DOCSLIB.ORG

NOVEL MOLECULAR STRATEGIES for the DETECTION and CHARACTERIZATION of TICK-BORNE PATHOGENS in DOMESTIC DOGS a Dissertation By

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
NOVEL MOLECULAR STRATEGIES for the DETECTION and CHARACTERIZATION of TICK-BORNE PATHOGENS in DOMESTIC DOGS a Dissertation By NOVEL MOLECULAR STRATEGIES FOR THE DETECTION AND CHARACTERIZATION OF TICK-BORNE PATHOGENS IN DOMESTIC DOGS A Dissertation by JOSEPH JAMES MODARELLI II Submitted to the Office of Graduate and Professional Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Chair of Committee, Maria D. Esteve-Gasent Co-Chair of Committee, James N. Derr Committee Members, Pamela J. Ferro John M. Tomeček Head of Department, David Threadgill December 2018 Major Subject: Genetics Copyright 2018 Joseph James Modarelli II ABSTRACT Tick-borne diseases (TBD) are common across the United States and can result in critical and chronic disease states in a variety of veterinary patients, specifically domesticated dogs. Borreliosis, anaplasmosis, rickettsiosis, ehrlichiosis, and babesiosis have been cited as the most common TBDs. Despite recent reports revealing past exposure of TBD, there are no molecular epidemiological reports for dogs in Texas. Therefore, data to support the level of actively infected dogs in the population is inadequate. Limited molecular data for TBDs is due, in part, to the lack of consolidated molecular tools available to researchers. Real-time PCR (qPCR) assays are a commonly utilized tool for molecular detection of TBDs, and achieve species specificity by assigning each pathogen a unique fluorogenic label. However, current limitations of qPCR instruments include restricting the number of fluorogenic labels that can be differentiated by the instrument per a given reaction. As such, this dissertation explored the development of a qPCR methodology, termed layerplexing, that would allow for the simultaneous detection and characterization of 11 pathogens responsible for causing common TBDs in domestic dogs. Additionally, an endogenous internal positive control was designed and integrated into the assay for quality assurance of attained molecular results. Analysis revealed that the layerplex assay format was comparable in terms of target sensitivity and specificity to other qPCR assays utilized in the field. The layerplex assay was then applied to conducting a molecular prevalence investigation of TBDs affecting dogs across Texas ecoregions. By conducting molecular prevalence studies for TBDs, updated rates of active exposure and specific regions that may contain sentinels of disease could be identified. Results obtained ii indicated molecular prevalence of borrelial, rickettsial, and babesial pathogens varied across the Texas study area and indicated specific regions where susceptible hosts may be at higher risk for infection with TBD. Furthermore, the layerplex assay lead to the first reported molecular detection of Anaplasma platys in Texas and coinfection with Ehrlichia canis and A. platys in Texas dogs. Overall, findings from this dissertation provided substantial evidence that the layerplex technique can be utilized for grouping multiple targets under a single fluorogenic label without impeding diagnostic efficacy. The layerplex technique also demonstrated utility in facilitating large scale molecular analyses of animals in Texas. Surveillance data obtained from this study may aid public health agencies in updating maps depicting high-risk areas of disease and provide baseline data for future research aiming to characterize TBDs in additional animal models. iii DEDICATION To my family, for always supporting my endeavors. To my friends, for humoring my passions. To the Interdisciplinary Graduate Program in Genetics, College of Veterinary Medicine, and the TVMDL, for providing me the opportunity to apply my research to the field of diagnostics. Most of all, to my wife, Rachel, who has never stopped encouraging or inspiring me. iv ACKNOWLEDGEMENTS I would like to thank my committee chair Dr. Esteve-Gasent for all her patience, guidance, and support; my co-chair Dr. Derr for introducing me to the field of genetics; and my committee members, Dr. Ferro for teaching me how to apply a pursuit in genetics to the field of veterinary diagnostics, Dr. Tomeček for introducing me to the importance of wildlife surveillance, and Dr. Walt Cook for his willingness to assist in my defense. Special thanks to the TVMDL for providing me the opportunity to pursue a