Babesiosis Emergence in the United States

Summary

Principal Investigator: MARIA ANA DIUK-WASSER
Abstract: PROJECT SUMMARY Intellectual Merit: Human babesiosis is a rapidly emerging tick-borne zoonosis in the United States caused by the protozoan Babesia microti and transmitted by Ixodes scapularis, the Lyme disease vector. Unlike Lyme disease, babesiosis is a potentially fatal disease and poses a threat to blood transfusion recipients. In the Northeast, both Lyme disease and babesiosis were originally restricted to coastal New England. While Lyme disease has expanded dramatically over the past thirty years and now is endemic from Maine to Virginia, babesiosis cases appears to be expanding at a slower rate for reasons that are not understood. This differential spread provides a unique opportunity to examine factors driving pathogen emergence by comparing these species'natural history and transmission dynamics. Furthermore, because B. microti encounters a large proportion of host populations already infected with 6. /jurgdor/er/throughout its geographic expansion, the goal ofthis study is to investigate how pathogen interactions at the individual, population, and community levels influence B. microti invasion patterns and enzootic prevalence. Evidence for a mutualistic effect of B. burgdorferi infection on B. m/crof/transmission are based on recent findings by .Diuk- Wasser and collaborators that coinfected hosts produce more S. m/crof/-infected ticks than 6. /77/crof/-only infected hosts in laboratory studies and that tick infection prevalence and human disease can be as high for 6. microti than B. burgdorferi at long-established sites. This project will directly compare transmission rates of both B. microti and B. burgdorferi in the laboratory by employing established colonies of /. scapularis and white-footed mice {Peromyscus leucopus) and will explore how host coinfection with both pathogens enhances B. m/crof/transmission (Aim 1). Scaling up from this system, Ro will be estimated for populations of infected and non-infected hosts to determine the extent to which coinfection drives invasion of B. microti into previously uninfected areas (Aim 2). A dynamic multi-host, multi-pathogen model will be developed to identify key factors determining B. microti infection prevalence in host-seeking nymphs once B. microti has become established (Aim 3). The proposed project is innovative because it investigates the drivers of an active invasion process for an emerging human pathogen;uses a comparative approach to identify key determinants ofthe invasion and persistence of two /. scapularls-borne pathogens;and examines the role of mutualistic interactions among vector-borne pathogens in invasion and persistence. Expected outcomes include elucidation ofthe mechanisms determining human exposure risk to a rapidly emerging, potentially lethal tick-borne pathogen, and the development of a transmission model including the effect of pathogen interactions. A long-term goal of this study is to develop optimal prevention and control strategies that can synergistically target 6. microti and 6. burgdorferi, as well as other known, or new, tick-borne pathogens. [unreadable] Broader Impacts: This project will employ one postdoctoral researcher, one PhD student researcher and three field assistants, as well as two high-school students from the Yale University Peabody Museum of Natural History Evolutions school program through an after school program for underserved populations with a demonstrated interest in the natural and environmental sciences. Yale undergraduate and Master's of Public Health students will be exposed to the findings ofthe research through Dr. Diuk-Wasser's Eco-Epidemiology course and will be encouraged to pursue undergraduate/MPH theses on different aspects of the project, providing a unique opportunity for bridging ecological and epidemiological concepts. This project will make an important and novel contribution to public health by elucidating the ecological mechanisms of spread and persistence of the human babesiosis and Lyme disease agents. The results from our studies will be disseminated among a wide variety of scientific journals, and will be presented at scientific meetings that target ecologists, evolutionary biologists, mathematical modelers, and public health scientists. The results will also be disseminated widely to popular media outlets through press releases and interviews upon the publication of important findings, as well as through independent organizations, such as the American Lyme Disease Foundation and through the Lyme disease iPhone App. This project will make an important and novel contribution to public health by elucidating ecological mechanisms of persistence and spread of the agents of human babesiosis and Lyme disease. It will help increase public and physician's awareness ofthe emerging risk of babesiosis and the probability of coinfection causing more serious symptoms than either disease alone. Development of a study design and modeling framework for the study of interactions among multiple pathogens will also inform studies of a range of pathogens typically studied in isolation.
Funding Period: 2012-09-10 - 2017-08-31
more information: NIH RePORT

