Knowledge and Perception of Lyme Disease in Manitoba: Implications for Risk Assessment by Kathleen Crang A Thesis submitted to the Faculty of Graduate Studies of The University of Manitoba in partial fulfilment of the requirements of the degree of MASTER OF ENVIRONMENT Department of Environment and Geography University of Manitoba Winnipeg Copyright @ 2009 by Kathleen Crang THB UNIVBRSITY OF MANITOBA FACULTY OF GRADT]ATE STUDIBS COPYRIGHT PBRMISSION Knowledge and Perception of Lyme Disease in Manitoba: lmplications for Risk Assessment By Kathleen Crang A Thesis/PI'acticum submitted to the Faculty of Gracluatc Stutlies of Thc Uniyersitv of Manitob¿r in ¡rartial fulfillrnent of the req uire ment of the degrce of Master of Environment Kathleen CrangO2009 Permission has been grantecl to the Universit),of Manitob¿r Libraries to lcnd a copy of this thesis/practicum, to Library and Archives Canatla (LAC) to lencl ¿r cop)¡ of this thesis/¡lr.acticum, arltl to LAC's agent (UMI/ProQuest) to microfilm, sellcopies and to publish an ¿rbstract of this thesis/¡r racticu rn. This reproduction or copy of this thesis has been rn¿rde available by ¿ruthority of the copyright olner solely for the purpose of private study ancl research, ancl may onl5, 5" reir.oducerl ana copiea :rs permittecl by copyright lan's or lvith express rvritten authorization from the copyright on,ner. Table of Contents Abstract.... iv Acknowledgements.... .......... v List of Tab1es............. .... vi List of Figures............. .......... vii Permission List for Copyrighted Material ....... viii Chapter I: Introduction............. I Literature Review. 2 Research Objectives and Questions... ..... 11 Chapter II: Research Methods ..... 13 Chapter III: Ecology and Epidemiology of Lyme Disease. .. 30 The Lyme Disease Pathogens: Borcelia burgdorferi sensu lato. .. ... 30 Lyme Disease Vectors. .... 4I IxodesVectors. ........59 Possible Tick Vectors other than lxodes . .. ... 7 | Dermacentor species. ....... 74 Tick Vector Life Cycles and Competence. ...... 79 Possible Non-tick Arthropod Vectors. 87 Mechanical Vector Transmission of LD. ......... 91 Lyme Disease Hosts and Reservoirs... .......... 93 Small Mammal Hosts and Reservoirs... ... 95 Large Mammal Hosts. I02 Other Lyme Disease Risk Factors..... I 10 Lyme Disease Symptoms and Diagnosis.............. 116 Chapter IV: Spatial Distribution of Lyme Disease. A Case for Manitoba.. ... I27 Global and European Patterns I28 North American Patterns..... 131 Patterns in Canada and Manitoba.... 135 Lyme Disease Mimicry. 140 Multiple Sclerosis. .... 144 Lupus. .........152 Arthritis. ...... 153 Fibromyalgia..... ..... 153 Crohn's Disease. .... I54 Other Diseases. ....... 155 Chapter V: Risk Perception of Lyme Disease in Manitoba...... 157 Chapter VI: Conclusions . 198 Further Research and Policy Implications ..... ..... 205 Glossary of Terms. .... 209 References .. 212 111 Abstract Understanding the epidemiology and nature of Lyme disease (LD) in Manitoba, and the perception of its risk to the population of the province are important for the development of appropriate provincial public health policies, for guiding clinicians in their practices, and for general public awareness to minimize risk to the population. However, there is minimal research into knowledge levels and resulting perceptions of Lyme disease, and how those perceptions influence various groups in their practices. The objective of this study was to explore four groups for their knowledge level and perceptions of Lyme disease: scientists, policy/decision makers, clinicians, and disease-specific advocates. A grounded theory approach was used as the research framework. Semi-structured interviews were completed with a sample of 23 key informants from the four groups. One major category: knowledge and understanding of LD, and 5 sub-categories emerged from the data. These were: lack of knowledge and understanding of LD, application of LD knowledge, LD transmission, individual roles, and personal perspectives. The findings indicate the importance of the critical current science of Lyme disease being disseminated across the four groups, to enable the development of risk perceptions conducive to effective disease control. Identification of barriers in communication between the groups can be used to develop strategies to facilitate further research, public health, and public education in the province. 1V Acknowledgements The writer wishes to acknowledge and thank advisor Dr. Paul Hackett for his long-term support and extensive expertise, along with committee members Dr. Borurie Hallman and Dr. Lawrence Elliott for their time and expert contributions to this thesis. List of Tables Table 1. Codes and Abbreviations used in transcript analysis. 