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Hornbostel VL, Meek JI, Hansen AP, Niesobecki SA, Nawrocki CC, Hinckley AF, Connally NP. Operational Considerations for Using Deer-Targeted 4-Poster Tick Control Devices in a Tick-borne Disease Endemic Community. JOURNAL OF PUBLIC HEALTH MANAGEMENT AND PRACTICE 2024; 30:111-121. [PMID: 37566802 PMCID: PMC10840788 DOI: 10.1097/phh.0000000000001809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/13/2023]
Abstract
CONTEXT In the northeastern United States, recommendations to prevent diseases spread by black-legged ticks ( Ixodes scapularis ) and lone star ticks ( Amblyomma americanum ) often rely on individuals to use personal protection or yard-based strategies. The 4-Poster deer treatment stations (4-Posters) suppress tick populations by treating deer hosts with acaricide, potentially offering a community-wide approach for reducing tick-borne diseases in endemic areas. The 4-Poster deployment logistics in mainland community settings are not well documented but are needed for future public health tick control efforts. PROGRAM As part of a public health research effort to design a population-based 4-Poster effectiveness study aimed at reducing tick-borne disease incidence, TickNET researchers partnered with the Town of Ridgefield (Connecticut) to understand the feasibility and operational logistics of deploying 4-Posters on public land within a residential community to inform future public health interventions by municipalities or vector control agencies. IMPLEMENTATION We deployed three 4-Posters on a municipal property from July to December 2020 and used motion-activated cameras to record wildlife activity nearby. We documented per-device operational details, costs, materials consumed, and animal activity. EVALUATION Operation of 4-Posters was feasible, and device challenges were easily remedied. Deer visitation and heavy nontarget animal use were documented at all devices. Unexpectedly, monthly corn consumption was not correlated with monthly deer-view days. The monthly cost per device was US $1279 or US $305 per hectare with an average 21 minutes of weekly service time. DISCUSSION Use of 4-Posters by communities, public health agencies, or vector control programs may be a practicable addition to tick management programs in tick-borne disease endemic areas in the Northeast. Such programs should carefully consider local and state regulations, follow manufacturer and pesticide label guidelines, and include wildlife monitoring. High labor costs incurred in this project could be mitigated by training vector control agency or municipality staff to service 4-Posters.
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Affiliation(s)
- Victoria L Hornbostel
- Department of Biology, Western Connecticut State University, Danbury, Connecticut (Ms Hornbostel and Dr Connally); Connecticut Emerging Infections Program, Yale School of Public Health, New Haven, Connecticut (Mr Meek and Mss Hansen and Niesobecki); and Division of Vector-Borne Disease, Centers for Disease Control and Prevention, Fort Collins, Colorado (Ms Nawrocki and Dr Hinckley)
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Nawrocki CC, Piedmonte N, Niesobecki SA, Rowe A, Hansen AP, Kaufman A, Foster E, Meek JI, Niccolai L, White J, Backenson B, Eisen L, Hook SA, Connally NP, Hornbostel VL, Hinckley AF. Acceptability of 4-poster deer treatment devices for community-wide tick control among residents of high Lyme disease incidence counties in Connecticut and New York, USA. Ticks Tick Borne Dis 2023; 14:102231. [PMID: 37531890 PMCID: PMC10883357 DOI: 10.1016/j.ttbdis.2023.102231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 06/12/2023] [Accepted: 07/14/2023] [Indexed: 08/04/2023]
Abstract
The 4-Poster Tick Control Deer Feeder (4-poster) device applies acaricide to white-tailed deer (Odocoileus virginianus) and can reduce populations of the blacklegged tick (Ixodes scapularis), which transmits the agents of Lyme disease, anaplasmosis, babesiosis, and Powassan virus disease in the Northeastern United States. While 4-poster devices have the potential to provide community-wide management of blacklegged ticks in Lyme disease endemic areas, no recent study has assessed their acceptability among residents. We conducted a survey of residents from 16 counties with high annual average Lyme disease incidence (≥ 10 cases per 100,000 persons between 2013 and 2017) in Connecticut and New York to understand perceptions and experiences related to tickborne diseases, support or concerns for placement of 4-poster devices in their community, and opinions on which entities should be responsible for tick control on private properties. Overall, 37% of 1652 respondents (5.5% response rate) would support placement of a 4-poster device on their own property, 71% would support placement on other private land in their community, and 90% would support placement on public land. Respondents who were male, rented their property, resided on larger properties, or were very or extremely concerned about encountering ticks on their property were each more likely to support placement of 4-poster devices on their own property. The primary reason for not supporting placement of a 4-poster device on one's own property was the need for weekly service visits from pest control professionals, whereas the top reason for not supporting placement on other land (private or public) was safety concerns. Most respondents (61%) felt property owners should be responsible for tick control on private properties. Communities considering 4-poster devices as part of a tick management strategy should consider targeting owners of larger properties and placing devices on public lands.
