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Effects of Climate Change on Plague Exposure Pathways and Resulting Disease Dynamics

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Effects of Climate Change on Plague Exposure Pathways and Resulting Disease Dynamics Effects of Climate Change on Plague Exposure Pathways and Resulting Disease Dynamics Final Report SERDP Number 16 RC01-012 Principal Investigator: Dr. Tonie E. Rocke, U.S. Geological Survey National Wildlife Health Center Co-Investigators: Dr. Robin Russell, U.S. Geological Survey National Wildlife Health Center Dr. Michael Samuel, University of Wisconsin, Madison Co-authors: Rachel Abbott, U.S. Geological Survey National Wildlife Health Center Julia Poje, University of Wisconsin, Madison May 12, 2020 i Form Approved REPORT DOCUMENTATION PAGE OMB No. 0704-0188 The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing the burden, to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 2. REPORT TYPE 3. DATES COVERED (From - To) 05/12/2020 SERDP Final Report 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Effects of Climate Change on Plague Exposure Pathways and Resulting Disease Dynamics 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER Dr. Tonie E. Rocke, Dr. Robin Russell and Rachel Abbott RC-2634 U.S. Geological Survey National Wildlife Health Center 5e. TASK NUMBER Dr. Michael Samuel University of Wisconsin, Madison 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION U.S. Geological Survey National Wildlife Health Center REPORT NUMBER 6006 Schroeder Road 16 RC01-012 Madison, WI 53711 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR'S ACRONYM(S) Strategic Environmental Research and Development Program SERDP 4800 Mark Center Drive, Suite 17D03 Alexandria, VA 22350-3605 11. SPONSOR/MONITOR'S REPORT NUMBER(S) RC-2634 12. DISTRIBUTION/AVAILABILITY STATEMENT DISTRIBUTION STATEMENT A. Approved for public release: distribution unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT Sylvatic plague, a zoonotic flea-borne disease, caused by the bacterium Yersinia pestis, is relevant to the Department of Defense (DOD), because prairie dogs and other susceptible rodents are present on military installations in several western states. Arthropod-borne diseases, like plague, are thought to be particularly sensitive to local climate conditions. Expected changes in temperature and humidity over the next several decades will likely increase the geographical expansion of plague outbreaks in wildlife. Through a combination of field and laboratory work, along with data-driven modeling, we evaluated the potential effects of climate change on plague exposure pathways in prairie dogs and associated rodents to provide guidance to DOD partners regarding the potential for future outbreaks. Briefly, our specific objectives were to determine the relation between local climate conditions and the prevalence of plague and other pathogens while assessing the ecological roles of specific rodent hosts and vector species in plague dynamics, evaluate flea intensity on rodent hosts and in burrows in relation to local climate conditions, and develop models to predict the effects of climate change on plague dynamics. 15. SUBJECT TERMS Climate change, Cynomys spp., fleas, non-target rodents, Oropsylla spp., Peromyscus, plague, sylvatic plague vaccine, prairie dogs, Yersinia pestis 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF 18. NUMBER 19a. NAME OF RESPONSIBLE PERSON ABSTRACT OF a. REPORT b. ABSTRACT c. THIS PAGE PAGES Tonie E. Rocke 19b. TELEPHONE NUMBER (Include area code) UNCLASS UNCLASS UNCLASS UNCLASS 125 608-270-2451 Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std. Z39.18 Table of Contents List of Tables ................................................................................................................................ vi List of Figures ............................................................................... Error! Bookmark not defined. List of Appendices ........................................................................ Error! Bookmark not defined. Acronyms ...................................................................................................................................... vi Keywords ...................................................................................................................................... vi Acknowledgements ..................................................................................................................... vii Abstract .......................................................................................................................................... 8 Introduction and Objectives ..................................................................................................... 8 Technical Approach .................................................................................................................. 8 Results ........................................................................................................................................ 8 Benefits. ...................................................................................................................................... 9 Executive Summary ...................................................................................................................... 9 Introduction ............................................................................................................................... 9 Objectives ................................................................................................................................... 9 Aim 1: Ecological studies. ..................................................................................................... 9 Aim 2: Vector biology............................................................................................................ 9 Aim 3: Modeling impacts of climate change on plague dynamics. ................................... 9 Technical Approach ................................................................................................................ 10 Results and Discussion ............................................................................................................ 13 Implications for Future Research and Benefits .................................................................... 18 Final Report ................................................................................................................................. 19 Objectives ................................................................................................................................. 19 Aim 1: Ecological studies. ................................................................................................... 19 Aim 2: Vector biology.......................................................................................................... 19 Aim 3: Modeling impacts of climate change on plague dynamics. ................................. 20 Background .............................................................................................................................. 20 Materials and Methods ........................................................................................................... 21 Aim 1: Ecological studies. ................................................................................................... 21 Aim 2: Vector Biology. ........................................................................................................ 24 Aim 3: Modeling impacts of climate change on plague dynamics. ................................. 26 Results and Discussion ............................................................................................................ 29 ii Aim 1: Ecological studies. ................................................................................................... 29 Aim 2: Vector Biology. ........................................................................................................ 33 Aim 3: Modeling impacts of climate change on plague dynamics. ................................. 40 Conclusions and Implications for Future Research/Implementation ................................ 44 Literature Cited ....................................................................................................................... 46 Appendices ............................................................................................................................... 52 Appendix 1............................................................................................................................ 52 Appendix 2............................................................................................................................ 53 Appendix 3...........................................................................................................................
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