graduate degree and equipping me with a wealth of knowledge from on-site subject matter experts. I want to extend additional thanks to Dr. Ferro for not only supporting my desire to pursue a career in research, but also for pushing me out of my comfort zone so that I can attain the full graduate student experience. Special thanks to Interdisciplinary Graduate Program in Genetics Chair Dr. Threadgill, Veterinary Pathobiology Department Head Dr. Vemulapalli, as well as the faculty and staff of the departments for their support. Thanks also to our laboratory’s former students Dr. Christina Brock and Dr. Amer Fadhl Alhaboubi, and all of my current laboratory colleagues Dr. Wisam Hassan, Dr. Reem Elkalouby, Bonnie Gulas-Wroblewski, Rachel Cook, Wojciech Futoma, Roukaya Mabizari; as well colleagues and collaborators from numerous Departments for making my time at Texas A&M University a great experience. It also goes without saying how thankful and appreciative I am for my wife, Dr. Rachel Modarelli. She has been a shining example of excellence in academia, and a constant source of motivation as I pursued this degree. v CONTRIBUTORS AND FUNDING SOURCES Contributors This work was supervised by a dissertation committee consisting of Dr. Maria D. Esteve-Gasent (chair), Dr. James N. Derr (co-chair), and Dr. Pamela J. Ferro of the Department of Veterinary Pathobiology and Dr. John M. Tomeček of the Department of Wildlife and Fisheries Sciences (members). All work for this dissertation was completed independently under the supervision of Dr. Esteve-Gasent. Contributors include TVMDL, College Station, TX; Rocky Mountain Laboratories, Hamilton, Montana; UC Davis School of Veterinary Medicine, Davis, California; and USDA-ARS, Kerrville, TX. Funding Sources Graduate study was supported by Texas A&M AgriLife and Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) seed grant Molecular Diagnosis of Zoonotic Tick-Borne Diseases. vi NOMENCLATURE CDC Centers for Disease Control and Prevention CGE Canine granulocytic ehrlichiosis CME Canine monocytic ehrlichiosis cnPCR Conventional polymerase chain reaction Cq Quantification cycle DIVA Differentiating infected and vaccinated animals DNA Deoxyribonucleic acid EIPC Endogenous internal positive control ELISA Enzyme-linked immunosorbent assay GCE Genome copy equivalents GG Genomic groups HME Human monocytic ehrlichiosis IFA Immunofluorescence assay LD Lyme Disease PCR Polymerase chain reaction qPCR Quantitative real-time polymerase chain reaction RMSF Rocky Mountain spotted Fever SFGR Spotted fever group rickettsioses SNP Single nucleotide polymorphism TBD Tick-borne disease TBRF Tick-borne relapsing Fever vii TVMDL Texas A&M Veterinary Medical Diagnostic Laboratory Tm Melting temperature µl Microliter U.S. United States viii TABLE OF CONTENTS Page ABSTRACT .......................................................................................................................... ii DEDICATION ..................................................................................................................... iv ACKNOWLEDGEMENTS ...................................................................................................v CONTRIBUTORS AND FUNDING SOURCES ................................................................ vi NOMENCLATURE ............................................................................................................ vii TABLE OF CONTENTS ..................................................................................................... ix LIST OF FIGURES ............................................................................................................. xii LIST OF TABLES ............................................................................................................. xiii CHAPTER I INTRODUCTION AND LITERATURE REVIEW ........................................1 Tick-borne diseases affecting dogs ...................................................................................1 Borrelial pathogens............................................................................................................1 Borreliosis ....................................................................................................................2 Rickettsial pathogens .........................................................................................................8 Anaplasmosis................................................................................................................9 Rickettsiosis............................................................................................................... 