Distributional Studies of Parasitic Arthropods in Utah Determined As Actual and Potential Vectors of Rocky Mountain Spotted Feve
Total Page：16
File Type：pdf, Size：1020Kb
Brigham Young University Science Bulletin, Biological Series Volume 1 Number 1 Article 1 3-1-1955 Distributional studies of parasitic arthropods in Utah determined as actual and potential vectors of Rocky Mountain spotted fever and plague: with notes on vector-host relationships D Elden Beck Department of Zoology and Entomology, Brigham Young University Follow this and additional works at: https://scholarsarchive.byu.edu/byuscib Part of the Anatomy Commons, Botany Commons, Physiology Commons, and the Zoology Commons Recommended Citation Beck, D Elden (1955) "Distributional studies of parasitic arthropods in Utah determined as actual and potential vectors of Rocky Mountain spotted fever and plague: with notes on vector-host relationships," Brigham Young University Science Bulletin, Biological Series: Vol. 1 : No. 1 , Article 1. Available at: https://scholarsarchive.byu.edu/byuscib/vol1/iss1/1 This Article is brought to you for free and open access by the Western North American Naturalist Publications at BYU ScholarsArchive. It has been accepted for inclusion in Brigham Young University Science Bulletin, Biological Series by an authorized editor of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. S-/f/fi p£'zl BrighamBri Young University Science Bulletin *'^s co^^ BIOLOGICAL SERIES — VOLUME I, NUMBER "y^^f^s/-^ March h 1955 DISTRIBUTIONAL STUDIES OF PARASITIC ARTHROPODS IN UTAH, DETERMINED AS ACTUAL AND POTENTIAL VECTORS OF ROCKY MOUNTAIN SPOTTED FEVER AND PLAGUE, with notes on VECTOR-HOST RELATIONSHIPS by D ELDEN BECK Published by BRIGHAM YOUNG UNIVERSITY Provo, Utah Brigham Young University Science Bulletin BIOLOGICAL SERIES — VOLUME I, NUMBER I March J, 7955 DISTRIBUTIONAL STUDIES OF PARASITIC ARTHROPODS IN UTAH, DETERMINED AS ACTUAL AND POTENTIAL VECTORS OF ROCKY MOUNTAIN SPOTTED FEVER AND PLAGUE, with notes on VECTOR-HOST RELATIONSHIPS by D ELDEN BECK Published by BRIGHAM YOUNG UNIVERSITY Prove, Utah TABLE OF CONTENTS Introduction 1 Objectives 1 Survey procedure - 1 Host collections 2 Consortes collections 2 Problems of survey related to geography 2 Biotic communities 7 Acknowledgments - 10 Part I Plague Vector Investigations 15 Introduction 15 Discussion of the disease 15 Etiology - 15 Host relationship 15 Historical resume 16 Early history _ 16 Plague in western U. S _ 17 Plague in Utah _ 17 Plague and endemicity _ 18 Plague and plague vectors _ 19 Seasonal variations in vector populations _ 22 Reservoir hosts and plague vectors _ 22 Reservoir hosts of plague in Utah _ 22 Fleas as plague vectors in Utah _ 24 Fleas and murine plague in Utah _ 24 Capable vectors _ 25 Potential vectors _ 32 Summary and conclusions 35 Literature cited 35 Part II Rocky Mountain Spotted Fever Vector Investigations 38 Introduction 38 Etiological agent . 44 Distribution of the disease and case fatality 44 In the United States 44 In Utah 45 Host relationship and the disease 45 Vector and disease relationship in North America 46 Vector and disease relationship in Utah 47 Life history and seasonal variation 47 Dennacentor andersoni 47 D. parumapertus 50 Haemaphysalis leporis - palustris 52 Vector host association and distribution 52 D. andersoni 52 D. parumapertus 54 D. albipictns _ 54 H. leporis - palustris _ 54 Ornithodoros parkeri _ 54 Summary and conclusions 60 Literature cited 61 LIST OF ILLUSTRATIONS INTRODUCTION Page Figure 1. Principal physiographic areas of Utah 3 Figure 2. Great Basin and Colorado River Basin regions in Utah 4 Figure 3. Great Basin and Colorado River Basin regions in Utah with reference to the political subdivisions 5 Figure 4. Physiographic map of Utah on which are listed the principal biotic communities, the primary physiographic regions as well as drainage basins 6 Figure 5. Desert island mountains created by intrusive uptbrusts in Grand and San Juan Counties 8 Figure 6. Southern Desert Shrub Community 9 Figure 7. Shallow, desert drainage basin near Green River, Emery County 9 Figure 8. Farming village of Fruita in Capitol Reef National Monument, Wayne County 11 Figure 9. Great Basin desert flatland as seen at the Desert Range Experiment Station in western Millard County 11 Figure 10. Juniper woodland about 3 miles north of Jericho, Juab County, on U.S. Highway 6 12 Figure 11. Transition Zone as found on the Wasatch Range in Provo Canyon of Utah County .. 