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Williams SC, Linske MA. Late fall synthetic acaricide application is effective at reducing host-seeking adult and nymphal Ixodes scapularis (Ixodida: Ixodidae) abundances the following spring. J Med Entomol 2024:tjae044. [PMID: 38635041 DOI: 10.1093/jme/tjae044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 02/15/2024] [Accepted: 03/20/2024] [Indexed: 04/19/2024]
Abstract
Based on increases in reported cases of tick-borne illnesses, expanding ranges of native ticks, and repeated documentation of arrivals of nonnative tick species, there is a clear need for their effective management in the United States. Synthetic acaricides have proven efficacious in tick management, but real/perceived negative impacts to the environment and nontarget, beneficial insects must be addressed. We sought to determine whether late fall synthetic acaricide application, when most susceptible beneficial insects are presumably dormant or have migrated, could effectively manage host-seeking spring Ixodes scapularis Say abundances as compared to traditional spring application. We compared results of delivery of Demand CS (lambda-cyhalothrin) via truck-mounted high-pressure spray and powered backpack blower as well as delivery of granular Demand G to experimental control (water) in peridomestic habitats in fall 2021, spring 2022, and combined fall 2021/spring 2022. High-pressure fall delivery of Demand CS and backpack delivery of Demand G significantly reduced host-seeking adult I. scapularis abundances within-season and the following spring combined by 100% and 94%, respectively. No host-seeking nymphal I. scapularis were documented in spring after fall only, spring only, or fall and spring combined delivery of Demand CS via high-pressure or powered backpack blower. No adult I. scapularis were documented at any time posttreatment on locations that received high-pressure delivery of Demand CS. We conclude that high-pressure delivery of Demand CS in late fall successfully eliminated multiple stages of host-seeking I. scapularis through the following spring while likely limiting exposure of beneficial insects to synthetic pyrethroids.
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Affiliation(s)
- Scott C Williams
- Department of Environmental Science and Forestry, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT 06511, USA
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT 06511, USA
| | - Megan A Linske
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT 06511, USA
- Department of Entomology, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT 06511, USA
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2
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Linske MA, Williams SC. Evaluation of landscaping and vegetation management to suppress host-seeking Ixodes scapularis (Ixodida: Ixodidae) nymphs on residential properties in Connecticut, USA. Environ Entomol 2024; 53:268-276. [PMID: 38376061 DOI: 10.1093/ee/nvae007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 12/14/2023] [Accepted: 01/29/2024] [Indexed: 02/21/2024]
Abstract
Ticks and tick-borne diseases are of increasing concern across the United States, particularly in the Northeast. Ixodes scapularis Say (Ixodida: Ixodidae) remains the primary vector for the Lyme disease spirochete, Borrelia burgdorferi (Johnson, Schmid, Hyde, Steigerwalt, and Brenner). Prior studies established that I. scapularis can be found in greatest abundance in the 1-m forested ecotone surrounding the lawn edge in residential backyards. Our study was conducted on 42 properties in Guilford, CT, and sought to expand upon this premise by determining which key habitat features were associated with increased densities of host-seeking I. scapularis nymphs. We quantified nymphal abundances in 19 different habitat types that were posited to influence densities. We determined that nymphal I. scapularis densities were greatest in forested areas closest to lawn edges with leaf litter or understory vegetation present, as well as short lawns adjacent to woodland edges. Additionally, we determined that there were no significant declines in nymphal I. scapularis density where leaf litter was removed, lawns were left unmowed, or woodchip barriers were installed. Bird feeders and woodpiles were not associated with increased nymphal I. scapularis densities. However, areas adjacent to stone walls did have nearly 3 times the density of I. scapularis nymphs present compared with habitats without stone walls. The culmination of the results from this study can be utilized to create more targeted acaricide applications rather than broadcast spraying, as well as increase homeowner awareness for areas with heightened risk for exposure to nymphal I. scapularis, which are deemed the most epidemiologically important species and stage for pathogen transfer to humans.