12 Ehrlichiosis ................................................................................................................ 14 Babesial pathogens ..........................................................................................................19 Prevalence of tick-borne pathogens within Texas dogs ..................................................22 Significance to public health ...........................................................................................27 Limitations in detecting tick-borne pathogens ................................................................28 A brief history of molecular diagnostic tools ..................................................................32
Load more

Recommended publications
  • Colorado Ticks and Tick-Borne Diseases Fact Sheet No
    Colorado Ticks and Tick-Borne Diseases Fact Sheet No. 5.593 Insect Series|Trees and Shrubs by W.S. Cranshaw, F.B. Peairs and B.C. Kondratieff* Ticks are blood-feeding parasites of Quick Facts animals found throughout Colorado. They are particularly common at higher elevations. • The most common tick that Problems related to blood loss do occur bites humans and dogs among wildlife and livestock, but they are in Colorado is the Rocky rare. Presently 27 species of ticks are known Mountain wood tick. to occur in Colorado and Table 1 lists the more common ones. Almost all human • Rocky Mountain wood tick is encounters with ticks in Colorado involve most active and does most the Rocky Mountain wood tick. Fortunately, biting in spring, becoming some of the most important tick species dormant with warm weather in present elsewhere in the United States are summer. Figure 1: Adult Rocky Mountain wood tick prior either rare (lone star tick) or completely to feeding. Rocky Mountain wood tick is the most • Colorado tick fever is by far absent from the state (blacklegged tick). common tick that is found on humans and pets in Ticks most affect humans by their ability Colorado. the most common tick- to transmit pathogens that produce several transmitted disease of the important diseases. Diseases spread by ticks region. Despite its name, in Colorado include Colorado tick fever, Rocky Mountain spotted fever Rocky Mountain spotted fever, tularemia and is quite rare here. relapsing fever. • Several repellents are recommended for ticks Life Cycle of Ticks including DEET, picaridin, Two families of ticks occur in Colorado, Figure 2: Adult female and male of the Rocky IR3535, and oil of lemon hard ticks (Ixodidae family) and soft ticks Mountain wood tick.
    [Show full text]
  • Vaccination with the Variable Tick Protein of the Relapsing Fever Spirochete Borrelia Hermsii Protects Mice from Infection by Tick-Bite Benjamin J
    Krajacich et al. Parasites & Vectors (2015) 8:546 DOI 10.1186/s13071-015-1170-1 RESEARCH Open Access Vaccination with the variable tick protein of the relapsing fever spirochete Borrelia hermsii protects mice from infection by tick-bite Benjamin J. Krajacich1, Job E. Lopez2, Sandra J. Raffel3 and Tom G. Schwan3* Abstract Background: Tick-borne relapsing fevers of humans are caused by spirochetes that must adapt to both warm-blooded vertebrates and cold-blooded ticks. In western North America, most human cases of relapsing fever are caused by Borrelia hermsii, which cycles in nature between its tick vector Ornithodoros hermsi and small mammals such as tree squirrels and chipmunks. These spirochetes alter their outer surface by switching off one of the bloodstream- associated variable major proteins (Vmps) they produce in mammals, and replacing it with the variable tick protein (Vtp) following their acquisition by ticks. Based on this reversion to Vtp in ticks, we produced experimental vaccines comprised on this protein and tested them in mice challenged by infected ticks. Methods: The vtp gene from two isolates of B. hermsii that encoded antigenically distinct types of proteins were cloned, expressed, and the recombinant Vtp proteins were purified and used to vaccinate mice. Ornithodoros hermsi ticks that were infected with one of the two strains of B. hermsii from which the vtp gene originated were used to challenge mice that received one of the two Vtp vaccines or only adjuvant. Mice were then followed for infection and seroconversion. Results: The Vtp vaccines produced protective immune responses in mice challenged with O.