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Affiliation(s)
- Courtney C Nawrocki
- Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA.
| | - Nicholas Piedmonte
- Bureau of Communicable Disease Control, New York State Department of Health, Albany, NY, USA
| | - Sara A Niesobecki
- Connecticut Emerging Infections Program, Yale School of Public Health, New Haven, CT, USA
| | - Adam Rowe
- Bureau of Communicable Disease Control, New York State Department of Health, Albany, NY, USA
| | - AmberJean P Hansen
- Connecticut Emerging Infections Program, Yale School of Public Health, New Haven, CT, USA
| | - Alison Kaufman
- Bureau of Communicable Disease Control, New York State Department of Health, Albany, NY, USA
| | - Erik Foster
- Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - James I Meek
- Connecticut Emerging Infections Program, Yale School of Public Health, New Haven, CT, USA
| | - Linda Niccolai
- Connecticut Emerging Infections Program, Yale School of Public Health, New Haven, CT, USA
| | - Jennifer White
- Bureau of Communicable Disease Control, New York State Department of Health, Albany, NY, USA
| | - Bryon Backenson
- Bureau of Communicable Disease Control, New York State Department of Health, Albany, NY, USA
| | - Lars Eisen
- Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Sarah A Hook
- Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Neeta P Connally
- Department of Biology, Western Connecticut State University, Danbury, CT, USA
| | | | - Alison F Hinckley
- Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
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Schulze TL, Eisen L, Russell K, Jordan RA. Community-based integrated tick management programs: cost and feasibility scenarios. JOURNAL OF MEDICAL ENTOMOLOGY 2023; 60:1048-1060. [PMID: 37540592 PMCID: PMC10862372 DOI: 10.1093/jme/tjad093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 06/22/2023] [Accepted: 06/30/2023] [Indexed: 08/06/2023]
Abstract
Numerous studies have assessed the efficacy of environmentally based control methods to suppress populations of the blacklegged tick (Ixodes scapularis Say), but few of these estimated the cost of control. We estimated costs for a range of tick control methods (including habitat management, deer exclusion or population reduction, broadcast of acaricides, and use of host-targeted acaricides) implemented singly or in combination and applied to a model community comprising 320 residential properties and parklands. Using the high end for cost ranges, tick control based on a single method was estimated to have mean annual costs per household in the model community ranging from $132 for treating only forest ecotone with a broadcast synthetic acaricide to kill host-seeking ticks (or $404 for treating all residential forested habitat) to >$2,000 for deployment of bait boxes (SELECT TCS) across all residential tick habitat to treat rodents topically with acaricide to kill infesting ticks. Combining different sets of multiple methods in an integrated tick management program placed the annual cost between $508 and 3,192 annually per household in the model community, underscoring the disconnect between what people in Lyme disease endemic areas say they are willing to pay for tick control (not more than $100-150 annually) and the actual costs for tick control. Additional barriers to implementing community-based tick management programs within residential communities are discussed.