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Affiliation(s)
- Megan A Linske
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
- Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
| | - Scott C Williams
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
- Department of Environmental Science and Forestry, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
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Holcomb KM, Khalil N, Cozens DW, Cantoni JL, Brackney DE, Linske MA, Williams SC, Molaei G, Eisen RJ. Comparison of acarological risk metrics derived from active and passive surveillance and their concordance with tick-borne disease incidence. Ticks Tick Borne Dis 2023; 14:102243. [PMID: 37611506 PMCID: PMC10885130 DOI: 10.1016/j.ttbdis.2023.102243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 07/19/2023] [Accepted: 08/15/2023] [Indexed: 08/25/2023]
Abstract
Tick-borne diseases continue to threaten human health across the United States. Both active and passive tick surveillance can complement human case surveillance, providing spatio-temporal information on when and where humans are at risk for encounters with ticks and tick-borne pathogens. However, little work has been done to assess the concordance of the acarological risk metrics from each surveillance method. We used data on Ixodes scapularis and its associated human pathogens from Connecticut (2019-2021) collected through active collections (drag sampling) or passive submissions from the public to compare county estimates of tick and pathogen presence, infection prevalence, and tick abundance by life stage. Between the surveillance strategies, we found complete agreement in estimates of tick and pathogen presence, high concordance in infection prevalence estimates for Anaplasma phagocytophilum, Borrelia burgdorferi sensu stricto, and Babesia microti, but no consistent relationships between actively and passively derived estimates of tick abundance or abundance of infected ticks by life stage. We also compared nymphal metrics (i.e., pathogen prevalence in nymphs, nymphal abundance, and abundance of infected nymphs) with reported incidence of Lyme disease, anaplasmosis, and babesiosis, but did not find any consistent relationships with any of these metrics. The small spatial and temporal scale for which we had consistently collected active and passive data limited our ability to find significant relationships. Findings are likely to differ if examined across a broader spatial or temporal coverage with greater variation in acarological and epidemiological outcomes. Our results indicate similar outcomes between some actively and passively derived tick surveillance metrics (tick and pathogen presence, pathogen prevalence), but comparisons were variable for abundance estimates.
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Affiliation(s)
- Karen M Holcomb
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, United States.
| | - Noelle Khalil
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT, United States
| | - Duncan W Cozens
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT, United States
| | - Jamie L Cantoni
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT, United States
| | - Doug E Brackney
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT, United States
| | - Megan A Linske
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT, United States
| | - Scott C Williams
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT, United States
| | - Goudarz Molaei
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT, United States; Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT, United States
| | - Rebecca J Eisen
- Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, United States
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Earnest R, Hahn AM, Feriancek NM, Brandt M, Filler RB, Zhao Z, Breban MI, Vogels CBF, Chen NFG, Koch RT, Porzucek AJ, Sodeinde A, Garbiel A, Keanna C, Litwak H, Stuber HR, Cantoni JL, Pitzer VE, Olarte Castillo XA, Goodman LB, Wilen CB, Linske MA, Williams SC, Grubaugh ND. Survey of white-footed mice in Connecticut, USA reveals low SARS-CoV-2 seroprevalence and infection with divergent betacoronaviruses. bioRxiv 2023:2023.09.22.559030. [PMID: 37808797 PMCID: PMC10557615 DOI: 10.1101/2023.09.22.559030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Diverse mammalian species display susceptibility to and infection with SARS-CoV-2. Potential SARS-CoV-2 spillback into rodents is understudied despite their host role for numerous zoonoses and human proximity. We assessed exposure and infection among white-footed mice (Peromyscus leucopus) in Connecticut, USA. We observed 1% (6/540) wild-type neutralizing antibody seroprevalence among 2020-2022 residential mice with no cross-neutralization of variants. We detected no SARS-CoV-2 infections via RT-qPCR, but identified non-SARS-CoV-2 betacoronavirus infections via pan-coronavirus PCR among 1% (5/468) of residential mice. Sequencing revealed two divergent betacoronaviruses, preliminarily named Peromyscus coronavirus-1 and -2. Both belong to the Betacoronavirus 1 species and are ~90% identical to the closest known relative, Porcine hemagglutinating encephalomyelitis virus. Low SARS-CoV-2 seroprevalence suggests white-footed mice may not be sufficiently susceptible or exposed to SARS-CoV-2 to present a long-term human health risk. However, the discovery of divergent, non-SARS-CoV-2 betacoronaviruses expands the diversity of known rodent coronaviruses and further investigation is required to understand their transmission extent.