    [Show full text]
  • YES, WE DO HAVE TICKS in WASHINGTON: WHY THAT’S IMPORTANT and WHAT YOU SHOULD KNOW Liz Dykstra, Phd, BCE Public Health Entomologist Agenda
    YES, WE DO HAVE TICKS IN WASHINGTON: WHY THAT’S IMPORTANT AND WHAT YOU SHOULD KNOW Liz Dykstra, PhD, BCE Public Health Entomologist Agenda • Tick–borne disease in Washington • Tick Surveillance in Washington • Common Species • Pathogen Findings • Protective Measures Historical Pathogen Identifications Human and canine case reports of Lyme disease in WA, OR, CA, and BC Anaplasmosis reported in canines in WA, OR, CA, and BC; human case reports from CA Babesiosis reported in humans in WA and CA Rocky Mountain Spotted Fever (RMSF) historically reported in WA (Soft tick transmitted) Tick-borne relapsing fever (TBRF) commonly reported in WA* Tularemia commonly reported in WA, but not usually thought to be tick-borne Clinical under-recognition and under-reporting are suspected *No reported (hard tick transmitted) TBRF cases (caused by Borrelia miyamotoi) Locally Acquired Cases 12 10 8 Lyme 6 RMSF Relapsing Fever Case Count 4 Tularemia 2 0 2010 2011 2012 2013 2014 2015 2016 Reported Tick-Borne Disease Cases in Humans, Washington, 2018-2019 DISEASE 2018 2019 Tick-borne relapsing fever 2 3 Lyme disease 18 26 Tularemia** 3 3 Spotted Fever Rickettsiosis 0 3* Tick Paralysis 1 2 *First locally-acquired confirmed case of R. rickettsii in ~20 years **None tick-related Other Tick-borne Diseases Anaplasmosis o Anaplasma phagocytophilum o Only reported in dogs in Washington Hard tick-borne Relapsing fever o Borrelia miyamotoi o No reported cases in Washington Seasonality Lyme Tularemia 8 6 7 5 6 4 5 3 4 3 2 2 1 1 0 0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec RMSF 8 TBRF 2 7 6 5 4 1 3 2 1 0 0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Washington State Tick Surveillance Project Increase our understanding of tick species populations and distribution and risk of tick-borne diseases in Washington through collection, identification, and testing of ticks for pathogens of interest.
    [Show full text]
  • (Hard Ticks) and Argasidae (Soft Ticks) That Are of Public Health Importance
    CAUSAL AGENT There are many genera and species of ticks in the families Ixodidae (hard ticks) and Argasidae (soft ticks) that are of public health importance. Some representative genera, and diseases they are known vectors for, include: Amblyomma (tularemia, ehrlichiosis, Rocky Mountain spotted fever (RMSF), and boutonneuse fever); Dermacentor (RMSF, Colorado tick fever, tularemia, Siberian tick typhus, and Central European tick-borne encephalitis, as well as being an agent of tick paralysis); Hyalomma (Siberian tick typhus, Crimean- Congo hemorrhagic fever); Ixodes (Lyme disease, babesiosis, human granulocytic ehrlichiosis, and Russian spring-summer encephalitis); Rhipicephalus (RMSF and boutonneuse fever); Ornithodoros (tick-borne relapsing fever); Carios (tick-borne relapsing fever). Life Cycles Most tick species undergo one of four different life cycles. Members of the family Ixodidae undergo either one-host, two-host or three-host life cycles. During the one-host life cycle, ticks remain on the same host for the larval, nymphal and adult stages, only leaving the host prior to laying eggs. During the two-host life cycle, the tick molts from larva to nymph on the first host, but will leave the host between the nymphal and adult stages. The second host may be the same individual as the first host, the same species, or even a second species. Most ticks of public health importance undergo the three-host life cycle, whereby the tick leaves the host after the larval and nymphal stages. The three hosts are not always the same species, but may be the same species, or even the same individual, depending on host availability for the tick.
    [Show full text]
  • Tick-Borne Disease in California
    TICK-BORNE DISEASE IN CALIFORNIA SANTA CLARA COUNTY VECTOR CONTROL DISTRICT 1580 Berger Drive San Jose, CA 95112 (408) 918-4770 / 1(800) 675-1155 www.sccvector.org There are several established, and several newly emerging tick-borne diseases in California. While most of these diseases are rare, some can be severe and potentially fatal. It is important for you to familiarize yourself with the following symptoms and contact your physician should you suspect a tick-borne disease. LYME DISESASE Lyme disease is a bacteria disease and is the #1 tick-born disease in California. There are an average of 200 cases of Lyme disease reported in California each year. INCUBATION PERIOD 3-30 days (7-9 days average) SYMPTOMS Acute stage ► slowly, enlarging red flash (about the size of a half dollar or larger) occurs in 60-80% of adults, less in children. ►flu-like symptoms Chronic Stage ► months to years later ►migratory paint in joints, tendons, muscles & Diagnosis is by physician observation of typical rash or blood test. Treatment is with antibiotics. The tick vector in California is Ixodes pacificus, also known as the Western Black-legged Tick. RELAPSING FEVER This tick-borne bacterial disease occurs in California, with 0-22 cases reported each year. It is commonly found in coniferous (evergreen / pine) forest areas above 4,000 feet elevation. Increased incidence is observed in the summer months when vacationers open cabins and disturb the rodent reservoirs and the ticks. Although this disease can be fatal if untreated, fatalities have been rare. Diagnosis is by blood tests, with antibiotics as treatment.
