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Development of a Novel Rabies Simulation Model for Application in a Non-endemic Environment.

Dürr S, Ward MP - PLoS Negl Trop Dis (2015)

Bottom Line: Mathematical and simulation disease models are useful tools to provide insights on the most effective control strategies and to inform policy decisions.Illustrative simulations produced plausible results with epidemic characteristics expected for rabies outbreaks in disease free regions (mean R0 1.7, epidemic peak 97 days post-incursion, vaccination as the most effective response strategy).Systematic sensitivity analysis identified that model outcomes were most sensitive to seven of the 30 model parameters tested.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Veterinary Science, The University of Sydney, Camden, New South Wales, Australia.

ABSTRACT
Domestic dog rabies is an endemic disease in large parts of the developing world and also epidemic in previously free regions. For example, it continues to spread in eastern Indonesia and currently threatens adjacent rabies-free regions with high densities of free-roaming dogs, including remote northern Australia. Mathematical and simulation disease models are useful tools to provide insights on the most effective control strategies and to inform policy decisions. Existing rabies models typically focus on long-term control programs in endemic countries. However, simulation models describing the dog rabies incursion scenario in regions where rabies is still exotic are lacking. We here describe such a stochastic, spatially explicit rabies simulation model that is based on individual dog information collected in two remote regions in northern Australia. Illustrative simulations produced plausible results with epidemic characteristics expected for rabies outbreaks in disease free regions (mean R0 1.7, epidemic peak 97 days post-incursion, vaccination as the most effective response strategy). Systematic sensitivity analysis identified that model outcomes were most sensitive to seven of the 30 model parameters tested. This model is suitable for exploring rabies spread and control before an incursion in populations of largely free-roaming dogs that live close together with their owners. It can be used for ad-hoc contingency or response planning prior to and shortly after incursion of dog rabies in previously free regions. One challenge that remains is model parameterisation, particularly how dogs' roaming and contacts and biting behaviours change following a rabies incursion in a previously rabies free population.

No MeSH data available.


Related in: MedlinePlus

Daily model simulation actions in chronological order.On the right side of the figure the parameters used for each action are presented. For the update of the disease states each rabies exposed (E) dog develops subclinical rabies (SC), clinical rabies (C) and finally dies because of rabies or culling (D). At the end of each day, the model checks whether the criteria to stop the simulation are met or whether the loop will be repeated the next day. Dog confinement strategy and between-community movement ban are timely applied during the between-household and between-community contacts, respectively.
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pntd.0003876.g001: Daily model simulation actions in chronological order.On the right side of the figure the parameters used for each action are presented. For the update of the disease states each rabies exposed (E) dog develops subclinical rabies (SC), clinical rabies (C) and finally dies because of rabies or culling (D). At the end of each day, the model checks whether the criteria to stop the simulation are met or whether the loop will be repeated the next day. Dog confinement strategy and between-community movement ban are timely applied during the between-household and between-community contacts, respectively.

Mentions: At the start of the simulation a user defined number of index dogs is chosen randomly, or alternatively a specific dog can be defined as the index dog (to test different control strategies assuming identical starting conditions). Every simulated day, the model chronologically loops through simulation actions (Fig 1) and ends when either the user defined maximum time has been reached (irrespective of whether the outbreak has ended) or when no (latently) infected dog remains.


Development of a Novel Rabies Simulation Model for Application in a Non-endemic Environment.

Dürr S, Ward MP - PLoS Negl Trop Dis (2015)

Daily model simulation actions in chronological order.On the right side of the figure the parameters used for each action are presented. For the update of the disease states each rabies exposed (E) dog develops subclinical rabies (SC), clinical rabies (C) and finally dies because of rabies or culling (D). At the end of each day, the model checks whether the criteria to stop the simulation are met or whether the loop will be repeated the next day. Dog confinement strategy and between-community movement ban are timely applied during the between-household and between-community contacts, respectively.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4482682&req=5

pntd.0003876.g001: Daily model simulation actions in chronological order.On the right side of the figure the parameters used for each action are presented. For the update of the disease states each rabies exposed (E) dog develops subclinical rabies (SC), clinical rabies (C) and finally dies because of rabies or culling (D). At the end of each day, the model checks whether the criteria to stop the simulation are met or whether the loop will be repeated the next day. Dog confinement strategy and between-community movement ban are timely applied during the between-household and between-community contacts, respectively.
Mentions: At the start of the simulation a user defined number of index dogs is chosen randomly, or alternatively a specific dog can be defined as the index dog (to test different control strategies assuming identical starting conditions). Every simulated day, the model chronologically loops through simulation actions (Fig 1) and ends when either the user defined maximum time has been reached (irrespective of whether the outbreak has ended) or when no (latently) infected dog remains.

Bottom Line: Mathematical and simulation disease models are useful tools to provide insights on the most effective control strategies and to inform policy decisions.Illustrative simulations produced plausible results with epidemic characteristics expected for rabies outbreaks in disease free regions (mean R0 1.7, epidemic peak 97 days post-incursion, vaccination as the most effective response strategy).Systematic sensitivity analysis identified that model outcomes were most sensitive to seven of the 30 model parameters tested.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Veterinary Science, The University of Sydney, Camden, New South Wales, Australia.

ABSTRACT
Domestic dog rabies is an endemic disease in large parts of the developing world and also epidemic in previously free regions. For example, it continues to spread in eastern Indonesia and currently threatens adjacent rabies-free regions with high densities of free-roaming dogs, including remote northern Australia. Mathematical and simulation disease models are useful tools to provide insights on the most effective control strategies and to inform policy decisions. Existing rabies models typically focus on long-term control programs in endemic countries. However, simulation models describing the dog rabies incursion scenario in regions where rabies is still exotic are lacking. We here describe such a stochastic, spatially explicit rabies simulation model that is based on individual dog information collected in two remote regions in northern Australia. Illustrative simulations produced plausible results with epidemic characteristics expected for rabies outbreaks in disease free regions (mean R0 1.7, epidemic peak 97 days post-incursion, vaccination as the most effective response strategy). Systematic sensitivity analysis identified that model outcomes were most sensitive to seven of the 30 model parameters tested. This model is suitable for exploring rabies spread and control before an incursion in populations of largely free-roaming dogs that live close together with their owners. It can be used for ad-hoc contingency or response planning prior to and shortly after incursion of dog rabies in previously free regions. One challenge that remains is model parameterisation, particularly how dogs' roaming and contacts and biting behaviours change following a rabies incursion in a previously rabies free population.

No MeSH data available.


Related in: MedlinePlus