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Affiliation(s)
- Rebecca Earnest
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA
| | - Anne M Hahn
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA
| | - Nicole M Feriancek
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA
| | - Matthew Brandt
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA
| | - Renata B Filler
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT 06520, USA
- Department of Immunobiology, Yale School of Medicine, New Haven, CT 06520, USA
| | - Zhe Zhao
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT 06520, USA
- Department of Immunobiology, Yale School of Medicine, New Haven, CT 06520, USA
| | - Mallery I Breban
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA
| | - Chantal B F Vogels
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA
| | - Nicholas F G Chen
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA
| | - Robert T Koch
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA
| | - Abbey J Porzucek
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA
| | - Afeez Sodeinde
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA
| | - Alexa Garbiel
- Department of Environmental Science and Forestry, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
| | - Claire Keanna
- Department of Environmental Science and Forestry, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
| | - Hannah Litwak
- Department of Environmental Science and Forestry, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
| | - Heidi R Stuber
- Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
| | - Jamie L Cantoni
- Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
| | - Virginia E Pitzer
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA
| | - Ximena A Olarte Castillo
- Department of Microbiology and Immunology, Cornell University College of Veterinary Medicine, Ithaca, NY 14853
| | - Laura B Goodman
- Department of Public & Ecosystem Health, Cornell University College of Veterinary Medicine, Ithaca, NY 14853
| | - Craig B Wilen
- Department of Laboratory Medicine, Yale School of Medicine, New Haven, CT 06520, USA
- Department of Immunobiology, Yale School of Medicine, New Haven, CT 06520, USA
| | - Megan A Linske
- Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
| | - Scott C Williams
- Department of Environmental Science and Forestry, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
| | - Nathan D Grubaugh
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06510, USA
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Williams SC, Linske MA, DeNicola AJ, DeNicola VL, Boulanger JR. Experimental oral delivery of the systemic acaricide moxidectin to free-ranging white-tailed deer (Artiodactyla: Cervidae) parasitized by Amblyomma americanum (Ixodida: Ixodidae). J Med Entomol 2023:7174277. [PMID: 37208791 DOI: 10.1093/jme/tjad056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 04/20/2023] [Accepted: 05/03/2023] [Indexed: 05/21/2023]
Abstract
Orally delivered, host-targeted, systemic acaricide treatment has potential to be an effective areawide tick abatement strategy. Past efforts using ivermectin for livestock were reported effective at controlling both Amblyomma americanum (L.) and Ixodes scapularis Say on Odocoileus virginianus (Zimmermann). However, the labeled 48-day withdrawal period for human consumption largely prevented utilization of this strategy targeting I. scapularis in autumn, when peak adult host-seeking activity coincides with regulated white-tailed deer hunting seasons. The modern-day compound moxidectin is the active ingredient in the pour-on formulation Cydectin (5 mg moxidectin/ml; Bayer Healthcare LLC), with a labeled 0-day withdrawal period for human consumption of treated cattle. We sought to re-examine the systemic acaricide approach for tick management by determining if we could successfully deliver Cydectin to free-ranging white-tailed deer. Over 2 yr in late spring/early summer, coinciding with adult and nymphal A. americanum activity, we fed Cydectin-coated corn to free-ranging white-tailed deer in coastal Connecticut. Through serum analysis, we documented moxidectin levels at or above those previously reported effective for control of ectoparasites (5-8 ppb for moxidectin and ivermectin) in 24 of 29 white-tailed deer captured (83%) while exposed to treated corn. While we did not document differences in burdens of parasitizing A. americanum based on moxidectin sera levels, we did document fewer engorged specimens on deer with increased sera levels. The systemic use of moxidectin for tick management in critical reproductive hosts has the potential to be effective in an areawide capacity while also permitting human consumption of treated venison.
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Affiliation(s)
- Scott C Williams
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT 06511, USA
- Department of Environmental Science and Forestry, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT 06511, USA
| | - Megan A Linske
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT 06511, USA
- Department of Entomology, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT 06511, USA
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Williams SC, Linske MA, Stafford KC. Orally delivered fipronil-laced bait reduces juvenile blacklegged tick (Ixodes scapularis) burdens on wild white-footed mice (Peromyscus leucopus). Ticks Tick Borne Dis 2023; 14:102189. [PMID: 37156086 DOI: 10.1016/j.ttbdis.2023.102189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 04/11/2023] [Accepted: 04/12/2023] [Indexed: 05/10/2023]
Abstract
While the topical acaricidal treatment of rodent pathogen reservoirs has been readily explored over the past several decades, oral systemic acaricidal treatment is only recently gaining traction as an alternative approach to the management of ticks and tick-borne pathogens. Recent laboratory tests have shown promise in the effectiveness of this systemic strategy against the blacklegged tick (Ixodes scapularis) and a Canadian field evaluation was recently published, but no recent field data from the United States yet exist. With this research, we sought to field deploy a commercially available fipronil-laced bait (Kaput® Flea Control Bait, Scimetrics LLC., Wellington, CO, USA; 0.005% fipronil; Environmental Protection Agency Reg. No. 72500-28), in an alternate use targeting white-footed mice (Peromyscus leucopus) to determine bait acceptance and potential impacts to juvenile I. scapularis burdens. Bait was readily accepted by wild P. leucopus and other rodent reservoirs. An ad libitum distribution strategy as well as placing smaller volumes of fipronil-laced bait within individual Sherman traps both resulted in significant reductions (57-94%) in juvenile I. scapularis burdens as compared to control over two years. The oral delivery of systemic acaricides shows promise in reduction of I. scapularis burdens on P. leucopus and should be further explored to determine effectiveness on host-seeking tick abundances, associated pathogen infection, and potentially incorporated into integrated tick management programs.
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Affiliation(s)
- Scott C Williams
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT 06511, USA; Department of Environmental Science and Forestry, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT 06511, USA.
| | - Megan A Linske
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT 06511, USA; Department of Entomology, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT 06511, USA.
| | - Kirby C Stafford
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT 06511, USA; Department of Entomology, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT 06511, USA.
