulted from livestock trade routes, but instead may reflect the deeply rooted M. bovis/M. caprae phylogeography of Europe. A high level of genetic divergence between the majority of the studied isolates suggests limited active transmission of bTB in Bulgaria during the survey period. At the same time, a possibility of the endemic presence of circulating bTB strains in the form of the latent persistent disease cannot be ruled out.

Mycobacterial Infections in Invasive Turtle Species in Poland.

Over the last 30 years, the number of invasive turtle species living in the wild has significantly increased in Poland. This proliferation carries many threats, which mainly include the displacement of native species of animals from their natural habitats. Turtles can also be reservoirs for pathogens, including bacteria from the Mycobacterium genus. In order to confirm or rule out the presence of acid-fast mycobacteria in the population of invasive turtle species, samples from carapace, plastron, internal organs and mouth cavity swabs from 125 animals were tested. Twenty-eight mycobacterial strains were isolated in culture, which were classified as atypical following multiplex-PCR reactions. The GenoType Mycobacterium Common Mycobacteria (CM) test, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, PCR-restriction fragment length polymorphism (PRA)-hsp65 and DNA sequencing were used to identify the species of isolates. Of the 28 strains, 11 were identified as M. fortuitum, 10 as M. chelonae, 3 as M. avium ssp. avium, 2 as M. nonchromogenicum and 1 each of M. neoaurum and M. scrofulaceum. The results of the research will also strengthen the understanding that these animals can be vectors for pathogens when living in the wild.

The Eradication of M. Caprae Tuberculosis in Wild Boar (Sus Scrofa) in the Bieszczady Mountains, Southern Poland - An Administrative Perspective.

Introduction: Animal tuberculosis (TB) is a zoonotic disease caused by acid-fast bacteria belonging to the Mycobacterium tuberculosis complex (MTBC). Both animals and humans are susceptible to infection by the MTBC. Interspecies transmission is also possible, including to livestock and humans. In the years 1997-2013, many tuberculosis cases were recorded in European bison in the Bieszczady Mountains; more alarmingly, TB was also recorded in wild boar in the years 2013-2020. Material and Methods: In the years 2013-2020, 104 wild boar from the Bieszczady Mountains were tested for TB through necropsy, mycobacterial culture, strain identification and spoligotyping. Results: The microbiological examination confirmed TB in 46 wild boar; these infections were identified as M. caprae, spoligotype SB2391. Conclusion: Free-living European bison are at risk of TB infection from wild boar carrying M. caprae. This situation also poses a risk to local cattle. There is a need for further activities aimed at monitoring the disease, preventing further transmission, and minimising the risk to public health.

Ten Years of Animal Tuberculosis Monitoring in Free-Living European Bison (Bison bonasus) in Poland.

In the period 1996-2012, two outbreaks of animal tuberculosis were noted in the population of free-living European bison (Bison bonasus caucasicus) in the Bieszczady Mountains, Southern Poland. As the European bison is an endangered species and particularly susceptible to tuberculosis, not to mention a national icon, the decision was made to test all deceased bison for TB in Poland. The screened bison were obtained by elimination due to poor health or natural death. A total of 159 European bison have been examined over the last 10 years. The individuals came from four regions of Poland (Bialowieza Forest, Bieszczady Mountains, Borecka Forest, Knyszynska Forest), not only from the area where tuberculosis is still endemic. Mycobacterium bovis and Mycobacterium avium spp. hominisuis were identified in two different herds. The isolation of M. bovis from European bison was the first case described in Poland. So far, the only causative agent of tuberculosis identified in European bison in Poland, both in the wild and in captive herds, was Mycobacterium caprae. The isolated M. bovis spoligotype has not previously been registered in international spoligotype databases so far. The obtained results highlight the need to monitor TB in European bison in Poland.

Infection of a Free-Living Wild Boar (Sus scrofa) with a Bacterium from the Mycobacterium kansasii Complex.

The most numerous group of bacteria in the genus Mycobacterium is the nontuberculous mycobacteria. Currently, over 200 species of bacteria have been classified as belonging to this group, of which approximately 30 are pathogenic to humans and animals. Mycobacterium kansasii complex numbers among these pathogenic species. The submandibular lymph nodes of a wild boar shot by a hunter were examined in order to confirm or exclude infection with bacteria of the genus Mycobacterium. In culture, a bacterial isolate was obtained after 12 days of incubation on Petragnani and Stonebrink media. A multiplex PCR clearly indicated that the isolate was a nontuberculous mycobacterium. The results of species identification attempts via both molecular biology methods and mass spectrometry confirmed that the isolated strain belonged to MKC. The described case of a wild boar infection with MKC is the first documented case in Poland and only the second in Europe, and in confirming the presence of this pathogen among free-living animals, this report implies that MKC is of great concern. Our research elucidates some specifics of wild boar mycobacteriosis and may be used to instill awareness in the public of the dangers of dressing hunt prey or consuming its meat in ignorance of safe procedures, which can contribute to the transmission of the pathogen to humans.