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Affiliation(s)
- Terry L. Schulze
- Terry L. Schulze, Ph.D., Inc., 9 Evergreen Court, Perrineville, NJ 08535, USA
| | - Lars Eisen
- Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 3156 Rampart Road, Fort Collins, CO 80521, USA
| | | | - Robert A. Jordan
- Monmouth County Mosquito Control Division, 1901 Wayside Road, Tinton Falls, NJ 07724, USA
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Tsao JI, Hamer SA, Han S, Sidge JL, Hickling GJ. The Contribution of Wildlife Hosts to the Rise of Ticks and Tick-Borne Diseases in North America. JOURNAL OF MEDICAL ENTOMOLOGY 2021; 58:1565-1587. [PMID: 33885784 DOI: 10.1093/jme/tjab047] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Indexed: 05/09/2023]
Abstract
Wildlife vertebrate hosts are integral to enzootic cycles of tick-borne pathogens, and in some cases have played key roles in the recent rise of ticks and tick-borne diseases in North America. In this forum article, we highlight roles that wildlife hosts play in the maintenance and transmission of zoonotic, companion animal, livestock, and wildlife tick-borne pathogens. We begin by illustrating how wildlife contribute directly and indirectly to the increase and geographic expansion of ticks and their associated pathogens. Wildlife provide blood meals for tick growth and reproduction; serve as pathogen reservoirs; and can disperse ticks and pathogens-either through natural movement (e.g., avian migration) or through human-facilitated movement (e.g., wildlife translocations and trade). We then discuss opportunities to manage tick-borne disease through actions directed at wildlife hosts. To conclude, we highlight key gaps in our understanding of the ecology of tick-host interactions, emphasizing that wildlife host communities are themselves a very dynamic component of tick-pathogen-host systems and therefore complicate management of tick-borne diseases, and should be taken into account when considering host-targeted approaches. Effective management of wildlife to reduce tick-borne disease risk further requires consideration of the 'human dimensions' of wildlife management. This includes understanding the public's diverse views and values about wildlife and wildlife impacts-including the perceived role of wildlife in fostering tick-borne diseases. Public health agencies should capitalize on the expertise of wildlife agencies when developing strategies to reduce tick-borne disease risks.
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Affiliation(s)
- Jean I Tsao
- Department of Fisheries and Wildlife, Department of Large Animal Clinical Sciences, Michigan State University, East Lansing, MI, USA
| | - Sarah A Hamer
- Department of Veterinary Integrative Biosciences, and Schubot Center for Avian Health, Department of Veterinary Pathology, Texas A&M University, College Station, TX, USA
| | - Seungeun Han
- Department of Disease Control and Epidemiology, National Veterinary Institute (SVA), Uppsala, Sweden
| | - Jennifer L Sidge
- Michigan Department of Agriculture and Rural Development, Lansing, MI, USA
| | - Graham J Hickling
- Center for Wildlife Health, Department of Forestry, Wildlife and Fisheries, University of Tennessee, Knoxville, TN, USA
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Kim TK, Tirloni L, Bencosme-Cuevas E, Kim TH, Diedrich JK, Yates JR, Mulenga A. Borrelia burgdorferi infection modifies protein content in saliva of Ixodes scapularis nymphs. BMC Genomics 2021; 22:152. [PMID: 33663385 PMCID: PMC7930271 DOI: 10.1186/s12864-021-07429-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 02/08/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Lyme disease (LD) caused by Borrelia burgdorferi is the most prevalent tick-borne disease. There is evidence that vaccines based on tick proteins that promote tick transmission of B. burgdorferi could prevent LD. As Ixodes scapularis nymph tick bites are responsible for most LD cases, this study sought to identify nymph tick saliva proteins associated with B. burgdorferi transmission using LC-MS/MS. Tick saliva was collected using a non-invasive method of stimulating ticks (uninfected and infected: unfed, and every 12 h during feeding through 72 h, and fully-fed) to salivate into 2% pilocarpine-PBS for protein identification using LC-MS/MS. RESULTS We identified a combined 747 tick saliva proteins of uninfected and B. burgdorferi infected ticks that were classified into 25 functional categories: housekeeping-like (48%), unknown function (18%), protease inhibitors (9%), immune-related (6%), proteases (8%), extracellular matrix (7%), and small categories that account for <5% each. Notably, B. burgdorferi infected ticks secreted high number of saliva proteins (n=645) than uninfected ticks (n=376). Counter-intuitively, antimicrobial peptides, which function to block bacterial infection at tick feeding site were suppressed 23-85 folds in B. burgdorferi infected ticks. Similar to glycolysis enzymes being enhanced in mammalian cells exposed to B. burgdorferi : eight of the 10-glycolysis pathway enzymes were secreted at high abundance by B. burgdorferi infected ticks. Of significance, rabbits exposed to B. burgdorferi infected ticks acquired potent immunity that caused 40-60% mortality of B. burgdorferi infected ticks during the second infestation compared to 15-28% for the uninfected. This might be explained by ELISA data that show that high expression levels of immunogenic proteins in B. burgdorferi infected ticks. CONCLUSION Data here suggest that B. burgdorferi infection modified protein content in tick saliva to promote its survival at the tick feeding site. For instance, enzymes; copper/zinc superoxide dismutase that led to production of H2O2 that is toxic to B. burgdorferi were suppressed, while, catalase and thioredoxin that neutralize H2O2, and pyruvate kinase which yields pyruvate that protects Bb from H2O2 killing were enhanced. We conclude data here is an important resource for discovery of effective antigens for a vaccine to prevent LD.
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Affiliation(s)
- Tae Kwon Kim
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, Texas, United States of America
- Department of Diagnostic Medicine and Veterinary Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas, United States of America
| | - Lucas Tirloni
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, Texas, United States of America
- Laboratory of Bacteriology, National Institute of Allergy and Infectious Diseases, Hamilton, Montana, United States of America
| | - Emily Bencosme-Cuevas
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, Texas, United States of America
| | - Tae Heung Kim
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, Texas, United States of America
| | - Jolene K Diedrich
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States of America
- Mass Spectrometry Core, Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - John R Yates
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, United States of America
| | - Albert Mulenga
- Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station, Texas, United States of America.
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Williams SC, Stafford KC, Linske MA, Brackney DE, LaBonte AM, Stuber HR, Cozens DW. Effective control of the motile stages of Amblyomma americanum and reduced Ehrlichia spp. prevalence in adults via permethrin treatment of white-tailed deer in coastal Connecticut, USA. Ticks Tick Borne Dis 2021; 12:101675. [PMID: 33529986 DOI: 10.1016/j.ttbdis.2021.101675] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 01/13/2021] [Accepted: 01/13/2021] [Indexed: 10/22/2022]
Abstract
The lone star tick, Amblyomma americanum, is a common human-biting species whose range has been largely restricted to the southeastern United States, until recent detections of established populations on Long Island, New York and throughout coastal southern New England. We evaluated the effectiveness of topical treatment of 10 % permethrin delivered via 4-poster devices to white-tailed deer, Odocoileus virginianus, in the management of a newly discovered A. americanum population in Norwalk, Connecticut. Using a high-density deployment of one 4-poster device/12.7 ha, we were successful in significantly reducing densities of host-seeking adults (93 % reduction), nymphs (92 %), and larvae (96 %) from 2018 to 2020. We also documented a significant reduction (87 %) in parasitizing adults and nymphs on white-tailed deer from 2018 to 2019. The prevalence of Ehrlichia chaffeensis and Ehrlichia ewingii combined in host-seeking adults declined significantly from 47 % at the time the A. americanum population was discovered in 2017 to 7% in 2020. However, the prevalence in nymphs remained static (∼9%) throughout the study period. These data demonstrate that, when properly deployed in a density-dependent manner in terms of deer abundance, 4-poster devices can effectively manage parasitizing and host-seeking A. americanum populations and reduce the prevalence of two ehrlichial species of public health importance.
