Progress 10/01/08 to 09/30/13
Outputs
Target Audience:
Nothing Reported
Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?
Nothing Reported
How have the results been disseminated to communities of interest?
Nothing Reported
What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
PI left the University of California, Davis.
Publications
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Progress 10/01/12 to 09/30/13
Outputs
Target Audience:
Nothing Reported
Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?
Nothing Reported
How have the results been disseminated to communities of interest?
Nothing Reported
What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
No funding, PD left UCD.
Publications
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Progress 10/01/11 to 09/30/12
Outputs
Target Audience:
Nothing Reported
Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?
Nothing Reported
How have the results been disseminated to communities of interest?
Nothing Reported
What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
PD left UCD. Attempts to reach him have been unsuccessful. Please remove from reporting cycle.
Publications
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Progress 01/01/11 to 09/30/11
Outputs
Target Audience:
Nothing Reported
Changes/Problems:
Nothing Reported
What opportunities for training and professional development has the project provided?
Nothing Reported
How have the results been disseminated to communities of interest?
Nothing Reported
What do you plan to do during the next reporting period to accomplish the goals?
Nothing Reported
Impacts
What was accomplished under these goals?
PI is no longer with UCD. PI assistant advises to report no activity.
Publications
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Progress 01/01/10 to 12/31/10
Outputs
OUTPUTS: Surveys were sent to over 1600 salesyard operations. After removing salesyards that are not in operation any more we obtained a data set of 1599 geocoded salesyards in the US. Out of these, 257 returned our surveys on sales practices. In addition we obtained from the internet the total sales volume in US$ for 556 salesyards. We incorporated these data into the Davis Animal Disease Simulation model (DADS model). We developed an algorithm to sample stepwise data for salesyards for which we had incomplete or no information. We compared the impact of salesyard closure on FMD in California using the DADS model. For each simulated epidemic we recorded as outcome measures the epidemic duration, the total number of infected herds, the total number of culled herds, the total number of infected animals and the total number of culled animals. The outcome measures were compared among six scenarios (three different salesyard closure strategies times two different index herds). All salesyard closure strategies closed all salesyards when the first animal was diagnosed with FMD. The first strategy kept salesyards closed throughout the entire outbreak. In the other two strategies re-opened salesyards 50 or 100 days after the onset of the epidemic. Epidemics were either started in a small (<1000 head) or a large (>1000 head) dairy herd. 300 simulations were run for each scenario. Results from this project will will written up for publication in a peer reviewed journal. Additionally the resulting improvement to the DADS model parameter values will provide stake holders with a simulation model that better reflects real world scenarios. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Our results showed generally large effects of the index herd on outbreak size but not outbreak duration. Epidemics that started in large dairy herds were approximately twice as big as epidemics that started in a small dairy herd but persisted for roughly the same duration. Re-opening salesyards had small effects on any outcome measure. These effects were not statistically detectable among the herd-level outcome measures despite the large sample size. This was true even when salesyards were re-opened after 50 days, a time when most epidemics were still active. Our results suggest that localized movement bans around known infected herds and rapid slaughter of diagnosed herds might be sufficient to bring an FMD epidemic under control. Re-opening salesyards before the end of an outbreak might be a viable option. More analysis is required to determine whether these results are robust for a range of starting conditions and model assumptions.
Publications
- No publications reported this period
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Progress 01/01/09 to 12/31/09
Outputs
OUTPUTS: Vaccination has been added to the Davis Animals Disease Simulation (DADS) model. Model users may determine the vaccination radius around diagnosed infected premises, to which species receive vaccination, time for vaccination to take effect in days, and vaccine efficacy. We chose to compare the impact of FMD vaccination for California and Indiana. The selected scenarios were as follows; 2 states (California, CA and Indiana, IN), 2 index premises types (dairy and swine) with and without vaccination for 8 total scenarios. Parameters included in the model were: 120 day cap on outbreak duration, vaccination radius 15km, vaccine only given to species of index premises type (i.e. for dairy index outbreaks, vaccination given only to dairies), time for vaccination to take effect 4 days, vaccine efficacy 80-90%. All data except for epidemic duration were transformed using square root and analyzed using ANOVA. Data were presented at the first Epidemics conference in December 2008 in Asilomar. Addition of vaccination to the simulation model allow us to now analyze various control strategies for decision makers. PARTICIPANTS: Data provided by the Indiana State Board of Animal Health. PI managed the project Analyst performed the data analysis and presented the finding at the Epidemics conference Analyst managed associated databases Analyst made necessary changes to the DADS model TARGET AUDIENCES: The research findings have been presented at academic conferences and in seminars to visiting international delegates. Carpenter, et al., "Modeling Foot-and-Mouth Disease (FMD) in the United States", Chinese Delegate Meeting, Davis, CA, March 12, 2009. Oral Presentation (R. Lopes et al.) - "Foot-and-mouth disease modeling in California: Direct and indirect contact rates among dairy herds". Epidemics conference, Asilomar, CA, Dec 1-3, 2008. Poster presentation (F. Mardones et al.) - "Duration of infectious and non-infectious periods for foot-and-mouth disease virus (FMDV) serotype O infection in cattle, pig, sheep, and goat". Epidemics conference, Asilomar, CA, Dec 1-3, 2008. Poster presentation (T. Carpenter et al.) - "A user friendly, simulation-based optimization model for epidemic disease control". Epidemics conference, Asilomar, CA, Dec 1-3, 2008. Poster presentation (C. Thunes et al.) - "A comparison of the effect of ring vaccination in controlling an outbreak of foot-and-mouth disease in California and Indiana". Epidemics conference, Asilomar, CA, Dec 1-3, 2008. PROJECT MODIFICATIONS: Not relevant to this project.