Pulmonary mycobacteriosis of sitatunga antelope caused by M. avium ssp. hominissuis.

INTRODUCTION AND OBJECTIVE: Mycobacteriosis are diseases caused by acid-fast mycobacteria other than M. leprae and tuberculous mycobacteria. Animal mycobacteriosis is often caused by M. avium ssp. hominissuis. Many species of animals are susceptible to infection with this bacterium, even those kept in Zoological Gardens. The aim of the study was to determine the species of bacterium responsible for causing the disease in the tested animals. MATERIAL AND METHODS: Tissue samples of two male sitatunga antelopes (Tragelaphus spekii) were analyzed. Lymph node and lung samples were subjected to anatomical examination and Ziehl-Neelsen staining. Real-time PCR was performed to confirm or rule out tuberculosis mycobacteria infection. In order to isolate the bacterial strain, tissue samples were inoculated on both solid and liquid media. HainLifescience CM tests, mass spectrometry and New Generation Sequencing were used to determine the mycobacterial species. RESULTS: Results showed that atypical mycobacteria are responsible for the antelope disease. The results of the HainLifescience CM test and mass spectrometry indicated that the mycobacterium responsible for causing mycobacteriosis was M. avium. New Generation Sequencing helped to identified a subspecies that was M. avium ssp. hominissuis. CONCLUSIONS: The sitatunga antelope is an animal susceptible to infection by M. avium ssp. hominissuis. Considering the wide range of hosts and the easiness of interspecies transmission of the pathogen, as well as its zoonotic nature, the mycobacteriosis induced by this microorganism should not be underestimated.

The Potential Risk of International Spread of Mycobacterium Bovis Associated with Movement of Alpacas.

Introduction: The study highlights the transboundary nature of tuberculosis (TB) in alpacas and the failure of current ante-mortem testing protocols (the tuberculin skin and Enferplex Camelid TB tests) to identify TB-free alpaca herds and individuals for export. Our research and the available literature indicate that the alpaca (Vicugna pacos) is extremely susceptible to Mycobacterium bovis infection, and that testing periodicity fails to take into account that animals do not manifest disease symptoms for a long time. The skin test failed to identify Mycobacterium bovis infection in two alpacas prior to their movement from the UK to Poland. The animals were purchased by a breeding centre in Poland, and were then shown at an international animal exhibition. The last owner of the alpacas before their deaths from TB bought the infected animals unwittingly in order to run rehabilitation activities with disabled children on his farm. Material and Methods: Thoracic lymph node, lung and liver tissue samples obtained at necropsy were examined histopathologically after Ziehl-Neelsen staining. Tissue samples were homogenised and mycobacteria present there were cultured on Stonebrink's medium during a 6-week incubation. A commercial test using polymorphism of the chromosomal direct repeat region provided species identification and additional identification was by spacer oligonucleotide typing and mycobacteria interspersed repetitive unit-variable number tandem repeat analysis with a gel electrophoresis protocol. Results: The microbiological examination confirmed multiorgan TB caused by the SB0666 spoligotype of Mycobacterium bovis. Conclusion: Due to the suboptimal performance of current diagnostic tests for TB in alpacas, there is a risk that infected animals may be moved unwittingly. A risk of TB spread associated with the international movement of alpacas is implied by this study.

Mycobacterium bovis Transmission between Cattle and a Farmer in Central Poland.

INTRODUCTION: Zoonoses have recently become an increasing public health problem. Zoonoses are estimated to account for 60% of all emerging infectious diseases. One particularly important zoonosis is human tuberculosis, especially tuberculosis due to Mycobacterium bovis (M. bovis), which is naturally resistant to pyrazinamide (PZA). MATERIAL AND METHODS: The patient had a pulmonary form of tuberculosis accompanied by a cough and fever. At the same time, the disease was also confirmed in 20 out of 25 cattle on the farm. The clinical specimen (sputum) was examined in accordance with the European Union (EU) laboratories' methodology. Tissue materials from cattle were verified in the National Veterinary Research Institute (NVRI), in the Bovine tuberculosis (BTB) Reference Laboratory, Pulawy, Poland and tested in accordance with the guidelines for the laboratory diagnosis of BTB. RESULTS: All M. bovis isolates represented one spoligotype, SB0120. The results of mycobacterial interspersed repetitive unit variable number tandem repeat (MIRU-VNTR) evaluation showed the same genetic pattern. CONCLUSIONS: Findings from this study suggest the first confirmed interspecific transmission of Mycobacterium bovis, between a farmer and his cattle, in Poland. Present findings support the increasing concern regarding zoonotic TB that has been highlighted elsewhere.

Molecular Characterisation of the Mycobacterium Bovis Causing Bovine Tuberculosis Outbreaks in Poland.

