Modeling Marek's disease virus transmission: A framework for evaluating the impact of farming practices and evolution
Marek's disease virus (MDV) is a pathogen of chickens whose control has twice been undermined by pathogen evolution. Disease ecology is believed to be the main driver of this evolution, yet mathematical models of MDV disease ecology have never been confronted with data to test their reliability...
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doaj-a48f4756e97f442e8028c3299458371c2020-11-24T22:56:20ZengElsevierEpidemics1755-43652018-06-01238595Modeling Marek's disease virus transmission: A framework for evaluating the impact of farming practices and evolutionDavid A. Kennedy0Patricia A. Dunn1Andrew F. Read2Center for Infectious Disease Dynamics, Departments of Biology and Entomology, The Pennsylvania State University, University Park, PA, USA; Corresponding author.Animal Diagnostics Laboratory, Department of Veterinary and Biomedical Sciences, The Pennsylvania State University, University Park, PA, USACenter for Infectious Disease Dynamics, Departments of Biology and Entomology, The Pennsylvania State University, University Park, PA, USAMarek's disease virus (MDV) is a pathogen of chickens whose control has twice been undermined by pathogen evolution. Disease ecology is believed to be the main driver of this evolution, yet mathematical models of MDV disease ecology have never been confronted with data to test their reliability. Here, we develop a suite of MDV models that differ in the ecological mechanisms they include. We fit these models with maximum likelihood using iterated filtering in ‘pomp’ to data on MDV concentration in dust collected from two commercial broiler farms. We find that virus dynamics are influenced by between-flock variation in host susceptibility to virus, shedding rate from infectious birds, and cleanout efficiency. We also find evidence that virus is reintroduced to farms approximately once per month, but we do not find evidence that virus sanitization rates vary between flocks. Of the models that survive model selection, we find agreement between parameter estimates and previous experimental data, as well as agreement between field data and the predictions of these models. Using the set of surviving models, we explore how changes to farming practices are predicted to influence MDV-associated condemnation risk (production losses at slaughter). By quantitatively capturing the mechanisms of disease ecology, we have laid the groundwork to explore the future trajectory of virus evolution. Keywords: Marek's disease virus, Poultry, Disease ecology, Model comparison, Plug-and-play modelhttp://www.sciencedirect.com/science/article/pii/S1755436517301330 |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
David A. Kennedy Patricia A. Dunn Andrew F. Read |
spellingShingle |
David A. Kennedy Patricia A. Dunn Andrew F. Read Modeling Marek's disease virus transmission: A framework for evaluating the impact of farming practices and evolution Epidemics |
author_facet |
David A. Kennedy Patricia A. Dunn Andrew F. Read |
author_sort |
David A. Kennedy |
title |
Modeling Marek's disease virus transmission: A framework for evaluating the impact of farming practices and evolution |
title_short |
Modeling Marek's disease virus transmission: A framework for evaluating the impact of farming practices and evolution |
title_full |
Modeling Marek's disease virus transmission: A framework for evaluating the impact of farming practices and evolution |
title_fullStr |
Modeling Marek's disease virus transmission: A framework for evaluating the impact of farming practices and evolution |
title_full_unstemmed |
Modeling Marek's disease virus transmission: A framework for evaluating the impact of farming practices and evolution |
title_sort |
modeling marek's disease virus transmission: a framework for evaluating the impact of farming practices and evolution |
publisher |
Elsevier |
series |
Epidemics |
issn |
1755-4365 |
publishDate |
2018-06-01 |
description |
Marek's disease virus (MDV) is a pathogen of chickens whose control has twice been undermined by pathogen evolution. Disease ecology is believed to be the main driver of this evolution, yet mathematical models of MDV disease ecology have never been confronted with data to test their reliability. Here, we develop a suite of MDV models that differ in the ecological mechanisms they include. We fit these models with maximum likelihood using iterated filtering in ‘pomp’ to data on MDV concentration in dust collected from two commercial broiler farms. We find that virus dynamics are influenced by between-flock variation in host susceptibility to virus, shedding rate from infectious birds, and cleanout efficiency. We also find evidence that virus is reintroduced to farms approximately once per month, but we do not find evidence that virus sanitization rates vary between flocks. Of the models that survive model selection, we find agreement between parameter estimates and previous experimental data, as well as agreement between field data and the predictions of these models. Using the set of surviving models, we explore how changes to farming practices are predicted to influence MDV-associated condemnation risk (production losses at slaughter). By quantitatively capturing the mechanisms of disease ecology, we have laid the groundwork to explore the future trajectory of virus evolution. Keywords: Marek's disease virus, Poultry, Disease ecology, Model comparison, Plug-and-play model |
url |
http://www.sciencedirect.com/science/article/pii/S1755436517301330 |
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1725653877538160640 |