    [Show full text]
  • Transcriptional and Genomic Analyses Reveal an Analogous Mechanism for a Piperidinyl
    Transcriptional and genomic analyses reveal an analogous mechanism for a Piperidinyl- Benzimidazolone analogue in Babesia divergens compared to other apicomplexans. by Ingrid Rossouw Submitted in partial fulfilment of the requirements for the degree Philosophiae Doctor In the faculty of Natural and Agricultural Science Department Genetics University of Pretoria Pretoria 2015 Supervisor: Prof. Christine Maritz-Olivier Co-supervisor: Prof. Lyn-Marie Birkholtz 1 Declaration I, Ingrid Rossouw, hereby declare that this dissertation submitted for the degree Philosophiae Doctor at the University of Pretoria, is my own work and has not previously been submitted for a degree at this, or any other university. Ingrid Rossouw Date 2 Plagiarism Declaration Full name: Ingrid Rossouw Student number: 24075681 Title of work: Transcriptional and genomic analyses reveal an analogous mechanism for a Piperidinyl-Benzimidazolone analogue in Babesia divergens compared to other apicomplexans. Declaration: 1. I understand what plagiarism entails and am aware of the University’s policy in this regard. 2. I declare that this thesis (eg. essay, report, project, assignment, dissertation, thesis etc.) is my own, original work. Where someone else’s work has been used (whether from a printed source, the internet or any other source) due acknowledgement was given and reference was made according to the departmental requirements. 3. I did not make use of another student’s previous work and submit it was my own. 4. I did not allow and will not allow anyone to copy my work with the intention of presenting it as his or her own work. 3 Dedication I would like to dedicate this work to the memory of my loving mother.
    [Show full text]
  • Climate Change and Its Impacts on Global Health
    The Pharma Innovation Journal 2019; 8(3): 316-326 ISSN (E): 2277- 7695 ISSN (P): 2349-8242 NAAS Rating: 5.03 Climate change and its impacts on global health: A TPI 2019; 8(3): 316-326 © 2019 TPI review www.thepharmajournal.com Received: 15-01-2019 Accepted: 20-02-2019 Vandita Mishra, Pankaj Kumar Patel, Bhoomika, Anjali, Ankit Shukla, Vandita Mishra Anshuk Sharma and Brijesh Patel Division of Livestock Products Technology, ICAR-IVRI, Abstract Izatnagar, Uttar Pradesh, India The early costs of global climate change (GCC) are well documented. However, future impacts on ecosystem health, and on the health of humans, domestic animals, and wildlife, are much less well Pankaj Kumar Patel Division of Medicine, ICAR- understood. Evidence of rising frequency of excessive weather events of geographic changes in vector- IVRI, Izatnagar, Uttar Pradesh, borne disease (VBD), and of altered animal behavioral responses deserves action. To make valid choices, India however, practitioners and decision makers must understand what is known about GCC. There will be a huge number of microbial, vectors, and host responses to climate change, for example, and not all Bhoomika organisms will respond similarly or across equal time scales. During the past 50 years or so, patterns of Division of Veterinary Public emerging arbovirus diseases have changed drastically. Climate change, especially increasing Health, ICAR-IVRI, Izatnagar, temperatures and rainfall is a major determining factor in the spastial and temporal distribution of life Uttar Pradesh, India cycles of arthropods and its association, evolution as well as transmission of emerging arboviruses to vertebrate hosts. Ecological disturbances, especially due to human intervention exert an influence on the Anjali emergence and proliferation of emerging and zoonotic diseases.
