Publicação
Could a vaccine eradicate bovine tuberculosis in Portugal before 2025?
| Resumo: | ABSTRACT - Introduction: Bovine tuberculosis (bTB) is a zoonotic disease, which affects cattle. In Portugal, bTB prevalence is low and the country aims to eradicate the disease by 2025. However, the presence of wildlife reservoirs and the long latent stage complicates this objective. This work aims to understand the impact of Bacillus Calmette-Guérin (BCG) in the control of bTB in Portugal through mathematical modelling and, whether it would be possible to eradicate the disease before 2025. Methods: A mathematical model (Susceptible- Exposed- Infectious– Susceptible vaccinated- Exposed vaccinated- Infectious vaccinated) representing bTB transmission between cattle with the BCG vaccine was built and implemented in R. Parameters were abstracted from the literature and data from the Portuguese bTB eradication programme. The impact of BCG on bTB was simulated using different culling and vaccination rates. The final outputs were the basic reproduction number (R0), the number of infectious animals, the bTB prevalence and the disease reduction. Results: When vaccination is considered, at any rate, the burden of disease is similar to the model only considering test and slaughter strategy. The only difference is the number of vaccinated infectious animals, which is higher when the vaccination rate increases and there is a slight decrease in R0. The major impact on decreasing the bTB infection burden is when the culling rate is 1 with and without vaccination. Discussion and Conclusion: The results suggest that the vaccination will not eradicate bTB before 2025. However, more research is needed to understand the impact of BCG on bTB. Further projects should explore the stochastic effects of bTB and focus on herds in high-risk areas. |
|---|---|
| Autores principais: | Esteves, Sara Maria Navalho Novo |
| Assunto: | Bovine tuberculosis Portugal Mathematical Model BCG vaccine disease eradication Tuberculose bovina Modelo matemático vacina da BCG erradicação da doença |
| Ano: | 2021 |
| País: | Portugal |
| Tipo de documento: | dissertação de mestrado |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Universidade Nova de Lisboa |
| Idioma: | inglês |
| Origem: | Repositório Institucional da UNL |
| Resumo: | ABSTRACT - Introduction: Bovine tuberculosis (bTB) is a zoonotic disease, which affects cattle. In Portugal, bTB prevalence is low and the country aims to eradicate the disease by 2025. However, the presence of wildlife reservoirs and the long latent stage complicates this objective. This work aims to understand the impact of Bacillus Calmette-Guérin (BCG) in the control of bTB in Portugal through mathematical modelling and, whether it would be possible to eradicate the disease before 2025. Methods: A mathematical model (Susceptible- Exposed- Infectious– Susceptible vaccinated- Exposed vaccinated- Infectious vaccinated) representing bTB transmission between cattle with the BCG vaccine was built and implemented in R. Parameters were abstracted from the literature and data from the Portuguese bTB eradication programme. The impact of BCG on bTB was simulated using different culling and vaccination rates. The final outputs were the basic reproduction number (R0), the number of infectious animals, the bTB prevalence and the disease reduction. Results: When vaccination is considered, at any rate, the burden of disease is similar to the model only considering test and slaughter strategy. The only difference is the number of vaccinated infectious animals, which is higher when the vaccination rate increases and there is a slight decrease in R0. The major impact on decreasing the bTB infection burden is when the culling rate is 1 with and without vaccination. Discussion and Conclusion: The results suggest that the vaccination will not eradicate bTB before 2025. However, more research is needed to understand the impact of BCG on bTB. Further projects should explore the stochastic effects of bTB and focus on herds in high-risk areas. |
|---|