13 Figure 12. Boreal environment near timberline in the La Sal mountains area of Grand and San Juan Counties 13 PART I Table 1. Vector-host relationship in Utah collections for vectors of plague listed as capable vectors 20-21 Table 2. Vector-host relationship for vectors of plague in Utah listed as potential vectors 26-27 Table 3. Distributional pattern by counties in Utah for fleas implicated as capable vectors of plague - 28 Table 4. Distributional pattern by counties in Utah for fleas implicated as potential vectors of plague 29 Table 5. Distribution by County of potential and capable plague vectors with reference to hosts which have been shown to be plague implicated 30-31 Figure 13. Distributional pattern for those species of fleas in Utah listed as the effective capable vectors for plague 33 Figure 14. Map showing the general distributional pattern for fleas listed as capable vectors for plague 34 PART II Table 1. Rocky Mountain spotted fever cases in Utah 40 Table 2. Rocky Mountain spotted fever cases in Utah from 1924 to 1932 41 Table 3. Rocky Mountain spotted fever cases in Utah from 1933-1942 42 Table 4. Rocky Mountain spotted fever cases in Utah. Case totals and fatality rates for State and Counties from 1915 to 1942 43 Table 5. Vector-host relationships for D. andersoni and D. parumapertus with reference to collections made at low and high altitudes 55 Table 6. Distribution by county of capable and potential vectors of Rocky Mountain spotted fever in Utah 56 Figure 1. Seasonal population variations 48 Figure 2. Collection records for larvae and nymphs of D. pannnapertus from specific hosts .. 48 Figure 3. Seasonal population variations for adult, larval, and nymphal ticks of Haemaphysalis leporis-jmliisti-is 49 Figure 4. Seasonal population variations for larval and nymphal ticks of Dermacentor andersoni collected at high altitudes 49 Figure 5. Comparative numbers of larval and nymphal tick collections of Dermacentor sp. .. 51 Figure 6. Seasonal population variation of larvae and nymphs at Lucin and Cedar Valley in the Great Basin region in Utah 56 Figure 7. Distributional pattern for collections of Dermacentor andersoni in Utah 57 Figure 8. Distributional pattern for collections of Dermacentor parumapertus in Utah 58 Figure 9. Distributional pattern for collections of Haemaphysalis lepoi-is-palustris in Utah .... 59 U . DISTRIBUTIONAL STUDIES OF PARASITIC ARTHROPODS IN UTAH, DETERMINED AS ACTUAL AND POTENTIAL VECTORS OF ROCKY MOUNTAIN SPO'lTED FEVER AND PLAGUE, WITH NOTES ON VECTOR-HOST RELATIONSHIPS by D Elden Beck Department of Zoology and Entomology INTRODUCTION Preliminary investigations were s1 ;rted on grazing domains, wilderness areas and mining this project in the spring of 1948. The Division locations in both desert and mountainous situ- of Research Grants and Fellowships of the ations were surveyed. Since the hinterland National Institutes of Health, Department of areas in the southeastern section of Utah are Health, Education, and Welfare, U. S. Public being invaded by many hundreds of uranium Health Service, established a research grant for prospectors, it was felt that significant surveys this study at the Brigham Young University in this extensive area would be of value from a September 1, 1950. The author, a member of public health point of view. Sui"veys were also the faculty of the Department of Zoology and made in some of the national parks and monu- Entomology at the grantee institution, was ments within the S'.ate of Utah, visited annually named the principal investigator. The project by many thous-^'s of tourists. Finally, spot was designed for a three year period of study. checking was done along the principal arterial Most of the work originally planned has now state and federal highways in Utah. been completed and is being reported upon in Field surveys were conducted on a year- this paper. round basis, insofar as host animals were avail- able and access to areas was possible. Hosts were Objectives of the study were as follows: captured both alive and dead, by whatever 1 To locate and identify the species of known means best suited the conditions of collecting, vectors of plague and Rocky Mountain spot- Several types of live traps were utilized. Some ted fever in Utah. types of live traps were more effective in trap- ping certain animals than others, and certain 2. To specifically identify hosts with which traps were effective others differ- the known vectors would be associated and more than in ent kinds of habitats different show their geographic distribution. and at seasons. Dead hosts were usually captured by snap traps 3. To determine and locate in Utah the known or by shooting with the appropriate calibre or reservoir hosts for plague and Rocky Moun- gauge of gun. tain spotted fever. 4. To make observations on vector-host re- If an animal were captured alive, it was lationships. then taken to the field station or laboratory 5. To record, insofar as possible, information where it was chloroformed and the body care- on vector populations in order to determine fully examined for parasites. Dead animals seasonal variations if any. were placed directly from the trap into paper bags and then taken to the field station or lab- 6. To conduct investigations both in the field oratory where the body was subjected to the and by laboratory studies which would help chloroform treatment which drove the para- solve some problems related to life histories sites from the host or made it possible for the of various species involved as vectors of parasites to be brushed or otherwise removed Rocky Mountain spotted fever and plague.