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Linske MA, Williams SC, Stafford KC, Li AY. Integrated Tick Management in Guilford, CT: Fipronil-Based Rodent-Targeted Bait Box Deployment Configuration and Peromyscus leucopus (Rodentia: Cricetidae) Abundance Drive Reduction in Tick Burdens. J Med Entomol 2022; 59:591-597. [PMID: 34908136 DOI: 10.1093/jme/tjab200] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Indexed: 06/14/2023]
Abstract
Integrated tick management (ITM) is a comprehensive strategy used to reduce presence of ticks and their associated pathogens. Such strategies typically employ a combination of host and non-host targeted treatments which often include fipronil-based, rodent-targeted bait boxes. Bait boxes target small-bodied rodents, specifically white-footed mice (Peromyscus leucopus Rafinesque) that not only play a crucial role in the blacklegged tick (Ixodes scapularis Say (Ixodida: Ixodidae)) life cycle, but also in the transmission of numerous pathogens, primarily Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner (Spirochaetales: Spirochaetaceae), the causal agent of Lyme disease. This study aimed to determine the effect of bait box deployment configuration on tick burden reduction while also further exploring bait consumption and P. leucopus abundances as measures of bait box usage and effectiveness. Boxes were deployed on nine properties within each of six neighborhoods (n = 54) in two different configurations: grid and perimeter. Multiple factors were analyzed as potential predictors for reduction in tick burdens using a backward stepwise selection procedure. Results confirmed the perimeter configuration was a more effective deployment strategy. In addition, overall P. leucopus abundance was a significant predictor of tick burden reduction while bait consumption was not. These findings not only further support the recommended perimeter deployment configuration but provide insight into effective utilization in areas of high P. leucopus abundance. The identification of this significant relationship, in addition to configuration, can be utilized by vector control professionals and homeowners to make informed decisions on bait box placement to make sustained impacts on the I. scapularis vector and associated pathogens within an ITM framework.
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Affiliation(s)
- 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,USA
- Department of Entomology, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT, 06504, USA
| | - 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,USA
- Department of Forestry and Horticulture, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT, 06504, USA
| | - 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,USA
- Department of Entomology, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT, 06504, USA
| | - Andrew Y Li
- United States Department of Agriculture, Agricultural Research Service, Invasive Insect Biocontrol & Behavior Laboratory, BARC-West, Building 007, 10300, Baltimore Avenue, Beltsville, MD, 20705, USA
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Williams SC, van Oosterwijk JG, Linske MA, Zatechka S, Richer LM, Przybyszewski C, Wikel SK, Stafford KC. Administration of an Orally Delivered Substrate Targeting a Mammalian Zoonotic Pathogen Reservoir Population: Novel Application and Biomarker Analysis. Vector Borne Zoonotic Dis 2020; 20:603-612. [PMID: 32213011 DOI: 10.1089/vbz.2019.2612] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Reservoir-targeted vaccines (RTVs) have the potential to be effective at breaking the transmission cycle of many tick-borne pathogens including, but not limited to, Borrelia burgdorferi, B. miyamotoi, B. mayonii, Babesia microti, and Anaplasma phagocytophilum. To determine what proportion of a wild reservoir species we could effectively target, we distributed an experimental non-RTV Rhodamine B (RhB)-coated pellet formulation devoid of nutrient supplementation using bait boxes with ad libitum access, in battery-operated time-release bait stations, and by hand broadcast. Regardless of distribution method, a total of 208 of 242 (86%) white-footed mouse (Peromyscus leucopus) captures were positive for RhB by either pelage staining or by detecting fluorescent expression in vibrissae under a microscope. In bait box locations, 91% of captured mice were RhB-positive, 89% in hand broadcast locations, and 80% in time-release station locations. Based on results, we are confident that the bait formulation was readily accepted regardless of distribution technique, reached a substantial proportion of the reservoir population, and provides an effective vehicle to deliver a range of RTVs to targeted, wild, pathogen reservoir populations.