22 Table 2. Borcelia burgdorferi sensu lato genospecies and their distribution (asof2002)... .. 32 Table 3. Tick Classif,rcation.... 42 Table 4. Manitoba Tick Sightings 1988 to 1998.. 6l Table 5. Ticks collected in Saskatchewan during a passive surveillance progtam conducted in 1998. 77 Table 6. Incidence of Lyme disease in European Countries. 129 Table 7. Original Diagnosis of Patients testing positive for Borrelia burgdorferi.. t43 vl List of Figures Figure 1. Code Category Map.. 23 Figure 2. Step Model of Inductive Category Development.. 26 Figure 3. Ixodid Life Cycle. .......... 43 Figure 4. Distribution of lxodes ticks in Europe and Asia. 46 Figure 5. U.S. Range of I. scapularis andI. pacificus ......... 46 Figure 6. The distribution of lxodes scapularis reflecting information submitted to provincial and federal public health agencies from January 1990 to December 2003 and to the Lyme Disease Associationof Ontario for 1993 to 1999. .......... 47 Figure 7. Public Advertisement: You Can Help in the Study of Lyme Disease.. .. 60 Figure 8. Density of white-footed mice in North America. .... 97 Figure 9. Range of White-tailed Deer in Manitoba...... ........ 105 Figure 10. Reported Number of Lyme Disease Cases by State, United States 1996J32 Figure i1. Reported Cases of Lyme Disease inthe U.S. 1986 - 1996. ...... 133 Figure 12. Reported Cases of Lyme Disease by Year, United States, 1994-2008.. 133 Figure 13. Annual number of cases of Lyme disease cases reported voluntarily by the provinces and territories since the late 1980s. ........ 135 Figure 14. Schizophrenia and Lyme disease in the United States. ... 155 vll Permission List for Copyrighted Material Figure 6. The distribution of lxodes scapularís reflecting information submitted to provincial and federal public health agencies from January 1990 to December 2003 and to the Lyme Disease Association of Ontario for 1993 to 1999 - - reprinted from the Canadian Medical Association Journal (CMAJ) June 2009; (Issue 12), (Volume 180), p.1223 bypermissionofthepublisher. @2009 Canadia¡rMedicalAssociation...... 47 Figure 13. Annual number of cases of Lyme disease cases reported voluntarily by the provinces and territories since the late 1980s - reprinted from the Canadian Medical Association Journal (CMAJ) June 2009; (Issue 12), (Volume 180), p. 1223 by permission of the publisher. @ 2009 Canadian Medical Association 135 vl1t Chapter I: Introduction This thesis seeks to examine the current understanding of the epidemiology of Lyme disease, the nature of the disease in Manitoba, and the perception of its risk to the population of the province. Lyme disease (LD), or Lyme borreliosis is a zoonotic infectious disease resulting from a bacterial Borcelia infection maintained in a variety of animal hosts and reservoirs, and thought to be vectored primarily by certain lxodes tick species . Zoonotic infectious diseases in general exist within a host and parasite continuum between wildlife, domestic animal and human populations (Artsob, I997;Daszak, Cunningham and Hyatt, 2000). Serious systemic health impacts result from Lyme disease, and Aultman, Walker, Gifford, Beard, Scott and Severson (2000) include this disease with other worldwide arthropod-borne pathogens such as malaria and African sleeping sickness that continue to pose enonnous health threats. For infectious diseases like LD with fairly high global incidence, studying the epidemiology and ecology of the disease is important, since there are important regional variations in the disease cycle (Pleasant, 2000). Lyme disease is noted for its wide geographical distribution in the northern hemisphere (Gray, Kahl, Lane and Stanek, 2002), yet there are few reported cases of Lyme disease in Manitoba and throughout Canada, compared to other northem countries where fhe Borrelia pathogen is ecologically successful. The understanding of the disease, and perception of LD risk in Manitoba are important for the development of appropriate provincial public health policies, for guiding clinicians in their practices, and for general public awareness to minimize risk to the population. Literature Review The general th¡ead through the literature indicates that a lack of knowledge and understanding of Lyme disease, and difficulties associated with risk assessment might influence the perception of risk held by individuals and various goups. Lyme disease is documented as one of the most controversial illnesses in the history of medicine (Johnson and Stricker,2009). "Lyme disease is a growing public health threat" (Stricker, Lautin and Burrascano, 2006), yet the slim Manitoba literature indicates the risk is low, and could be influencing the perception of risk in the province. A health risk is defined as a chance of receiving a negative impact to health, as a result