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Free-living amoebae (FLA) are described as environmental reservoirs for some bacteria able to resist their phagocytosis. In the environment, the fate of Mycobacterium bovis (Mbo) and Mycobacterium avium subsp. paratuberculosis (Map) responsible for bovine tuberculosis and paratuberculosis, respectively, remains poorly understood and is considered potentially problematic in the eradication and control of these diseases. We hypothesize that FLA may play a role in the persistence of Mbo and Map in the environment. In this study, 90 samples were collected from herds affected by one or both diseases to investigate the diversity of amoeba and their associated bacteria. Metabarcoding analyses revealed that Acanthamoeba, Copromyxa, Naegleria, and Vermamoeba were the most represented genera of FLA, with Pseudomonadota being the bacteria most commonly found associated with FLA. Although no Mbo and Map DNA were identified by sequencing, traces were detected by ddPCR (digital droplet PCR), specifically targeting these bacteria. In conclusion, we described a wide diversity of FLA and associated bacteria in this environment. It also suggests that Map and Mbo could be associated, even weakly, with FLA in the environment. However, this needs to be confirmed by detecting a highest amount of DNA and, if possible, cultivable Map and/or Mbo associated with these environmental FLA.

Background: Bovine tuberculosis (bTB) caused by Mycobacterium bovis is a major zoonotic disease in West Africa. In Africa, bTB is endemic in cattle with a prevalence ranging from 2% up to 18%. The disease causes significant public health risks due to unpasteurized milk and milk product consumption. In the context of the EU-PRISMA project, which promotes research and innovation for productive, resilient, and healthy agropastoral systems in West Africa, a cross-sectional survey was conducted in dairy herds from Mali and Niger to assess animal, herd, and within-herd bTB prevalence, as well as to identify animal risk factors and predictors of bTB herd status. Method and principal findings: A random cross-sectional survey on dairy cattle farms using comparative intradermal tuberculin test and epidemiological inquiry was performed in four regions of Mali (Bamako, Koulikoro, Mopti, and Sikasso) and three regions of Niger (Tahoua, Dosso, and Tillabéry). Herd and animal prevalence of bTB and within-herd prevalence were significantly higher in Mali (especially in Bamako and Koulikoro) than in Niger. Several risk factors were significantly associated with animals positive to bTB, i.e., the region where animals live, the age range from 3 to 7 years old, and female animals. In addition, in regions with higher bTB prevalence, the herd with slaughtering of animals in the farm and the herd with the presence of an animal assembly area were associated with the most unfavorable status of a herd with regards to bTB. Moreover, the average and the median annual economic losses of bTB at animal level were estimated at €262 and €137 respectively, with large variability depending on the farm (between €46 and €838). Conclusion and significance: This survey provides useful data on bTB epidemiology and economical losses in Mali and Niger and urges for improvement of surveillance systems and prevention and control strategies. Cost-benefit, return of investment, or similar analyses are strongly recommended to help with decision making.

Mycobacterium bovis bacille Calmette-Guérin (BCG), an experimental vaccine designed to protect cattle from bovine tuberculosis, was administered for the first time to a newborn baby in Paris in 1921. Over the past century, BCG has saved tens of millions of lives and has been given to more humans than any other vaccine. It remains the sole tuberculosis vaccine licensed for use in humans. BCG provides long-lasting strong protection against miliary and meningeal tuberculosis in children, but it is less effective for the prevention of pulmonary tuberculosis, especially in adults. Evidence mainly from the past two decades suggests that BCG has non-specific benefits against non-tuberculous infections in newborn babies and in older adults, and offers immunotherapeutic benefit in certain malignancies such as non-muscle invasive bladder cancer. However, as a live attenuated vaccine, BCG can cause localised or disseminated infections in immunocompromised hosts, which can also occur following intravesical installation of BCG for the treatment of bladder cancer. The legacy of BCG includes fundamental discoveries about tuberculosis-specific and non-specific immunity and the demonstration that tuberculosis is a vaccine-preventable disease, providing a foundation for new vaccines to hasten tuberculosis elimination.