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Affiliation(s)
- Scott C Williams
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
| | | | - Megan A Linske
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
| | | | | | | | - Stephen K Wikel
- U.S. Biologic, Inc., Memphis, Tennessee, USA.,Department of Medical Sciences, School of Medicine, Quinnipiac University, Hamden, Connecticut, USA
| | - Kirby C Stafford
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
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Stafford KC, Williams SC, van Oosterwijk JG, Linske MA, Zatechka S, Richer LM, Molaei G, Przybyszewski C, Wikel SK. Field evaluation of a novel oral reservoir-targeted vaccine against Borrelia burgdorferi utilizing an inactivated whole-cell bacterial antigen expression vehicle. Exp Appl Acarol 2020; 80:257-268. [PMID: 31898760 DOI: 10.1007/s10493-019-00458-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Accepted: 12/24/2019] [Indexed: 06/10/2023]
Abstract
Blacklegged ticks (Ixodes scapularis) are the principal vector for Borrelia burgdorferi, among other infectious agents, in the northeastern, mid-Atlantic, and upper midwestern USA. White-footed mice (Peromyscus leucopus) are the primary and most competent reservoir host of B. burgdorferi in the Northeast. Live reservoir-targeted vaccines (RTVs) to limit enzootic transmission of B. burgdorferi were previously developed and successfully evaluated in laboratory and controlled field trials. A novel, inactivated RTV was developed to minimize regulatory and market challenges facing previous RTVs based on live bacterial or viral vehicles. Thirty-two residential properties in Redding, Connecticut, participated in a field trial of an orally delivered, inactivated RTV efficacy study (2015-2016). During the two-year vaccination period, a significant decrease in the percentage of B. burgdorferi-infected I. scapularis larvae parasitizing P. leucopus was observed, as was a significant reduction in the percentage of infected P. leucopus on RTV-treated properties when compared to control properties. This novel inactivated RTV was effective in reducing numbers of B. burgdorferi-infected I. scapularis and B. burgdorferi-infected P. leucopus on properties where it was distributed.
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Affiliation(s)
- Kirby C Stafford
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
| | - Scott C Williams
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA.
| | | | - Megan A Linske
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
| | | | | | - Goudarz Molaei
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
- Department of Epidemiology of Microbial Diseases, School of Public Health, Yale University, New Haven, CT, USA
| | | | - Stephen K Wikel
- U.S. Biologic, Inc., Memphis, TN, USA
- Department of Medical Sciences, School of Medicine, Quinnipiac University, Hamden, CT, USA
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11
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Little EAH, Williams SC, Stafford KC, Linske MA, Molaei G. Evaluating the effectiveness of an integrated tick management approach on multiple pathogen infection in Ixodes scapularis questing nymphs and larvae parasitizing white-footed mice. Exp Appl Acarol 2020; 80:127-136. [PMID: 31853763 DOI: 10.1007/s10493-019-00452-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 12/12/2019] [Indexed: 06/10/2023]
Abstract
We investigated the effectiveness of integrated tick management (ITM) approaches in reducing the burden of infection with Borrelia burgdorferi, Babesia microti, and Anaplasma phagocytophilum in Ixodes scapularis. We found a 52% reduction in encountering a questing nymph in the Metarhizium anisopliae (Met52) and fipronil rodent bait box treatment combination as well as a 51% reduction in the combined white-tailed deer (Odocoileus virginianus) removal, Met52, and fipronil rodent bait box treatment compared to the control treatment. The Met52 and fipronil rodent bait box treatment combination reduced the encounter potential with a questing nymph infected with any pathogen by 53%. Compared to the control treatment, the odds of collecting a parasitizing I. scapularis infected with any pathogen from a white-footed mouse (Peromyscus leucopus) was reduced by 90% in the combined deer removal, Met52, and fipronil rodent bait box treatment and by 93% in the Met52 and fipronil rodent bait box treatment combination. Our study highlights the utility of these ITM measures in reducing both the abundance of juvenile I. scapularis and infection with the aforementioned pathogens.
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Affiliation(s)
- Eliza A H Little
- Department of Entomology, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
- Center for Vector Biology & Zoonotic Diseases and Northeast Regional Center for Excellence in Vector-borne Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
| | - Scott C Williams
- Center for Vector Biology & Zoonotic Diseases and Northeast Regional Center for Excellence in Vector-borne Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
- Department of Forestry and Horticulture, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
| | - Kirby C Stafford
- Department of Entomology, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
- Center for Vector Biology & Zoonotic Diseases and Northeast Regional Center for Excellence in Vector-borne Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
| | - Megan A Linske
- Department of Entomology, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
- Center for Vector Biology & Zoonotic Diseases and Northeast Regional Center for Excellence in Vector-borne Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
| | - Goudarz Molaei
- Center for Vector Biology & Zoonotic Diseases and Northeast Regional Center for Excellence in Vector-borne Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA.
- Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA.
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, P.O. Box 208034, 60 College Street, New Haven, CT, 06520-8034, USA.