INTRODUCTION: Since 2009, Poland has been recognised as a country officially free of bovine tuberculosis (bTB), although in each year of the last five there were from 8 to 18 outbreaks of the disease. In 2008-2016, the largest number of cattle infected with bovine mycobacteria were eliminated in the Masovian Province (the central region of Poland) and the largest number of outbreaks of this zoonosis were recorded in this area. The close proximity of farms where bTB was found led to the suspicion that tuberculosis could have been transmitted between the affected herds. The aim of the study was the molecular characterisation of the pertinent M. bovis/caprae strains and determination of the epidemiological relationship of various bTB outbreaks. MATERIAL AND METHODS: The material for microbiological tests came from 119 cattle (Bos taurus) from nine herds located in five provinces, neighbouring the Masovian Province. RESULTS: Laboratory tests of tissue material gave results confirming tuberculosis in 54 (45%) animals. All strains belonged to the Mycobacterium bovis species. A two-step analysis of genetic affinity allowed 50 strains to be identified as phylogenetically closely related and separated between three genetic clusters consisting of 2 to 27 strains. CONCLUSION: Based on the results of genotyping, bTB outbreaks were found in three herds, and three transmission chains were identified among these herds.

Transboundary tuberculosis: Importation of alpacas infected with Mycobacterium bovis from the United Kingdom to Poland and potential for serodiagnostic assays in detecting tuberculin skin test false-negative animals.

The present study highlights the transboundary nature of tuberculosis (TB) in alpacas and the failure of current antemortem testing protocols to identify TB-free alpaca herds and individuals for exportation. The tuberculin skin test (TST) failed to identify Mycobacterium bovis-infected animals prior to movement from the United Kingdom (UK) to Poland. This study describes the use of four serological assays [Enferplex Camelid TB, dual-path platform (DPP) VetTB and BovidTB assays, and multi-antigen print immunoassays (MAPIAs)] to detect TB in an alpaca herd with negative TST results. The breeding in Poland purchased alpacas for several years from the UK with the last group arriving in May 2018. In July 2018, two sick alpacas from the centre were hospitalized in a veterinary clinic and both died of TB a few weeks later. In November 2018, 20 alpacas remaining in this M. bovis-affected herd were euthanized and samples were collected. The study population included 20 M. bovis-infected and 20 uninfected alpacas, but only 15 infected animals were tested by all serology tests. The DPP VetTB and DPP BovidTB assays detected antibodies in 14 of the 20 infected alpacas, with results confirmed by MAPIA, and in none (MAPIA and DPP BovidTB) or one (DPP VetTB) of the 20 uninfected animals. None of the infected alpacas tested positive using the Enferplex assay. In addition, the group included three orphans and two cria-dam pairs, which provided an opportunity to analyse immune aspects of cria-mother relationships in this herd. The results suggest high susceptibility of this host species to M. bovis infection and rapid progression to disease. The serological tests used in this study offer useful tools for the detection of M. bovis infection in TST and Enferplex test non-reactive alpacas. These tests should be further evaluated for implementation into TB management and control strategies for camelid species.

A case of bovine tuberculosis in pigs in Poland - a country free from the disease.

INTRODUCTION: Bovine tuberculosis is a chronic contagious disease caused by Mycobacterium bovis or Mycobacterium caprae. Before widespread action conducted in Poland between 1959-1975 to combat bovine tuberculosis (BTB), about 40% of all tuberculosis cases in pigs was caused by the bovine bacillus. At the present time, correctly carried out, long-term control of cattle has resulted in cases of bovine tuberculosis in pigs and humans being extremely rare and sporadic. In pigs, tuberculosis is most often caught in a slaughterhouse during slaughter. MATERIAL AND METHODS: Samples came from pigs kept on the farm. Traditional bacteriological methods on solid media (Stonebrink, LJ with pyruvate) supported by the semi-automatic, liquid indicative culture method (MGIT) and PCR test were applied in targeted studies. The GenoType Mycobacterium MTBC and CM tests (Hain Lifescience, Germany) were used to additionally confirm that isolated strains classification was used. RESULTS: Strains of mycobacteria were isolated from all examined pigs. Mycobacterium bovis was determined by real time PCR and Hain Genotype methods. CONCLUSIONS: In order to effectively fight against BTB, all animals on farms should be tested, regardless of species, while the milk of suspected cows should be utilized without being used for feed. It is important to adapt the current legal regulations to the current epidemiological situation.

Badgers as a potential source of bovine tuberculosis - first studies in Poland.

Since 2009, Poland has been recognized as a country officially free of bovine tuberculosis (BTB). However, new outbreaks are each year quoted. In many countries it has been shown that badgers (Meles meles) are a vector of Mycobacterium bovis/caprae (M.bovis/caprae) and a source of bovine tuberculosis for many domestical species, mainly for cattle. The aim of the presented study was to determine, for the first time in Poland, the occurrence of tuberculosis in badgers in areas where the disease occurs in cattle. Tissue samples were examined by classical microbiology methods, mycobacteria growth indicator tube (MGIT), and real time PCR. A total of 155 samples from 31 badgers were examined. In any case Mycobacterium bovis/caprae infection has not been diagnosed. This indicates that badgers probably are not a vector of bovine tuberculosis in Poland.