Quantifying pathogen transmission in multi-host systems is difficult, as exemplified in bovine tuberculosis (bTB) systems, but is crucial for control. The agent of bTB, Mycobacterium bovis, persists in cattle populations worldwide, often where potential wildlife reservoirs exist. However, the relative contribution of different host species to bTB persistence is generally unknown. In Britain, the role of badgers in infection persistence in cattle is highly contentious, despite decades of research and control efforts. We applied Bayesian phylogenetic and machine-learning approaches to bacterial genome data to quantify the roles of badgers and cattle in M. bovis infection dynamics in the presence of data biases. Our results suggest that transmission occurs more frequently from badgers to cattle than vice versa (10.4x in the most likely model) and that within-species transmission occurs at higher rates than between-species transmission for both. If representative, our results suggest that control operations should target both cattle and badgers. Disease-causing microbes that infect more than one type of animal can be difficult to control. This is especially true when they infect wildlife. For example, Mycobacterium bovis is a bacterium that causes tuberculosis in tens of thousands of cattle in Britain every year and also infects badgers and other wildlife. Controlling the infections in cattle is essential, as it helps prevent the bacteria from infecting humans, improves cattle welfare and reduces the substantial costs to the livestock industry. Analysing the relatedness of M. bovis genomes from infected cattle and badgers may help scientists work out how often badgers infect cattle and vice versa. Scientists have collected data and M. bovis samples from infected badgers in Woodchester Park, in England, for over three decades. Using these data and additional information about M. bovis infecting nearby cattle may help scientists learn how the bacteria spreads and how to stop it. Now, Crispell et al. show that complex patterns of contact between cattle and badgers likely drive the persistence of tuberculosis in cattle, also known as bovine tuberculosis. In three separate analyses, Crispell et al. compared the genomes of M. bovis found in cattle and badgers, the animals' locations, when they were infected, and whether they could have been in contact. The analyses found that M. bovis was likely to have been transmitted more frequently from badgers to cattle rather than from cattle to badgers. They also showed that transmission within each species happened more often than transmission between species. If these results are confirmed by other studies, they may help scientists develop better strategies for controlling tuberculosis in British cattle. In particular, controversial control strategies – such as badger culls – could be more targeted to better combat tuberculosis in cattle but have less of an impact on badgers. These insights might also aid control efforts in other countries where bovine tuberculosis is a problem and an important source of human tuberculosis.

Mycobacterium bovis ( M . bovis) is a causative agent of bovine tuberculosis, a significant source of morbidity and mortality in the global cattle industry. The Randomised Badger Culling Trial was a field experiment carried out between 1998 and 2005 in the South West of England. As part of this trial, M . bovis isolates were collected from contemporaneous and overlapping populations of badgers and cattle within ten defined trial areas. We combined whole genome sequences from 1,442 isolates with location and cattle movement data, identifying transmission clusters and inferred rates and routes of transmission of M . bovis . Most trial areas contained a single transmission cluster that had been established shortly before sampling, often contemporaneous with the expansion of bovine tuberculosis in the 1980s. The estimated rate of transmission from badger to cattle was approximately two times higher than from cattle to badger, and the rate of within-species transmission considerably exceeded these for both species. We identified long distance transmission events linked to cattle movement, recurrence of herd breakdown by infection within the same transmission clusters and superspreader events driven by cattle but not badgers. Overall, our data suggests that the transmission clusters in different parts of South West England that are still evident today were established by long-distance seeding events involving cattle movement, not by recrudescence from a long-established wildlife reservoir. Clusters are maintained primarily by within-species transmission, with less frequent spill-over both from badger to cattle and cattle to badger.

Transcription activator-like effector nuclease (TALEN)-mediated genome modification has been applied successfully to create transgenic animals in various species, such as mouse, pig, and even monkey. However, transgenic cattle with gene knockin have yet to be created using TALENs. Here, we report site-specific knockin of the transcription activator-like effector (TALE) nickase-mediated SP110 nuclear body protein gene ( SP110 ) via homologous recombination to produce tuberculosis-resistant cattle. In vitro and in vivo challenge and transmission experiments proved that the transgenic cattle are able to control the growth and multiplication of Mycobacterium bovis , turn on the apoptotic pathway of cell death instead of necrosis after infection, and efficiently resist the low dose of M . bovis transmitted from tuberculous cattle in nature. In this study, we developed TALE nickases to modify the genome of Holstein–Friesian cattle, thereby engineering a heritable genome modification that facilitates resistance to tuberculosis. Significance Bovine tuberculosis is a chronic infectious disease that affects a broad range of mammalian hosts. It is a serious threat to agriculture in many less-developed countries. In this study, we introduced a mutation to the FokI of the right hand of wild-type transcription activator-like effector nuclease and established a transcription activator-like effector nickase system that creates single-strand breaks in the genome. Then we used this system to add the mouse gene SP110 to a specific location in the bovine genome and created transgenic cattle with increased resistance to tuberculosis. Our results contribute to the control and prevention of bovine tuberculosis and provide a previously unidentified insight into breeding animals for disease resistance.

Bovine tuberculosis (BTB) is a widespread zoonosis in developing countries but has received little attention in sub-Saharan Africa, especially in Niger. Recent investigations confirmed the high incidence of the disease in cattle slaughtered in an abattoir in Niamey. The fact that most of the animals in which M. bovis has been identified were from the rural area of Torodi implied the existence of a probable source of BTB in this region. This study aimed to determine the prevalence of BTB infection in cattle and to identify risk factors for infection in human and cattle populations in Torodi. A survey was carried out at the level of households keeping livestock (n = 51). The questionnaire was related to the potential risk factors and the presence of clinical signs of TB both in animals and humans. Comparative Intradermal Tuberculin Test was conducted to determine the TB status in cattle (n = 393). The overall apparent individual animal prevalence of tuberculin reactors was 3.6% (CI: 95%, 1.9-5.9), whereas the individual true prevalence was estimated at 0.8% (CI: 95%, 0.0-5.0). Using a multivariate logistic regression analysis and a classification tree analysis, the only household level risk factor that significantly influenced the presence of BTB in cattle was the presence of animals coughing in the herd (OR = 4.7, 95% CI: 1.12-19.71, p-value = 0.034). The lack of the practice of quarantine was borderline significant (OR = 4.2, 95% CI: 0.96-18.40, p-value = 0.056). The study confirmed that BTB is endemic in cattle in Torodi and the risk of the transmission of the disease to humans is potentially high. For the control of the disease in livestock, slaughtering of infected animals and the compensation of the owners is needed. Collaboration between the veterinary and the medical sectors, in the diagnosis, monitoring, prevention and control of BTB is strongly encouraged.