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12
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Linske MA, Williams SC, Stafford KC, Lubelczyk CB, Henderson EF, Welch M, Teel PD. Determining Effects of Winter Weather Conditions on Adult Amblyomma americanum (Acari: Ixodidae) Survival in Connecticut and Maine, USA. Insects 2019; 11:insects11010013. [PMID: 31877783 PMCID: PMC7023149 DOI: 10.3390/insects11010013] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 12/17/2019] [Accepted: 12/19/2019] [Indexed: 12/01/2022]
Abstract
The lone star tick (Amblyomma americanum L.) is native to the United States, with its primary range encompassing the Southeast and portions of the Midwest. It is an aggressive ectoparasite that actively seeks out hosts through detection of carbon dioxide and vibrations and can transfer ehrlichiosis-causing bacteria as well as a carbohydrate that causes alpha-gal syndrome (red meat allergy) in humans. It has become of increasing concern as its range has recently expanded into coastal regions of the Northeast. Historically, harsh northeastern winter weather conditions made these areas inhospitable for A. americanum survival, but a warming climate coupled with increased host availability seem to have facilitated their range expansion. We developed a study to observe the effects of weather conditions on adult A. americanum overwintering survival. The study was conducted over three years in Connecticut and Maine. Ground-level conditions were manipulated to determine the effects of differing combinations of natural insulative barriers (leaf litter and snow accumulation) on adult A. americanum survival. We determined that there was a significant difference in survival between the two states, between years in Maine, and between sexes within Connecticut. However, presence or absence of snow and/or leaf litter had no impact on survival. Overall, we found a positive correlation between mean hourly temperature and adult survival in Maine, where temperatures were consistently below freezing. The results of this study can be included in an adaptive, predictive analytic model to accommodate the expected fluctuations and range expansion of A. americanum that will most likely accompany an increase in temperatures throughout the Northeast.
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Affiliation(s)
- Megan A. Linske
- Department of Entomology, Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, P.O. Box 1106, New Haven, CT 06504, USA; (M.A.L.)
| | - Scott C. Williams
- Department of Forestry and Horticulture, Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, P.O. Box 1106, New Haven, CT 06504, USA
- Correspondence: ; Tel.: +1-(203)-974-8609; Fax: +1-(203)-974-8502
| | - Kirby C. Stafford
- Department of Entomology, Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, P.O. Box 1106, New Haven, CT 06504, USA; (M.A.L.)
| | - Charles B. Lubelczyk
- Vector-borne Disease Laboratory, Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074, USA; (C.B.L.); (E.F.H.); (M.W.)
| | - Elizabeth F. Henderson
- Vector-borne Disease Laboratory, Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074, USA; (C.B.L.); (E.F.H.); (M.W.)
| | - Margret Welch
- Vector-borne Disease Laboratory, Maine Medical Center Research Institute, 81 Research Drive, Scarborough, ME 04074, USA; (C.B.L.); (E.F.H.); (M.W.)
| | - Peter D. Teel
- Department of Entomology, Texas A&M University, TAMU 2475, College Station, TX 77843, USA;
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Linske MA, Williams SC, Ward JS, Stafford KC. Indirect Effects of Japanese Barberry Infestations on White-Footed Mice Exposure to Borrelia burgdorferi. Environ Entomol 2018; 47:795-802. [PMID: 29850912 DOI: 10.1093/ee/nvy079] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Indexed: 06/08/2023]
Abstract
Japanese barberry (Berberis thunbergii de Candolle; Ranunculales: Berberidaceae) is an exotic shrub that has invaded woodland understories in the northeastern United States. It forms dense thickets providing ideal structure and microclimate for questing blacklegged ticks (Ixodes scapularis Say; Acari: Ixodidae). While there have been studies on the favorable habitat barberry provides blacklegged ticks, little has been studied on the relationship between barberry, vectors (ticks), and reservoirs (white-footed mice; Peromyscus leucopus Rafinesque; Rodentia: Cricetidae); specifically, the influence Japanese barberry has on the abundance of blacklegged ticks and Borrelia burgdorferi infection (Johnson, Schmid, Hyde, Steigerwalt, and Brenner; Spirochaetales: Spirochaetaceae) in mice. We studied the impacts of barberry treatment over the course of 6 yr to determine influence on encounter abundance with white-footed mice, encounter abundance with B. burgdorferi-infected mice, and juvenile blacklegged ticks parasitizing mice. Results from our study suggest that while both white-footed mouse and B. burgdorferi-infected mouse encounters remained similar between barberry treatment areas, juvenile tick attachment to mice was significantly greater in intact barberry stands (X¯ = 4.4 ticks per mouse ± 0.23 SEM) compared with managed (X¯ = 2.8 ± 0.17; P < 0.001) or absent (X¯ = 2.2 ± 0.16; P < 0.001) stands. Results of this study indicated that management of barberry stands reduced contact opportunities between blacklegged ticks and white-footed mice. Continued efforts to manage Japanese barberry will not only allow for reestablishment of native plant species, but will also reduce the number of B. burgdorferi-infected blacklegged ticks on the landscape.