    [Show full text]
  • Arizona Animal Disease Refresher
    ZOONOTIC DISEASE UPDATES RABIES Rabies Background • Viral disease affecting all mammals (including humans) • Extremely high case fatality rate • Acute, progressive encephalomyelitis • After symptoms begin, clinical course is usually irreversible • With supportive care, most human patients die within 15 days after symptoms begin. Rabies causes inflammation of the brain and spinal cord. • Incubation period =1-3 months. Rabies Transmission • Infectious materials • Saliva • Central nervous system tissues and fluid • Usually through BITE of an infected animal • Other ways: • Contamination of mucous membranes, open wounds, or abrasions by infected tissues • Corneal transplant • Aerosol (caves) Rabies Variant Types Rabid Animals in Arizona: 2002–2014 300 250 200 150 100 Number of animals 50 0 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 Year Rabid Animals in Arizona: 2002–2014 300 Other 250 Fox Skunk 200 Bat 150 100 Number of animals 50 0 2008 2009 2010 2011 2012 2013 2014 Year Skunk Epizootic in Southern Arizona • During winter 2013, increased numbers of rabid skunks identified in Santa Cruz and Pima counties • Prevention efforts • Increase community awareness • Domestic animal vaccination campaigns • Skunk vaccination • Rabies quarantine in county Rabies Reminders • Ensure domestic animals are vaccinated for rabies • Public education to not touch wild animals (particularly bats, skunks, and foxes) • If potential exposure occurs, seek medical care and consult with local public health • Questions? TICK-BORNE RELAPSING FEVER
    [Show full text]
  • Ornithodoros Moubata
    Determination of tick-pathogen interactions during acquisition and transmission of Borrelia duttonii by Ornithodoros moubata Bachelor’s Thesis Laboratory of Molecular Ecology of Vectors and Pathogens Institute of Parasitology Biology Center, ASCR Student: Ana Cetkovic Supervisor: Ryan O.M. Rego, PhD České Budějovice 2020 Abstract The aim of this work was to investigate the acquisition and transmission dynamics of Borrelia duttonii, a common cause of relapsing fever in Africa, by the vector Ornithodoros moubata. We assessed the infectivity of frozen mouse sera and determined that no infection was established in a naïve host despite the fact that the survival of B. duttonii at -20°C over period of several months was confirmed. By needle inoculation of naïve mice with the infected, unfed tick-homogenate, we demonstrated that the expression of Vmp gene is continuously upregulated. We concluded that the Borrelia in unfed ticks are still infectious for a mammalian host over the course of several months. In addition, we attempted to quantify the level of Vtp expression by real-time, quantitative PCR. The efficiency of acquisition of B. duttonii Ly isolate by O. moubata was determined to be considerably low. Its transmission dynamics by O. moubata was investigated as well. The infectivity and acquisition of B. duttonii 1120K3 and Ly isolates were compared and the observed differences were identified. Furthermore, we evaluated the acquisition ability of B. duttonii 1120K3 by O. moubata by allowing ticks to feed on infected mice. We determined the acquisition time threshold of 2.5 minutes. The sensitivity of Borrelia to various animal sera was assessed.
    [Show full text]
  • Muzaffarpur, India, 2013–2014
    Morbidity and Mortality Weekly Report Weekly / Vol. 64 / No. 3 January 30, 2015 Outbreaks of Unexplained Neurologic Illness — Muzaffarpur, India, 2013–2014 Aakash Shrivastava, MD1, Padmini Srikantiah, MD2,3, Anil Kumar, MD1, Gyan Bhushan, MD4, Kapil Goel, MD5, Satish Kumar, MD5, Tripurari Kumar, MBBS5, Raju Mohankumar, MBBS5, Rajesh Pandey, MBBS5, Parvez Pathan, MBBS5, Yogita Tulsian, MBBS5, Mohan Pappanna, MD6, Achhelal Pasi, MD6, Arghya Pradhan, MBBS6, Pankaj Singh, MBBS6, D. Somashekar, MD6, Anoop Velayudhan, MBBS6, Rajesh Yadav, MBBS6, Mala Chhabra, MD1, Veena Mittal, MD1, Shashi Khare, MD1, James J Sejvar, MD7, Mayank Dwivedi, MD2, Kayla Laserson, ScD2,3, Kenneth C. Earhart, MD2,3, P. Sivaperumal, PhD8, A. Ramesh Kumar, PhD8, Amit Chakrabarti, MD8, Jerry Thomas, MD9, Joshua Schier, MD9, Ram Singh, PhD1, Ravi Shankar Singh, MD1, A.C. Dhariwal, MD10, L.S. Chauhan, MD1 (Author affiliations at end of text) Outbreaks of an unexplained acute neurologic illness affect- 2013 Outbreak Investigation ing young children and associated with high case-fatality rates During May 17–July 22, 2013, a total of 133 children were have been reported in the Muzaffarpur district of Bihar state admitted to the two main referral hospitals in Muzaffarpur in India since 1995. The outbreaks generally peak in June and with illnesses that met the investigation case definition of decline weeks later with the onset of monsoon rains. There have acute onset seizures or altered mental status within 7 days been multiple epidemiologic and laboratory investigations of of admission in a child aged <15 years. Of these, 94 (71%) this syndrome, leading to a wide spectrum of proposed causes for the illness, including infectious encephalitis and exposure INSIDE to pesticides.