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Affiliation(s)
- Scott C Williams
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT, 06504, United States; Department of Forestry and Horticulture, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT, 06504, United States.
| | - Kirby C Stafford
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT, 06504, United States; Department of Entomology, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT, 06504, United States.
| | - Megan A Linske
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT, 06504, United States; Department of Entomology, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT, 06504, United States.
| | - Douglas E Brackney
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT, 06504, United States; Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT, 06504, United States.
| | - Andrew M LaBonte
- Connecticut Department of Energy and Environmental Protection, Wildlife Division, 391 Route 32, North Franklin, CT, 06254, United States.
| | - Heidi R Stuber
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT, 06504, United States; Department of Entomology, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT, 06504, United States.
| | - Duncan W Cozens
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT, 06504, United States; Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT, 06504, United States.
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Grabowski JM, Hill CA. A Roadmap for Tick-Borne Flavivirus Research in the "Omics" Era. Front Cell Infect Microbiol 2017; 7:519. [PMID: 29312896 PMCID: PMC5744076 DOI: 10.3389/fcimb.2017.00519] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2017] [Accepted: 12/05/2017] [Indexed: 12/30/2022] Open
Abstract
Tick-borne flaviviruses (TBFs) affect human health globally. Human vaccines provide protection against some TBFs, and antivirals are available, yet TBF-specific control strategies are limited. Advances in genomics offer hope to understand the viral complement transmitted by ticks, and to develop disruptive, data-driven technologies for virus detection, treatment, and control. The genome assemblies of Ixodes scapularis, the North American tick vector of the TBF, Powassan virus, and other tick vectors, are providing insights into tick biology and pathogen transmission and serve as nucleation points for expanded genomic research. Systems biology has yielded insights to the response of tick cells to viral infection at the transcript and protein level, and new protein targets for vaccines to limit virus transmission. Reverse vaccinology approaches have moved candidate tick antigenic epitopes into vaccine development pipelines. Traditional drug and in silico screening have identified candidate antivirals, and target-based approaches have been developed to identify novel acaricides. Yet, additional genomic resources are required to expand TBF research. Priorities include genome assemblies for tick vectors, “omic” studies involving high consequence pathogens and vectors, and emphasizing viral metagenomics, tick-virus metabolomics, and structural genomics of TBF and tick proteins. Also required are resources for forward genetics, including the development of tick strains with quantifiable traits, genetic markers and linkage maps. Here we review the current state of genomic research on ticks and tick-borne viruses with an emphasis on TBFs. We outline an ambitious 10-year roadmap for research in the “omics era,” and explore key milestones needed to accomplish the goal of delivering three new vaccines, antivirals and acaricides for TBF control by 2030.
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Affiliation(s)
- Jeffrey M Grabowski
- Biology of Vector-Borne Viruses Section, Laboratory of Virology, Rocky Mountain Laboratories, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, United States
| | - Catherine A Hill
- Department of Entomology, Purdue University, West Lafayette, IN, United States.,Purdue Institute of Inflammation, Immunology and Infectious Disease, Purdue University, West Lafayette, IN, United States