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Affiliation(s)
- Megan A Linske
- Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT
- Department of Natural Resources and the Environment, College of Agriculture, Health, and Natural Resources, University of Connecticut, Storrs, CT
| | - Scott C Williams
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT
| | - Jeffrey S Ward
- Department of Forestry and Horticulture, The Connecticut Agricultural Experiment Station, New Haven, CT
| | - Kirby C Stafford
- Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT
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14
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Williams SC, Little EAH, Stafford KC, Molaei G, Linske MA. Integrated control of juvenile Ixodes scapularis parasitizing Peromyscus leucopus in residential settings in Connecticut, United States. Ticks Tick Borne Dis 2018; 9:1310-1316. [PMID: 29859885 DOI: 10.1016/j.ttbdis.2018.05.014] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 05/17/2018] [Accepted: 05/26/2018] [Indexed: 10/14/2022]
Abstract
Lyme disease continues to be the most common vector-borne disease in the United States with an estimated 330,000 human cases annually. In the eastern United States, the blacklegged tick, Ixodes scapularis, is the primary vector of the Lyme disease spirochete, Borrelia burgdorferi, and the white-footed mouse, Peromyscus leucopus, is a primary reservoir host. In four residential neighborhoods in Connecticut over three years, we tested the effectiveness of different low-toxicity integrated tick management approaches to control larval and nymphal I. scapularis parasitizing P. leucopus. Combinations of white-tailed deer, Odocoileus virginianus, reduction, broadcast application of the entomopathogenic fungus Metarhizium anisopliae, and distribution of fipronil-based rodent-targeted bait boxes were evaluated against an experimental control. Deer reduction with no other intervention likely forced juvenile I. scapularis to obtain blood meals from available reservoir hosts, resulting in increased exposure of P. leucopus to B. burgdorferi compared to control sites. The M. anisopliae/bait box and the deer reduction/M. anisopliae/bait box treatment combinations resulted in 94% and 85% reductions in larvae parasitizing P. leucopus that tested positive for B. burgdorferi, respectively, compared to control. Deer reduction alone resulted in only a 3% reduction, likely because parasitizing juvenile I. scapularis were not targeted by bait box-delivered fipronil. Unless there is community support to reduce and maintain deer at very low densities (<5 deer/km2), it is clear that a combination of M. anisopliae/fipronil-based bait boxes offers an effective, localized, low-toxicity option for reducing I. scapularis parasitizing P. leucopus without complications from host switching.
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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, USA.
| | - Eliza A H Little
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT 06504, USA.
| | - 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, USA.
| | - Goudarz Molaei
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, P.O. Box 1106, 123 Huntington Street, New Haven, CT 06504, USA; Department of Epidemiology of Microbial Diseases, School of Public Health, Yale University, 60 College Street, P.O. Box 208034, New Haven, CT 06520-8034, USA.
| | - 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, USA.
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15
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Linske MA, Williams SC, Stafford KC, Ortega IM. Ixodes scapularis (Acari: Ixodidae) Reservoir Host Diversity and Abundance Impacts on Dilution of Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) in Residential and Woodland Habitats in Connecticut, United States. J Med Entomol 2018; 55:681-690. [PMID: 29340657 DOI: 10.1093/jme/tjx237] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Indexed: 06/07/2023]
Abstract
The dilution effect in the zoonotic disease transmission cycle theorizes that an increased diversity of host species will alter transmission dynamics, result in a decrease in pathogen prevalence, and potentially lower human disease incidence. The interrelationship of Borrelia burgdorferi (Johnson, Schmid, Hyde, Steigerwalt, and Brenner) (Spirochaetales: Spirochaetaceae), the etiological agent of Lyme disease (LD), and its primary vector, blacklegged ticks (Ixodes scapularis Say) (Acari: Ixodidae), is a commonly used example of the dilution effect, suggesting that an increased diversity of host species will be found in large, undisturbed forested tracts and lower diversity in fragmented forests. Given that Connecticut woodlands are mature with heavy upper canopies and generally poor habitat quality, we hypothesized there would be higher diversity of host species resulting in lower prevalence of B. burgdorferi in white-footed mice (Peromyscus leucopus Rafinesque) (Rodentia: Cricetidae) in forested residential areas. Using camera and live small mammal trapping techniques, we determined there was a greater richness of reservoir host species, significantly higher encounters with hosts, and significantly lower B. burgdorferi host-infection in residential areas as compared to large, intact forested stands. Furthermore, we determined that the driving factor of pathogen dilution was not host species diversity, but rather overall encounter abundance with alternative hosts, regardless of habitat type. Our study challenges major concepts of the dilution effect within the Connecticut landscape and calls for new managerial actions to address the current state of our woodlands and abundance of host species in the interest of both forest and public health.