    [Show full text]
  • 46 – Ticks, Mites, Lice and the Diseases They Transmit Speaker
    46 –Ticks, Mites, Lice and The Diseases They Transmit Speaker: Paul G. Auwaerter, MD Disclosures of Financial Relationships with Relevant Commercial Interests • Scientific Advisory Board – DiaSorin, Adaptive BioTherapeutics Ticks, Mites, Lice, and The Diseases They Transmit • Grantee – MicroBplex, NIH/SBIR (Lyme disease diagnostics) • Equity – JNJ Paul G. Auwaerter, MD Sherrilyn and Ken Fisher Professor of Medicine Clinical Director, Division of Infectious Diseases Johns Hopkins University School of Medicine PA1 Why the board exam loves these infections PLAY THE MATCH GAME Condition Pathogen Condition Match to the Pathogen • Scrub typhus • Rickettsia conorii • Scrub typhus • Rickettsia conorii • Louse-borne relapsing • Rickettsia prowazekii • Louse-borne relapsing fever • Rickettsia prowazekii fever • Borrelia recurrentis • Tick-borne relapsing fever • Borrelia recurrentis • Tick-borne relapsing fever • Borrelia hermsii • Boutonneuse (Mediterranean) fever • Borrelia hermsii • Boutonneuse • Borrelia turicatae • Borrelia turicatae (Mediterranean) fever • Louse-borne epidemic typhus • Rickettsia typhi • Endemic (murine) typhus • Rickettsia typhi • Louse-borne epidemic • Orientia tsutsugamushi typhus • Orientia tsutsugamushi • Endemic (murine) typhus Tick-borne Diseases of North America Tick-borne Diseases of North America General Principles I General Principles II Seasonal but not always • Initial, early presentation non-specific: Geography informs etiology but often changes over time • “Flu-like illness” (e.g. fever, headache, myalgia)
    [Show full text]
  • Appendix 1 Signs and Symptoms of Arthropod-Borne Diseases
    Appendix 1 Signs and Symptoms of Arthropod-Borne Diseases The following is an alphabetical listing of common signs and symptoms of arthropod- borne diseases. Unfortunately, few signs and symptoms are specific to any one disease. Further differentiation by appropriate laboratory or radiologic tests may be needed. By no means should this listing be considered as a complete differential diagnosis of any of the symptoms discussed. Adenopathy: Generalized adenopathy may occur in the early stages of African trypanosomiasis – the glands of the posterior cervical triangle being most conspicuously affected (Winterbottom’s sign). Adenopathy may also be seen in the acute stage of Chagas’ disease. Anemia: Anemia may be seen in cases of malaria, babesiosis, and trypanosomiasis. Anemia can be especially severe in fal- ciparum malaria. Blister: A blister may occur at arthropod bite sites. Blistering may also occur as a result from blister beetles contacting human skin. Bulls-Eye Rash (see Erythema Migrans) Chagoma: An indurated, erythematous lesion may occur on the body – often head or neck – caused by Trypanosoma cruzi infection (Chagas’disease). A chagoma may persist for 2–3 mo. Chyluria: The presence of chyle (lymphatic fluid) in the urine is often seen in lymphatic filariasis. Urine may be milky white and even contain microfilariae. Coma: Sudden coma in a person returning from a malarious area may indicate cerebral malaria. African trypanosomiasis (sleeping sickness) may also lead to coma after a long period of increasingly severe symptoms of meningoen- cephalitis. Rocky Mountain Spotted Fever and other rickettsial infections may also lead to coma. 227 228 Appendix 1 Conjunctivitis: Chagas’ disease and onchocerciasis may lead to chronic conjunctivitis.
    [Show full text]