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Eisen RJ, Eisen L, Beard CB. County-Scale Distribution of Ixodes scapularis and Ixodes pacificus (Acari: Ixodidae) in the Continental United States. JOURNAL OF MEDICAL ENTOMOLOGY 2016; 53:349-86. [PMID: 26783367 PMCID: PMC4844559 DOI: 10.1093/jme/tjv237] [Citation(s) in RCA: 197] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The blacklegged tick, Ixodes scapularis Say, is the primary vector to humans in the eastern United States of the Lyme disease spirochete Borrelia burgdorferi, as well as causative agents of anaplasmosis and babesiosis. Its close relative in the far western United States, the western blacklegged tick Ixodes pacificus Cooley and Kohls, is the primary vector to humans in that region of the Lyme disease and anaplasmosis agents. Since 1991, when standardized surveillance and reporting began, Lyme disease case counts have increased steadily in number and in geographical distribution in the eastern United States. Similar trends have been observed for anaplasmosis and babesiosis. To better understand the changing landscape of risk of human exposure to disease agents transmitted by I. scapularis and I. pacificus, and to document changes in their recorded distribution over the past two decades, we updated the distribution of these species from a map published in 1998. The presence of I. scapularis has now been documented from 1,420 (45.7%) of the 3,110 continental United States counties, as compared with 111 (3.6%) counties for I. pacificus. Combined, these vectors of B. burgdorferi and other disease agents now have been identified in a total of 1,531 (49.2%) counties spread across 43 states. This marks a 44.7% increase in the number of counties that have recorded the presence of these ticks since the previous map was presented in 1998, when 1,058 counties in 41 states reported the ticks to be present. Notably, the number of counties in which I. scapularis is considered established (six or more individuals or one or more life stages identified in a single year) has more than doubled since the previous national distribution map was published nearly two decades ago. The majority of county status changes occurred in the North-Central and Northeastern states, whereas the distribution in the South remained fairly stable. Two previously distinct foci for I. scapularis in the Northeast and North-Central states appear to be merging in the Ohio River Valley to form a single contiguous focus. Here we document a shifting landscape of risk for human exposure to medically important ticks and point to areas of re-emergence where enhanced vector surveillance and control may be warranted.
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Affiliation(s)
- Rebecca J. Eisen
- Division of Vector-Borne Diseases, NCEZID/CDC, 3156 Rampart Rd., Fort Collins, CO 80522
| | - Lars Eisen
- Division of Vector-Borne Diseases, NCEZID/CDC, 3156 Rampart Rd., Fort Collins, CO 80522
| | - Charles B. Beard
- Division of Vector-Borne Diseases, NCEZID/CDC, 3156 Rampart Rd., Fort Collins, CO 80522
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Harmon JR, Scott MC, Baker EM, Jones CJ, Hickling GJ. Molecular identification of Ehrlichia species and host bloodmeal source in Amblyomma americanum L. from two locations in Tennessee, United States. Ticks Tick Borne Dis 2015; 6:246-52. [PMID: 25682494 DOI: 10.1016/j.ttbdis.2015.01.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Revised: 01/12/2015] [Accepted: 01/15/2015] [Indexed: 11/26/2022]
Abstract
The current status of tick-borne diseases in the southeastern United States is challenging to define due to emerging pathogens, uncertain tick/host relationships, and changing disease case definitions. A golf-oriented retirement community on the Cumberland Plateau in Tennessee experienced an ehrlichiosis outbreak in 1993, prompting efforts to reduce the local tick population using '4-Poster' acaricide devices targeting white-tailed deer (Odocoileus virginianus). In 2009, the prevalence of Ehrlichia spp. in questing ticks was surveyed in the area and compared to a Tennessee state park where acaricide had not been applied. The range of wildlife hosts that immature Amblyomma americanum fed upon and the role that these hosts may play in pathogen dynamics were investigated using a reverse line blot (RLB) bloodmeal analysis technique. Amblyomma americanum was by far the most common tick species in both study areas (>99% of ticks collected). Of 303 adult and nymphal A. americanum tested at the retirement community, six were positive for Ehrlichia chaffeensis (2.0%), 16 were positive for E. ewingii (5.3%), and six were positive for Panola Mountain Ehrlichia (2.0%). This is the first confirmation of Panola Mountain Ehrlichia in A. americanum from the state of Tennessee. The 9.3% prevalence of Ehrlichia spp. in ticks from the retirement community was similar to that detected at the state park site (5.5%), suggesting that the 4-Poster treatment had not been sufficient to reduce Ehrlichia spp. cycling in the tick population. At both study sites, A. americanum fed on a wide range of mammal and bird species, with a minority of detectable bloodmeals coming from deer. Of the Ehrlichia-infected nymphs with positive bloodmeal identification, none fed on deer, indicating that multiple vertebrate species are contributing to sylvatic maintenance of Ehrlichia spp. at these sites. This highlights the difficulty of attempting to reduce the risk of tick-borne disease through host-targeted interventions alone.