Impacts
Geographic location of an FMD outbreak as well as the type of index premises may impact the epidemic's magnitude. Decision makers therefore need a variety of control strategies that will be optimal in different situations. Vaccination was found to reduce epidemic length and total numbers of animals infected, however, constraints on vaccine availability may reduce overall effectiveness and this should be studied along with varying vaccination radii in order to ascertain the optimal strategies.
Publications
- Kobayashi M, RE Howitt, and TE Carpenter. (2009) Model could aid emergency response planning for foot-and-mouth disease outbreaks, California Agriculture, 63:137-142.
- Marshall, E.S., T.E. Carpenter, and C. Thunes. (2009). Cattle movements and other contact rates among beef herds in California, with reference to the potential spread and control of foot-and-mouth disease, JAVMA Vol. 235, No. 5, 573-579 Dickey, B.F., T.E. Carpenter and S.M. Bartell, (2008). Use of heterogeneous operation-specific contact parameters changes predictions for foot-and-mouth disease outbreaks in complex simulation models. Prev Vet Med 87, 272-287.
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Progress 01/01/08 to 12/31/08
Outputs
OUTPUTS: Duration, number of infected premises and culled animals, and spatial distribution of infected herds, resulting from the simulated outbreaks, varied considerably among geographic regions, depending on index case type and location. Outbreaks beginning in the south region of California were consistently longest, while those beginning in the north region were shortest. The largest outbreaks resulted from index cases located in the south and valley regions, while outbreaks were the smallest when originating in the Sonoma or north regions. For all regions, when the index herd was a dairy, size and duration of the outbreak were consistently reduced with implementation of a 3-day or longer SWMB. PARTICIPANTS: Nothing significant to report during this reporting period. TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.
Impacts
Results show that following the introduction of FMDV from wild pigs into a dairy or beef herd, it could result in a large and rapidly spreading outbreak, potentially affecting large numbers of herds. The size and duration of the outbreak can be reduced with an SWMB; however, the impact is highly dependent on the index herd type and location.
Publications
- Pineda-Krch, M, O'Brien, J, Thunes, C, Carpenter, TE, 2009. Potential impact of an introduction of foot-and-mouth disease from wild pigs into commercial swine and dairy premises in California, submitted to American Journal of Veterinary Research, in press.
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Progress 01/01/07 to 12/31/07
Outputs
In 2005 a paper survey of livestock producers in California was performed. Approximately 5500 surveys were mailed out with assistance from state level livestock associations, with the mean response rate of approximately 30%. In addition an online survey was released nationally in 2006 to gather similar data on a national level. In 2007 a graphic user interface (GUI) was created for the model which allows non-programmers to run scenarios for various states. Presentations made during this period are given below; Invited Presentation - (T. Carpenter ) Foreign Animal Disease Modeling, University of California, Davis; UC Davis Goat Day Meeting, January 20, 2007, 150 attendees. Organizer - (T. Carpenter ) National FMD Model Comparison Workshop: Organizer, United States Department of Agriculture, Canadian Department of Agriculture, Lawrence Livermore National Laboratory, UC Davis, Davis, CA, Participant - (T. Carpenter ) DHS Annual University Network Summit on Research and
Education: Participant, Department of Homeland Security Scientists, US University Researchers, Washington, DC, March 14 - 16, 2007, 250 attendees. Participant - (T. Carpenter) Criticality Study Workshop: Participant, DHS and National Center University Researchers, Kansas City, MO, April 3 - 4, 2007, 15 attendees. Invited Speaker (C.Thunes) - National Institute of Animal Agriculture ID Expo, Kansas City, MO, August 27 - 30, 2007, 350 - 400 attendees.
