{"id":{"repo_id":"cambridge","oai_identifier":"oai:www.repository.cam.ac.uk:1810/368437"},"canonical_url":"https://search.dev.ndltd.org/etd/cambridge/oai:www.repository.cam.ac.uk:1810/368437","repository":{"repo_id":"cambridge","name":"Cambridge University","base_url":"https://api.repository.cam.ac.uk/server/oai/request"},"display":{"title":"The burden and control of bovine tuberculosis in endemic settings","abstract":"Bovine tuberculosis (bTB) is a major disease in cattle and also poses a public health risk due to transmission from animals to humans. The effectiveness of traditionally used strategies to control bTB, such as test-and-slaughter, varies considerably and the disease still persists in several places. Furthermore, in many countries such aggressive measures are not socioeconomically feasible and alternative approaches for controlling bTB are urgently needed. Vaccination has the potential to reduce economic and cultural barriers to controlling bTB. However, to assess the impact of potential control measures, such as vaccination, and guide policy-makers in prioritisation of interventions for infectious diseases, the burden of disease needs to be understood. Broadly, the burden of bTB can be separated into the prevalence of infection, the effect of bTB on animal health and production, risks of bTB to human health through zoonotic transmission, and the cost of control efforts and trade restrictions. However, the true burden of bTB is unknown and the actual public health risk of bTB remains unspecified in many production systems and settings. Globally, there are divergent control measures in place for bovine TB with little indication of the ideal strategy to reduce the disease burden. Simultaneously, countries without current bTB control plans in place require evidence of the disease cost and effectiveness of interventions before committing to control or elimination schemes. Therefore, in this work, the impact of vaccination on the burden of bTB in endemic countries is explored to develop an evidence-based approach for combating bTB. To achieve this, the epidemiology of bTB and available control tools are described in Chapter 1. Additionally, the epidemiological situation of bTB in India and Ethiopia is discussed as examples of endemic countries with emerging dairy markets that currently do not have any statutory surveillance or control programmes for bTB in animal populations. To explore the potential of vaccination as a control method for bTB in an endemic setting, in Chapter 2 a disease transmission model which incorporates simulated networks of cattle movements in Ethiopia was developed. The outputs of the model project the potential expansion of bTB within emerging dairy areas in Ethiopia over the next 50 years and the potential impact of vaccination on the occurrence of bTB. I find that vaccination could be a valuable tool in reducing the burden of bTB in endemic herds but would not be sufficient to eliminate bTB. Then, in Chapter 3, the burden of bTB on animal health, welfare and production is assessed through a systematic review and incorporated into the framework developed in Chapter 2 to evaluate the potential of vaccination in reducing the burden of bTB. Although several of the parameters evaluated suggested there was a burden of bTB on animal health, welfare and production, the evidence was limited and sometimes conflicting. The Chapter highlights the paucity of evidence which is essential for evaluating the benefit of any disease intervention and, as a result, importance of considering the distribution of outcomes when supporting material is scarce. In Chapter 4, the association between bovine ownership and density with human tuberculosis (TB) in India is assessed. Zoonotic tuberculosis remains under-recognised and the significance of its contribution to human tuberculosis within the country is poorly understood. I discover an association between human tuberculosis reporting, bovine density and bovine ownership in India, where buffalo density was significantly associated with an increased risk of self-reported tuberculosis in households. It is unclear whether this relates to differences in tuberculosis transmission dynamics, or perhaps an association between bovines and other unexplored confounders for tuberculosis reporting in humans. The chapter highlights the need for structured surveillance of bTB in bovines and investigation of zoonotic transmission of TB at the human-bovine interface in the country. The chapter is an adaptation of already published work (Willgert et al., 2023). In the fifth chapter, a framework for investigating the transmission history of infectious diseases is adapted to investigate who-infected-whom at the human-animal interface. Although the intention was to explore the potential patterns and rates of zoonotic transmission of TB in India, sample collection, in particular from animals, was delayed by the 2019 pandemic of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the pandemic provided an opportunity to apply the methodology to study the same question with respect to a different pathogen and animal host – the transmission of SARS-CoV-2 in humans and white-tailed deer. Using genomic data, I reconstruct the transmission history of SARS-CoV-2 in humans and deer as well as infer relative rates of transmission between species. The analysis established multiple spillover events of SARS-CoV-2 from humans to deer but there was no evidence of transmission from deer to human. Nevertheless, because