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Affiliation(s)
- Jessica R Harmon
- University of Tennessee Institute of Agriculture, Entomology and Plant Pathology Department, United States; University of Tennessee Institute of Agriculture, Center for Wildlife Health, United States.
| | - M Cathy Scott
- University of Tennessee Institute of Agriculture, Center for Wildlife Health, United States
| | - Ellen M Baker
- University of Tennessee Institute of Agriculture, Center for Wildlife Health, United States
| | - Carl J Jones
- University of Tennessee Institute of Agriculture, Entomology and Plant Pathology Department, United States
| | - Graham J Hickling
- University of Tennessee Institute of Agriculture, Center for Wildlife Health, United States
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Mays SE, Hendricks BM, Paulsen DJ, Houston AE, Trout Fryxell RT. Prevalence of five tick-borne bacterial genera in adult Ixodes scapularis removed from white-tailed deer in western Tennessee. Parasit Vectors 2014; 7:473. [PMID: 25331818 PMCID: PMC4207311 DOI: 10.1186/s13071-014-0473-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2013] [Accepted: 10/02/2014] [Indexed: 11/10/2022] Open
Abstract
Background In the northeastern and midwestern regions of the United States Ixodes scapularis Say transmits the causal agents of anaplasmosis (Anaplasma phagocytophilum), babesiosis (Babesia microti), and borreliosis (Borrelia burgdorferi and B. miyamotoi). In the southeastern United States, none of those pathogens are considered endemic and two other tick-borne diseases (TBDs) (ehrlicihosis and rickettiosis) are more common. Our objective was to determine baseline presence and absence data for three non-endemic bacterial agents (Anaplasma, Borrelia and Babesia) and two commonly reported bacterial agents (Ehrlichia, and Rickettsia) in southern I. scapularis (n = 47) collected from 15 hunter-harvested white-tailed deer (Odocoileus virginianus) in western Tennessee. Findings Of the 47 ticks, 27 tested PCR positive for non-pathogenic Rickettsia species, two for Ehrlichia ewingii, one for Ehrlichia sp. “Panola Mountain”, and one for Anaplasma phagocytophilum variant 1 strain. None of these ticks were positive for Babesia or Borrelia (including B. burgdorferi). Conclusions Finding human pathogens in host-fed I. scapularis merits additional studies surveying pathogen prevalence in questing ticks. Collection of questing I. scapularis in their peak activity months should be undertaken to determine the overall encounter rates and relative risk of pathogenic Ehrlichia in southern I. scapularis. Ehrlichia sequences were homologous to previous human isolates, but neither Babesia nor B. burgdorferi were identified in these ticks. With the identification of pathogenic bacteria in this relatively small collection of I. scapularis from western Tennessee, the study of the absence of Lyme disease in the south should be refocused to evaluate the role of pathogenic Ehrlichia in southern I. scapularis.
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Affiliation(s)
- Sarah E Mays
- Department of Entomology and Plant Pathology, University of Tennessee, 370 Plant Biotechnology Building 2505 E J Chapman Drive, Knoxville, TN, USA.
| | - Brian M Hendricks
- Department of Entomology and Plant Pathology, University of Tennessee, 370 Plant Biotechnology Building 2505 E J Chapman Drive, Knoxville, TN, USA.
| | - David J Paulsen
- Department of Entomology and Plant Pathology, University of Tennessee, 370 Plant Biotechnology Building 2505 E J Chapman Drive, Knoxville, TN, USA.
| | - Allan E Houston
- Department of Forestry, Fisheries, and Wildlife, University of Tennessee, Tennessee and Ames Plantation, Grand Junction, Knoxville, Tennessee, USA.
| | - Rebecca T Trout Fryxell
- Department of Entomology and Plant Pathology, University of Tennessee, 370 Plant Biotechnology Building 2505 E J Chapman Drive, Knoxville, TN, USA.
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