Impacts
The data collected have allowed direct and indirect parameters to be calculated for this larger geographic area and the model has been expanded to run for the state of California. Information gathered regarding movements of animals has resulted in a new shipping distance parameter. Responses are still being collected from the national survey and the model has been scaled up to run on the national level. Currently it is parameterized with the data collected in California; however, once the national data have been analyzed these will be used to make changes as necessary to model parameters. Simulation runs performed in California have looked at various scenarios including the use of alternative ring vaccination strategies, use of movement controls, the importance of knowing accurate livestock facility locations, and resource constraints for example limited amounts of vaccine. The model now runs on a 15-node computer cluster and measures were taken to increase the speed
with which simulations run. As a result the model can not only be run at the state level but also nationally. Ring vaccination and surveillance strategies, and vaccination versus depopulation strategies have been evaluated. Model output suggests that vaccination is the optimal strategy if vaccination-to-live were an option. Vaccine constraints were identified and results suggest that when vaccine is limited, for an outbreak of FMD in California, vaccine should primarily be used to vaccinate dairy animals. Model validation with UK data is currently being done.
Publications
- Marshall, E.M., Carpenter, T.E, and Thurmond, M.C. 2007. Results of a survey of owners of miniature swine to characterize husbandry practices affecting risks of foreign animal disease. JAVMA. 230, 702-707.
- Thunes, C., and Carpenter, T.E., . 2007. Biosecurity practices and travel history of individuals exhibiting livestock at the 2005 California State Fair. JAVMA. 231, 581-585.
- Carpenter,T.E, Christiansen L.E, Dickey B.F., Thunes C., and Hullinger P. 2007. The Potential Impact of an Introduction of Foot-and-Mouth Disease into the California State Fair. JAVMA. 231, 1231-1235
- Kobayashi M., B.F. Dickey, T.E. Carpenter, and R.E. Howitt. 2007. A dynamic optimal disease control model for foot-and-mouth disease. II. Model results and policy implications, Preventive Veterinary Medicine.
- Dickey, B.F., T.E. Carpenter and S.M. Bartell. 2007 Parsimony in spatial simulation modeling of livestock disease I. The role of contact parameters, Preventive Veterinary Medicine.(Submitted)
- Christiansen, L.E., and T.E. Carpenter. 2007. Comparing effectiveness of regional and circular intervention zones in case of a foot-and-mouth disease outbreak to be submitted to Preventive Veterinary Medicine or American Journal of Veterinary Research (In progress)
- Kobayashi M., B.F. Dickey, T.E. Carpenter, and R.E. Howitt. 2007. A dynamic optimal disease control model for foot-and-mouth disease. I. Model description, Preventive Veterinary Medicine.
- Christiansen, L.E., and T.E. Carpenter. 2007. An individually animal based intra-herd disease transmission model, to be submitted to Preventive Veterinary Medicine or American Journal of Veterinary Research. (In progress)
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Progress 01/01/06 to 12/31/06
Outputs
Alternative control strategies have been evaluated for application in California against FMD if it were introduced in the state. To date we have found that vaccination, if vaccinates were permitted to live, was the optimal strategy. Vaccine resource contraints have been identified.
Impacts
Identification of control strategy contraints will be identified.
Publications
- No publications reported this period
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Progress 01/01/05 to 12/31/05
Outputs
The FMD simulation model has undergone extensive revisions. Time to diagnosis of the index case has been made variable, local area spread is now encorporated in the model, regional (in addition to ring-based) controls are now permitted, and the model is currently modified to run on a computer cluster, greatly enhancing its speed. Contact data have been collected for California and they are being analyzed statistically. Results will be forthcoming.
Impacts
The spatial epidemic simulation model will be used to reduce the economic and health impact of foot-and-mouth disease if it were introduced into the United States.
Publications
- No publications reported this period
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Progress 01/01/04 to 12/31/04
Outputs
We have constructed a spatial disease simulation model that has been applied to foot-and-mouth disease (FMD) in a 3-county area in California. To date, premises have been geolocated and animal and movement patterns determined and statistically summarized. Simulation runs have been conducted to estimate the spread and control of FMD if it were to be introduced into that area. We are developing a questionnaire and geolocating additional livestock premises, throughout the state and will extend the model to that level. In the future, the model will be revised and data collected to simulate FMD spread and control on a nation wide level.
Impacts
We will have an estimate of the impact of FMD if it were introduced into the US. The impact will include animal numbers, by species and production type, that may be slaughtered or vaccinated. In addition, we will identify economically optimal ways of controlling or eradicating FMD if it were to enter the US.
Publications
- Carpenter TE, MC Thurmond and TW Bates. 2004. A simulation model of intra-herd transmission of foot and mouth disease virus with reference to disease spread before and after clinical diagnosis. J. Vet. Diagn. Inv. 16:10-15.
- Bates TW, MC Thurmond and TE Carpenter. 2003. Description of an epidemic simulation model for use in evaluating strategies to control an outbreak of foot-and-mouth disease. A.J.V.R. 64:195-204.
- Bates TW, MC Thurmond and TE Carpenter. 2003. Results of an epidemic simulation model to evaluate strategies to control an outbreak of foot-and-mouth disease. A.J.V.R. 64:205-210.
- Bates TW, TE Carpenter and MC Thurmond. 2003. Benefit-cost analysis of vaccination and preemptive slaughter as means of eradicating foot-and-mouth disease. A.J.V.R. 64:805-812.
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