of a large number of unsampled cases, spillback to humans cannot be ruled out. The extensive transmission of SARS-CoV-2 within deer populations and the low case finding rate emphasise the need for a One Health approach in surveillance for SARS-CoV-2. The results of this chapter have been published (Willgert et al., 2022). Finally, the main findings and conclusions from the studies are discussed in Chapter 6 We conclude that vaccination has potential to mitigate the burden of bTB in endemic populations but the impact on the burden of infection beyond prevalence needs to be further characterised.","abstract_html":"Bovine tuberculosis (bTB) is a major disease in cattle and also poses a public health risk due to transmission from animals to humans. The effectiveness of traditionally used strategies to control bTB, such as test-and-slaughter, varies considerably and the disease still persists in several places. Furthermore, in many countries such aggressive measures are not socioeconomically feasible and alternative approaches for controlling bTB are urgently needed. Vaccination has the potential to reduce economic and cultural barriers to controlling bTB. However, to assess the impact of potential control measures, such as vaccination, and guide policy-makers in prioritisation of interventions for infectious diseases, the burden of disease needs to be understood. Broadly, the burden of bTB can be separated into the prevalence of infection, the effect of bTB on animal health and production, risks of bTB to human health through zoonotic transmission, and the cost of control efforts and trade restrictions. However, the true burden of bTB is unknown and the actual public health risk of bTB remains unspecified in many production systems and settings. Globally, there are divergent control measures in place for bovine TB with little indication of the ideal strategy to reduce the disease burden. Simultaneously, countries without current bTB control plans in place require evidence of the disease cost and effectiveness of interventions before committing to control or elimination schemes. Therefore, in this work, the impact of vaccination on the burden of bTB in endemic countries is explored to develop an evidence-based approach for combating bTB. To achieve this, the epidemiology of bTB and available control tools are described in Chapter 1. Additionally, the epidemiological situation of bTB in India and Ethiopia is discussed as examples of endemic countries with emerging dairy markets that currently do not have any statutory surveillance or control programmes for bTB in animal populations. To explore the potential of vaccination as a control method for bTB in an endemic setting, in Chapter 2 a disease transmission model which incorporates simulated networks of cattle movements in Ethiopia was developed. The outputs of the model project the potential expansion of bTB within emerging dairy areas in Ethiopia over the next 50 years and the potential impact of vaccination on the occurrence of bTB. I find that vaccination could be a valuable tool in reducing the burden of bTB in endemic herds but would not be sufficient to eliminate bTB. Then, in Chapter 3, the burden of bTB on animal health, welfare and production is assessed through a systematic review and incorporated into the framework developed in Chapter 2 to evaluate the potential of vaccination in reducing the burden of bTB. Although several of the parameters evaluated suggested there was a burden of bTB on animal health, welfare and production, the evidence was limited and sometimes conflicting. The Chapter highlights the paucity of evidence which is essential for evaluating the benefit of any disease intervention and, as a result, importance of considering the distribution of outcomes when supporting material is scarce. In Chapter 4, the association between bovine ownership and density with human tuberculosis (TB) in India is assessed. Zoonotic tuberculosis remains under-recognised and the significance of its contribution to human tuberculosis within the country is poorly understood. I discover an association between human tuberculosis reporting, bovine density and bovine ownership in India, where buffalo density was significantly associated with an increased risk of self-reported tuberculosis in households. It is unclear whether this relates to differences in tuberculosis transmission dynamics, or perhaps an association between bovines and other unexplored confounders for tuberculosis reporting in humans. The chapter highlights the need for structured surveillance of bTB in bovines and investigation of zoonotic transmission of TB at the human-bovine interface in the country. The chapter is an adaptation of already published work (Willgert et al., 2023). In the fifth chapter, a framework for investigating the transmission history of infectious diseases is adapted to investigate who-infected-whom at the human-animal interface. Although the intention was to explore the potential patterns and rates of zoonotic transmission of TB in India, sample collection, in particular from animals, was delayed by the 2019 pandemic of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the pandemic provided an opportunity to apply the methodology to study the same question with respect to a different pathogen and animal host – the transmission of SARS-CoV-2 in humans and white-tailed deer. Using genomic data, I reconstruct the transmission history of SARS-CoV-2 in humans and deer as well