Top Publications

  1. pmc A simple model for the establishment of tick-borne pathogens of Ixodes scapularis: a global sensitivity analysis of R0
    J M Dunn
    School of Mathematical and Geospatial Sciences, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia
    J Theor Biol 335:213-21. 2013
  2. pmc Quantitative PCR for detection of Babesia microti in Ixodes scapularis ticks and in human blood
    Lindsay Rollend
    1 Department of Epidemiology and Public Health, Yale School of Public Health, New Haven, Connecticut
    Vector Borne Zoonotic Dis 13:784-90. 2013

Detail Information

Publications3

  1. pmc A simple model for the establishment of tick-borne pathogens of Ixodes scapularis: a global sensitivity analysis of R0
    J M Dunn
    School of Mathematical and Geospatial Sciences, RMIT University, GPO Box 2476, Melbourne, Victoria 3001, Australia
    J Theor Biol 335:213-21. 2013
    ....
  2. pmc Quantitative PCR for detection of Babesia microti in Ixodes scapularis ticks and in human blood
    Lindsay Rollend
    1 Department of Epidemiology and Public Health, Yale School of Public Health, New Haven, Connecticut
    Vector Borne Zoonotic Dis 13:784-90. 2013
    ..Finally, we report the prevalence of B. microti infection in field-collected I. scapularis nymphs from three locations in southern New England that present disparate incidences of human babesiosis...

Research Grants30

  1. Comparative Biology of Tissue Repair, Regeneration and Aging
    Kevin Strange; Fiscal Year: 2013
    ..The proposed COBRE will greatly enhance MDIBL's growth and development, which in turn will contribute to the continued growth and enhancement of the biomedical research infrastructure in Maine. ..
  2. MACHINE LEARNING TO FORECAST ZOONOTIC DISEASE EMERGENCE
    Barbara A Han; Fiscal Year: 2013
    ..Ultimately, research proposed herein will provide a basis for predicting the geographic locations, infectious agents, and animal reservoirs from which future zoonoses will emerge. ..
  3. Delivery system development for a reservoir targeted Lyme disease vaccine
    Linden T Hu; Fiscal Year: 2013
    ..Development of reservoir targeted vaccine strategies for controlling vector transmitted diseases will be an important addition to the armamentarium for prevention of human Lyme disease. ..
  4. The Virtual Physiological Rat Project
    Daniel A Beard; Fiscal Year: 2013
    ..This proposal targets the grand challenge of understanding complex multi-faceted disease phenotypes through experiments and simulations that capture the complex genotype-environment-phenotype relationship. ..
  5. Peruvian/Brazilian Amazon Center of Excellence in Malaria
    Joseph M Vinetz; Fiscal Year: 2013
    ..We hypothesize that asymptomatic infections may represent a major reservoir of parasites in this region, which is not addressed by traditional malaria control strategies. ..
  6. Research Center for Pharmacology &Drug Toxicology
    L Jackson Roberts; Fiscal Year: 2013
    ....
  7. Pacific NorthWest Regional Center of Excellence (PNWRCE)
    Jay A Nelson; Fiscal Year: 2013
    ..pseudomallei host pathogen response during both the septicemic as well as the intracellular phases of the disease. ..
  8. Southeast Regional Centers of Excellence for Biodefense &Emerging Infectious Di
    Philip Frederick Sparling; Fiscal Year: 2013
    ..SERCEB brings new investigators to the biodefense effort through a combination of educational programs, support of innovative new projects, and the synergistic interactions among its world-class investigators. ..
  9. New England Regional Center of Excellence in Biodefense and Emerging Infectious D
    Dennis L Kasper; Fiscal Year: 2013
    ..NERCE will also continue its Developmental Projects program and Career Development in Biodefense program in an effort to initiate new research efforts and to attract new investigators to this field. ..
  10. Elucidating Risks: From Exposure and Mechanism to Outcome
    James A Swenberg; Fiscal Year: 2013
    ..This Program is highly relevant to Superfund by addressing high-priority chemicals and by focusing on mechanisms underlying health effects, exposure assessment, and remediation to mitigate exposure and toxicity. ..
  11. Superfund Metal Mixtures, Biomarkers and Neurodevelopment
    David C Bellinger; Fiscal Year: 2013
    ..Aim 4- To promote rapid dissemination of significant research findings;and Aim 5- Compliance- To ensure compliance with NIH requirements for data and resource-sharing and the human and animal institutional review board requirements ..
  12. Rocky Mountain Regional Center of Excellence or Biodefense and Emerging Infectiou
    John T Belisle; Fiscal Year: 2013
    ..abstract_text> ..
  13. Dissemination of Evidence-Based Health Disparity Interventions
    Ashwini Sehgal; Fiscal Year: 2013
    ..abstract_text> ..