Bovine tuberculosis (bTB) is a disease of cattle that is transmitted through direct contact with an infected animal or ingestion of contaminated food. A mixed-methods study was conducted in two districts of Zambia, Lundazi and Monze, from December 2021 to June 2022. A cross-sectional survey with 280 respondents, five focus group discussions, and five key informant interviews were conducted. Descriptive statistics were used to analyze quantitative data using R software, while qualitative data was analyzed using Nvivo and content analysis. Social and cultural practices were reported to significantly contribute to bTB transmission with risky behaviors including the consumption of undercooked meat and unpasteurized milk, and inadequate protective measures during cattle slaughtering. Overall, 75.3% of male and 70.3% of female respondents expressed a poor level of awareness of bTB transmission. Among cattle farmers, 85.7% lacked formal education, resulting in low knowledge levels, with 99.5% expressing poor awareness. Additionally, findings revealed that 99.5% of cattle farmers had poor awareness of bTB, human doctors/clinicians, and veterinary/para-veterinarians had 100% excellent knowledge. Abattoir workers had good knowledge at 78.3% and cattle businessmen had a fair knowledge level at 96.4%. Overall, bTB awareness varied across occupations, with human and animal healthcare professionals being the most knowledgeable. Our study found low levels of awareness and misperception about bTB among cattle farmers. Awareness varied across professionals with educated individuals being more knowledgeable. The consumption of undercooked meat and raw milk highlighted these knowledge gaps. Therefore, it is crucial to conduct public health campaigns to raise awareness about bTB causes, sources of infection, and control measures.

Pathogen interactions arising during coinfection can exacerbate disease severity, for example when the immune response mounted against one pathogen negatively affects defense of another. It is also possible that host immune responses to a pathogen, shaped by historical evolutionary interactions between host and pathogen, may modify host immune defenses in ways that have repercussions for other pathogens. In this case, negative interactions between two pathogens could emerge even in the absence of concurrent infection. Parasitic worms and tuberculosis (TB) are involved in one of the most geographically extensive of pathogen interactions, and during coinfection worms can exacerbate TB disease outcomes. Here, we show that in a wild mammal natural resistance to worms affects bovine tuberculosis (BTB) severity independently of active worm infection. We found that worm-resistant individuals were more likely to die of BTB than were nonresistant individuals, and their disease progressed more quickly. Anthelmintic treatment moderated, but did not eliminate, the resistance effect, and the effects of resistance and treatment were opposite and additive, with untreated, resistant individuals experiencing the highest mortality. Furthermore, resistance and anthelmintic treatment had nonoverlapping effects on BTB pathology. The effects of resistance manifested in the lungs (the primary site of BTB infection), while the effects of treatment manifested almost entirely in the lymph nodes (the site of disseminated disease), suggesting that resistance and active worm infection affect BTB progression via distinct mechanisms. Our findings reveal that interactions between pathogens can occur as a consequence of processes arising on very different timescales.

Mycobacterium orygis ( M. orygis ), a member of the Mycobacterium tuberculosis complex, has emerged as an important cause of animal and human tuberculosis in South Asia. Despite the widespread prevalence of bovine tuberculosis (bTB) in India and the major role of over 100 million Indian water buffaloes in dairy production, the pathological and epidemiological features of M. orygis infection in buffaloes are largely unexplored. A closed herd of 279 female water buffaloes in Haryana, India, was screened for bTB by single intradermal cervical tuberculin skin (SCT) test, the comparative cervical tuberculin (CCT) test, and the interferon gamma release assay (IGRA). Detailed post-mortem examinations, cultural isolation, Polymerase Chain Reaction, and Whole Genome Sequencing were methodically performed on reactor buffaloes. The screening identified 26 animals as reactors by SCT. Of these, 20 were confirmed positive for bTB with both CCT and IGRA. Among the 15 reactor animals examined, gross pathological lesions suggestive of bTB were observed in 13 animals, while histopathological lesions in 14 animals. Molecular analyses confirmed the presence of MTBC in nine animals, with eight identified as M. orygis infections and one with mixed infection. Notably, two genetically distinct clusters of M. orygis suggestive multiple introductions into the herd. The study reveals significant pathological and microbiological complexities in bTB infections by M. orygis in Indian water buffaloes. It underscores a need for expanded research, improved surveillance, and introduction of targeted control measures to eliminate bTB in this major farmed animal species.