as infer relative rates of transmission between species. The analysis established multiple spillover events of SARS-CoV-2 from humans to deer but there was no evidence of transmission from deer to human. Nevertheless, because of a large number of unsampled cases, spillback to humans cannot be ruled out. The extensive transmission of SARS-CoV-2 within deer populations and the low case finding rate emphasise the need for a One Health approach in surveillance for SARS-CoV-2. The results of this chapter have been published (Willgert et al., 2022). Finally, the main findings and conclusions from the studies are discussed in Chapter 6 We conclude that vaccination has potential to mitigate the burden of bTB in endemic populations but the impact on the burden of infection beyond prevalence needs to be further characterised.","abstract_has_math":false,"creators":["Willgert, Katriina"],"institution":"University of Cambridge","degree_name":"Doctor of Philosophy (PhD)","degree_level":"Doctoral","degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Conlan, Andrew"],"committee_chairs":[],"committee_members":[],"year":2023,"date_issued":"2023-10-05","date_published":"2023-10-05","updated_at":"2026-07-22T22:24:24Z","subjects":["bovine tuberculosis","control","Human-animal interface","infectious disease burden","prevention","SARS-CoV-2","vaccination","Veterinary epidemiology","Veterinary public health","zoonotic tuberculosis"],"languages":["eng"],"rights":[],"rights_urls":["https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/ac273239-4d23-4a70-87a0-2eb860143094/download","https://creativecommons.org/licenses/by/4.0/"],"identifier_entries":[{"key":"dc:creator.authoridentifier","label":"Author Identifier","values":["0000000335861997"],"render_values":[{"text":"0000-0003-3586-1997","href":"https://orcid.org/0000-0003-3586-1997","code":true}]}]},"links":{"outbound_url":"https://doi.org/10.17863/CAM.108635","outbound_label":"DOI","outbound_source":"dc:identifier.doi"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Conlan, Andrew"]},{"key":"dc:creator","label":"Author","values":["Willgert, Katriina"]},{"key":"dc:creator.authoridentifier","label":"Author Identifier","values":["0000000335861997"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.issued","label":"Date","values":["2023-10-05"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Cambridge"]},{"key":"dc:relation.isreferencedby.uri","label":"Dc Relation Isreferencedby URI","values":["https://www.repository.cam.ac.uk/handle/1810/368437"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Doctoral"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["Doctor of Philosophy (PhD)"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["bovine tuberculosis","control","Human-animal interface","infectious disease burden","prevention","SARS-CoV-2","vaccination","Veterinary epidemiology","Veterinary public health","zoonotic tuberculosis"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/ac273239-4d23-4a70-87a0-2eb860143094/download","https://creativecommons.org/licenses/by/4.0/"]},{"key":"dc:rights.embargodate","label":"Dc Rights Embargodate","values":["2027-05-16"]},{"key":"dc:rights.embargotype","label":"Dc Rights Embargotype","values":["embargo"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.doi","label":"DOI","values":["https://doi.org/10.17863/CAM.108635"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/595246fb-721f-4c21-b2e8-d733235f71a4/download"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Bovine tuberculosis (bTB) is a major disease in cattle and also poses a public health risk due to transmission from animals to humans. The effectiveness of traditionally used strategies to control bTB, such as test-and-slaughter, varies considerably and the disease still persists in several places. Furthermore, in many countries such aggressive measures are not socioeconomically feasible and alternative approaches for controlling bTB are urgently needed. Vaccination has the potential to reduce economic and cultural barriers to controlling bTB. However, to assess the impact of potential control measures, such as vaccination, and guide policy-makers in prioritisation of interventions for infectious diseases, the burden of disease needs to be understood. Broadly, the burden of bTB can be separated into the prevalence of infection, the effect of bTB on animal health and production, risks of bTB to human health through zoonotic transmission, and the cost of control efforts and trade restrictions. However, the true burden of bTB is unknown and the actual public health risk of bTB remains unspecified in many production systems and settings. Globally, there are divergent control measures in place for bovine TB with little indication of the ideal strategy to reduce the disease burden. Simultaneously, countries without current bTB control plans in place require evidence of the disease cost and effectiveness of interventions before committing to control or elimination schemes. Therefore, in this work, the impact of vaccination on the burden of bTB in endemic countries is explored to develop an evidence-based approach for combating bTB. To achieve this, the epidemiology of bTB and available control tools are described in Chapter 1. Additionally, the epidemiological situation of bTB in India and Ethiopia is discussed as examples of endemic countries with emerging dairy markets that currently do not have any statutory surveillance or control programmes for bTB in animal populations. To