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Characterization of Rickettsial Infection Dynamics Within Dermacentor Louisiana State University LSU Digital Commons LSU Doctoral Dissertations Graduate School 2016 Characterization of rickettsial infection dynamics within Dermacentor variabilis and Amblyomma maculatum Emma Kate Harris Louisiana State University and Agricultural and Mechanical College, [email protected] Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_dissertations Part of the Veterinary Pathology and Pathobiology Commons Recommended Citation Harris, Emma Kate, "Characterization of rickettsial infection dynamics within Dermacentor variabilis and Amblyomma maculatum" (2016). LSU Doctoral Dissertations. 1426. https://digitalcommons.lsu.edu/gradschool_dissertations/1426 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Doctoral Dissertations by an authorized graduate school editor of LSU Digital Commons. For more information, please [email protected]. CHARACTERIZATION OF RICKETTSIAL INFECTION DYNAMICS WTIHIN DERMACENTOR VARIABILIS AND AMBLYOMMA MACULATUM A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Doctor of Philosophy in The Interdepartmental Program in Biomedical and Veterinary Medical Sciences Through the Department of Pathobiological Sciences by Emma Kate Harris A.A., Pearl River Community College, 2007 B.S., Mississippi University for Women, 2010 August 2016 ACKNOWLEDGMENTS Not a single moment of my very fortunate life has been possible without the love and support of so many people who taught me what it really means to possess intelligence. I would like to thank my grandfather, my Daddy Fritz. If he had never taken his first bus, which took him to his first train, to meet his first taxi, allowing him to attend college for the first time, I would have never been inspired to achieve something that seemed so far out my own reach. To my Dot- Dot, your kind and steady hand has guided me the whole way through. Don’t worry I’ll be home to visit very soon and I’m looking forward to a cup of coffee. To my Granny, the toughest person I’ve ever met, thank you for being a shining example of hard work and perseverance. I would like to thank my parents Paul and Deborah for their unconditional love and support. You’ve taught me to be a person of integrity, something I hope I always remember. My siblings, Dana, Hannah, Jill, and Michael, you continually push me to better at everything I do and I’m so lucky to have you. I would like to thank everyone in the PBS department for their smiles and kindness. I am thankful to all the members of the Macaluso laboratory: Dr. Piyanate Sunyakumthorn, Dr. Britt Grasperge, Dr. Natthida Petchampai, Dr. Chanida Fongsaran, Dr. Rebekah Bullard, Krit Jirakanwisal, Sean Healy, Nam Suwanbongkot, Kelsey Legendre, Wellesley Ditmar, Nicole Carrasquillo-Coto, Grady Baylin, Melena Hagstrom, and Allison Latour. You have all taught me skills and techniques with patience and adeptness. I am truly in your debt. Dr. Victoria Verhoeve, we began as frenemies and somehow you became that fourth sister that aggravated me even more than my actual ones. Thanks, gal! Dr. Lisa Brown, I still look for you to be across the bench from me ready to share in gossip or just to tease Khush. Thank you Dr. Khush (B.) Banajee, for your patience and, quite often, your looks of doubt. ii To the members of the Simoes laboratory, I feel so European thanks to you. Dr. Isaura Simoes, I hope to one day be half the researcher, person, and friend that you are. You have taught me that kindness and science exist. The many times I was weary of working, you reminded me I could do this. Pedro Curto, what can I say? You have laughed at me so much that even I began to laugh, an invaluable tool for me. To the Martinez laboratory, thank you for the swift kick in the pants. Abbie Fish and Daniel Garza, you will never know how much you motivated me to keep pushing forward. You are always a kind ear to listen at the many times when I needed it. Danny, thanks for being my running buddy, even at six in the morning. Dr. Sean Riley, you have been so patient and understanding. There is no way I would have been able to finish this dissertation document with you! Your guidance was invaluable at a time when I truly need it. I am forever indebted to you. I would also like to thank my graduate committee, Dr. Hawke, Dr. Foil, and Dr. Yoshimura for their wonderful guidance. Lastly, I would like to thank my mentor Dr. Macaluso. I choose to believe that you knew what you were getting yourself into six years ago. Surely, if you did not then you do now. I am ever grateful for your attention and patience in teaching me to be a scientist of depth and thoroughness. iii “The Building of the Ship” “Like unto ships far off at sea, Outward or homeward bound, are we. Before, behind and all around, Floats and swings the horizon’s bound, Seems at its distant rim to rise And climb the crystal wall of the skies, And then again to turn and sink, As if we could slide from its outer brink. Ah! It is not the sea, It is no the sea that sinks and shelves, But ourselves That rock and rise With endless and uneasy motion, Now touching the very skies, Now sinking into the depths of the ocean. Ah! If our souls but poise and swing Like the compass in its brazen ring, Ever level and ever true To the tail and the task we have to do, We shall sail securely, and safely reach The Fortunate Isles, on whose shining beach The sights we see, and the sounds we hear, Will to those of joy and not of fear!” -Henry Wadsworth Longfellow iv TABLE OF CONTENTS ACKNOWLEDGMENTS .............................................................................................................. ii LIST OF TABLES ....................................................................................................................... viii LIST OF FIGURES ....................................................................................................................... ix ABSTRACT ................................................................................................................................... xi CHAPTER 1 INTRODUCTION AND LITERATURE REVIEW ................................................ 1 1.1 Ticks: Arthropods of Importance and Variety .......................................................................... 1 1.1.1 Life History and Description: Ixodidae, Argasidae, and Nuttalliellidae ........................ 1 1.1.1a Anatomy of the Ixodid tick ...................................................................................... 1 1.1.1b Ixodidae.................................................................................................................... 3 1.1.1c Argasidae.................................................................................................................. 7 1.1.1d Nuttalliellidae ........................................................................................................... 8 1.1.1e Bloodmeal Digestion ................................................................................................ 9 1.1.1f Host-Finding Strategies .......................................................................................... 10 1.1.2 Ticks as Vectors of Diseasing Causing Agents ............................................................ 11 1.1.3 Amblyomma maculatum Life History ........................................................................... 11 1.1.3a Biology ................................................................................................................... 13 1.1.3b Veterinary and Medical Importance ...................................................................... 14 1.1.4 Dermacentor variabilis Life History ............................................................................ 15 1.1.4a Biology ................................................................................................................... 16 1.1.4b Medical and Veterinary Importance ...................................................................... 17 1.2 The Genus Rickettsia .............................................................................................................. 17 1.2.1 General information .................................................................................................... 17 1.2.2 Historical Perspective ................................................................................................. 22 1.2.3 SFG Rickettsia Disease Etiology ................................................................................ 23 1.3 The Tick/Rickettsia Relationship ............................................................................................ 25 1.3.1 Vector Competence ..................................................................................................... 25 1.3.1 Rickettsia rickettsii ...................................................................................................... 27 1.3.2 Rickettsia parkeri ........................................................................................................ 28 1.3.3 Rickettsia amblyommii ................................................................................................ 29 1.3.4 Rickettsia montanensis ................................................................................................ 30 1.4 Rickettsial Factors Associated with Infection
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