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Affiliation(s)
- Megan A Linske
- Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT
- Department of Natural Resources and the Environment, College of Agriculture, Health, and Natural Resources, University of Connecticut, Storrs, CT
| | - Scott C Williams
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT
- Department of Forestry and Horticulture, The Connecticut Agricultural Experiment Station, New Haven, CT
| | - Kirby C Stafford
- Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT
| | - Isaac M Ortega
- Department of Natural Resources and the Environment, College of Agriculture, Health, and Natural Resources, University of Connecticut, Storrs, CT
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16
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Williams SC, Linske MA, Ward JS. Long-Term Effects of Berberis thunbergii (Ranunculales: Berberidaceae) Management on Ixodes scapularis (Acari: Ixodidae) Abundance and Borrelia burgdorferi (Spirochaetales: Spirochaetaceae) Prevalence in Connecticut, USA. Environ Entomol 2017; 46:1329-1338. [PMID: 29029041 DOI: 10.1093/ee/nvx146] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2017] [Indexed: 06/07/2023]
Abstract
Japanese barberry (Berberis thunbergii de Candolle; Ranunculales: Berberidaceae) is an exotic invasive shrub that escaped cultivation in the United States and is now permanently established in many eastern and midwestern states. This study examined the long-term impacts of Japanese barberry management on blacklegged tick (Ixodes scapularis Say; Acari: Ixodidae) abundances and associated prevalence of Borrelia burgdorferi (Johnson, Schmid, Hyde, Steigerwalt, and Brenner; Spirochaetales: Spirochaetaceae), the etiologic agent of Lyme disease. At six locations across Connecticut, adult I. scapularis were sampled for up to 10 yr. At each location, we sampled an area where barberry infestations were unmanipulated, adjacent areas where barberry was virtually nonexistent, and areas where barberry was managed utilizing a variety of techniques. Barberry management reduced B. burgdorferi-infected adult I. scapularis (BBIAIS) abundances (191/ha ± 64 SE) over 6 yr to statistically indifferent from that of no barberry areas (140/ha ± 47 SE; P = 0.080) and significantly less than intact barberry stands (458/ha ± 80 SE; P = 0.026). Over 9 yr, BBIAIS abundances in managed barberry remained lower than intact barberry stands (P = 0.037), but increased to be significantly greater than no barberry areas (P = 0.007) as cover increased over time. Longer-term data further document that Japanese barberry infestations are favorable habitat for I. scapularis. Control of Japanese barberry and other invasives should be at least on a 5-yr rotation to maintain low levels of invasive cover and eliminate humidity refugia to expose juvenile I. scapularis to more hostile environmental conditions in the interest of public health.
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Affiliation(s)
- Scott C Williams
- Department of Forestry and Horticulture, The Connecticut Agricultural Experiment Station, New Haven, CT 06504
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT 06504
| | - Megan A Linske
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT 06504
- Department of Natural Resources and the Environment, College of Agriculture, Health, and Natural Resources, University of Connecticut, Storrs, CT 06269-4087
| | - Jeffrey S Ward
- Department of Forestry and Horticulture, The Connecticut Agricultural Experiment Station, New Haven, CT 06504
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Williams SC, Stafford KC, Molaei G, Linske MA. Integrated Control of Nymphal Ixodes scapularis: Effectiveness of White-Tailed Deer Reduction, the Entomopathogenic Fungus Metarhizium anisopliae, and Fipronil-Based Rodent Bait Boxes. Vector Borne Zoonotic Dis 2017; 18:55-64. [PMID: 29173127 DOI: 10.1089/vbz.2017.2146] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Pathogens transmitted by ticks are the leading cause of arthropod-associated human diseases in the United States and managing the risk of exposure to potentially infected ticks is of vital public health importance. A 3-year integrated tick management program to control blacklegged ticks, Ixodes scapularis, the primary vector for the pathogenic agents of Lyme disease, human anaplasmosis, and babesiosis, was implemented in the town of Redding in southwestern Connecticut beginning in 2013. Combinations of white-tailed deer, Odocoileus virginianus, reduction, area application of the entomopathogenic fungus Metarhizium anisopliae, and fipronil-based rodent bait boxes were evaluated for their ability to reduce nymphal I. scapularis over 3 years. Interference from local hunters prevented sufficient, sustained deer removal previously reported to negatively impact I. scapularis abundances (i.e., <5 deer/km2). The combination of fipronil-based bait boxes and broadcast application of M. anisopliae had the most impact of any treatment combination; questing nymphs were reduced 78-95% within each year and Borrelia burgdorferi-infected questing nymphal I. scapularis encounter potential was reduced by 66% as compared with no treatment in the third year of the study. A combination of the broadcast application of M. anisopliae and small rodent-targeted fipronil-based bait boxes is an effective low-toxicity integrated approach that significantly reduced encounters with B. burgdorferi-infected questing nymphal I. scapularis on individual properties.
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Affiliation(s)
- Scott C Williams
- 1 Center for Vector Biology & Zoonotic Diseases , The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Kirby C Stafford
- 1 Center for Vector Biology & Zoonotic Diseases , The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Goudarz Molaei
- 1 Center for Vector Biology & Zoonotic Diseases , The Connecticut Agricultural Experiment Station, New Haven, Connecticut.,2 Department of Epidemiology of Microbial Diseases, School of Public Health, Yale University , New Haven, Connecticut
| | - Megan A Linske
- 1 Center for Vector Biology & Zoonotic Diseases , The Connecticut Agricultural Experiment Station, New Haven, Connecticut
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