explore the potential of vaccination as a control method for bTB in an endemic setting, in Chapter 2 a disease transmission model which incorporates simulated networks of cattle movements in Ethiopia was developed. The outputs of the model project the potential expansion of bTB within emerging dairy areas in Ethiopia over the next 50 years and the potential impact of vaccination on the occurrence of bTB. I find that vaccination could be a valuable tool in reducing the burden of bTB in endemic herds but would not be sufficient to eliminate bTB. Then, in Chapter 3, the burden of bTB on animal health, welfare and production is assessed through a systematic review and incorporated into the framework developed in Chapter 2 to evaluate the potential of vaccination in reducing the burden of bTB. Although several of the parameters evaluated suggested there was a burden of bTB on animal health, welfare and production, the evidence was limited and sometimes conflicting. The Chapter highlights the paucity of evidence which is essential for evaluating the benefit of any disease intervention and, as a result, importance of considering the distribution of outcomes when supporting material is scarce. In Chapter 4, the association between bovine ownership and density with human tuberculosis (TB) in India is assessed. Zoonotic tuberculosis remains under-recognised and the significance of its contribution to human tuberculosis within the country is poorly understood. I discover an association between human tuberculosis reporting, bovine density and bovine ownership in India, where buffalo density was significantly associated with an increased risk of self-reported tuberculosis in households. It is unclear whether this relates to differences in tuberculosis transmission dynamics, or perhaps an association between bovines and other unexplored confounders for tuberculosis reporting in humans. The chapter highlights the need for structured surveillance of bTB in bovines and investigation of zoonotic transmission of TB at the human-bovine interface in the country. The chapter is an adaptation of already published work (Willgert et al., 2023). In the fifth chapter, a framework for investigating the transmission history of infectious diseases is adapted to investigate who-infected-whom at the human-animal interface. Although the intention was to explore the potential patterns and rates of zoonotic transmission of TB in India, sample collection, in particular from animals, was delayed by the 2019 pandemic of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the pandemic provided an opportunity to apply the methodology to study the same question with respect to a different pathogen and animal host – the transmission of SARS-CoV-2 in humans and white-tailed deer. Using genomic data, I reconstruct the transmission history of SARS-CoV-2 in humans and deer as well as infer relative rates of transmission between species. The analysis established multiple spillover events of SARS-CoV-2 from humans to deer but there was no evidence of transmission from deer to human. Nevertheless, because of a large number of unsampled cases, spillback to humans cannot be ruled out. The extensive transmission of SARS-CoV-2 within deer populations and the low case finding rate emphasise the need for a One Health approach in surveillance for SARS-CoV-2. The results of this chapter have been published (Willgert et al., 2022). Finally, the main findings and conclusions from the studies are discussed in Chapter 6 We conclude that vaccination has potential to mitigate the burden of bTB in endemic populations but the impact on the burden of infection beyond prevalence needs to be further characterised."]},{"key":"dc:format.checksum.md5","label":"Dc Format Checksum Md5","values":["ec1430d9bf191ac0ec8cf6b4430c68e6","87eda9de84448d1f82354d60eee3eb5f"]},{"key":"dc:title","label":"Title","values":["The burden and control of bovine tuberculosis in endemic settings"]}]}],"canonical_facts":{"dc:contributor.advisor":["Conlan, Andrew"],"dc:creator":["Willgert, Katriina"],"dc:creator.authoridentifier":["0000000335861997"],"dc:date.issued":["2023-10-05"],"dc:description.abstract":["Bovine tuberculosis (bTB) is a major disease in cattle and also poses a public health risk due to transmission from animals to humans. The effectiveness of traditionally used strategies to control bTB, such as test-and-slaughter, varies considerably and the disease still persists in several places. Furthermore, in many countries such aggressive measures are not socioeconomically feasible and alternative approaches for controlling bTB are urgently needed. Vaccination has the potential to reduce economic and cultural barriers to controlling bTB. However, to assess the impact of potential control measures, such as vaccination, and guide policy-makers in prioritisation of interventions for infectious diseases, the burden of disease needs to be understood. Broadly, the burden of bTB can be separated into the prevalence of infection, the effect of bTB on animal health and production, risks of bTB to human health through zoonotic transmission, and the cost of control efforts and trade restrictions. However, the true burden of bTB is unknown and the actual public health risk of bTB remains unspecified in many production systems and settings. Globally, there are divergent control measures in place for bovine TB with little indication of the ideal strategy to reduce the disease burden. Simultaneously, countries without current bTB control plans in place require evidence of the disease cost and effectiveness of interventions before committing to control or elimination schemes. Therefore, in this work, the impact of vaccination on the burden of bTB in endemic countries is explored to develop an evidence-based approach for combating bTB. To achieve this, the epidemiology of bTB and available control tools are described in Chapter 1. Additionally, the epidemiological situation of bTB in India and Ethiopia is discussed as examples of endemic countries with emerging dairy markets that currently do not have any statutory surveillance or control programmes for bTB in animal populations. To explore the potential of vaccination as a control method for bTB in an endemic setting, in Chapter 2 a disease transmission model which incorporates simulated networks of cattle movements in Ethiopia was developed. The outputs of the model project the potential expansion of bTB within emerging dairy areas in Ethiopia over the next 50 years and the potential impact of vaccination on the occurrence of bTB. I find that vaccination could be a valuable tool in reducing the burden of bTB in endemic herds but would not be sufficient to eliminate bTB. Then, in Chapter 3, the burden of bTB on animal health, welfare and production is assessed through a systematic review and incorporated into the framework developed in Chapter 2 to evaluate the potential of vaccination in reducing the burden of bTB. Although several of the parameters evaluated suggested there was a burden of bTB on animal health, welfare and production, the evidence was limited and sometimes conflicting. The Chapter highlights the paucity of evidence which is essential for evaluating the benefit of any disease intervention and, as a result, importance of considering the distribution of outcomes when supporting material is scarce. In Chapter 4, the association between bovine ownership and density with human tuberculosis (TB) in India is assessed. Zoonotic tuberculosis remains under-recognised and the significance of its contribution to human tuberculosis within the country is poorly understood. I discover an association between human tuberculosis reporting, bovine density and bovine ownership in India, where buffalo density was significantly associated with an increased risk of self-reported tuberculosis in households. It is unclear whether this relates to differences in tuberculosis transmission dynamics, or perhaps an association between bovines and other unexplored confounders for tuberculosis reporting in humans. The chapter highlights the need for structured surveillance of bTB in bovines and investigation of zoonotic transmission of TB at the human-bovine interface in the country. The chapter is an adaptation of already published work (Willgert et al., 2023). In the fifth chapter, a framework for investigating the transmission history of infectious diseases is adapted to investigate who-infected-whom at the human-animal interface. Although the intention was to explore the potential patterns and rates of zoonotic transmission of TB in India, sample collection, in particular from animals, was delayed by the 2019 pandemic of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the pandemic provided an opportunity to apply the methodology to study the same question with respect to a different pathogen and animal host – the transmission of SARS-CoV-2 in humans and white-tailed deer. Using genomic data, I reconstruct the transmission history of SARS-CoV-2 in humans and deer as well as infer relative rates of transmission between species. The analysis established multiple spillover events of SARS-CoV-2 from humans to deer but there was no evidence of transmission from deer to human. Nevertheless, because of a large number of unsampled cases, spillback to humans cannot be ruled out. The extensive transmission of SARS-CoV-2 within deer populations and the low case finding rate emphasise the need for a One Health approach in surveillance for SARS-CoV-2. The results of this chapter have been published (Willgert et al., 2022). Finally, the main findings and conclusions from the studies are discussed in Chapter 6 We conclude that vaccination has potential to mitigate the burden of bTB in endemic populations but the impact on the burden of infection beyond prevalence needs to be further characterised."],"dc:format.checksum.md5":["ec1430d9bf191ac0ec8cf6b4430c68e6","87eda9de84448d1f82354d60eee3eb5f"],"dc:identifier.doi":["https://doi.org/10.17863/CAM.108635"],"dc:identifier.uri":["https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/595246fb-721f-4c21-b2e8-d733235f71a4/download"],"dc:language":["eng"],"dc:publisher.institution":["University of Cambridge"],"dc:relation.isreferencedby.uri":["https://www.repository.cam.ac.uk/handle/1810/368437"],"dc:rights":["https://apollo8-f-pro.lib.cam.ac.uk/bitstreams/ac273239-4d23-4a70-87a0-2eb860143094/download","https://creativecommons.org/licenses/by/4.0/"],"dc:rights.embargodate":["2027-05-16"],"dc:rights.embargotype":["embargo"],"dc:subject":["bovine tuberculosis","control","Human-animal interface","infectious disease burden","prevention","SARS-CoV-2","vaccination","Veterinary epidemiology","Veterinary public health","zoonotic tuberculosis"],"dc:title":["The burden and control of bovine tuberculosis in endemic settings"],"dc:type":["Thesis"],"dc:type.qualificationlevel":["Doctoral"],"dc:type.qualificationname":["Doctor of Philosophy (PhD)"]},"updated_at":"2026-07-22T22:24:24Z"}