Publications

@article{nokey,

title = {Passerine birds as hosts for Ixodes ticks infected with Borrelia burgdorferi sensu stricto in southeastern Virginia},

author = {Cumbie, A.N. and E.L. Heller and Z.J. Bement and A. Phan and E.L. Walters and W.L. Hynes and H.D. Gaff},

url = {https://www.ericlwalters.org/Cumbie_et_al_2021.pdf, PDF link},

doi = {https://doi.org/10.1016/j.ttbdis.2021.101650},

year  = {2021},

date = {2021-01-12},

urldate = {2021-01-12},

journal = {Ticks and Tick-borne Diseases},

volume = {12},

issue = {2021},

pages = {101650},

abstract = {The ecology of vector-borne diseases in a region can be attributed to vector-host interactions. In the United States, tick-borne pathogens are the cause of the highest number of reported vector-borne diseases. In the mid-Atlantic region of the eastern United States, tick-borne diseases such as Lyme disease, have increased in incidence, with tick-host-pathogen interactions considered a contributing factor to this increase. Ticks become infected with pathogens after taking a blood meal from a systemically infected host or through a localized infection while co-feeding on a host with other infected ticks. The host not only plays a role in pathogen acquisition by the tick, but can also facilitate dispersal of the tick locally within a region or over greater distances into new geographical ranges outside of their historical distributional range. In this study conducted in southeastern Virginia (USA), we examined the interaction between both resident and migratory bird species and Ixodes ticks, the primary vectors of Borrelia burgdorferi sensu stricto (s.s.) the main causative agent of Lyme disease on the East coast of the United States. Over a two-year period (2012–2014), 1879 passerine birds were surveyed, with 255 Ixodes ticks tested for the presence of Borrelia spp. Eighty passerine birds (4.3 %) representing 17 bird species were parasitized by at least one Ixodes tick, but only three bird species were parasitized by Ixodes ticks that tested positive for B. burgdorferi s.s. Twenty Ixodes ticks (7.8 %) tested positive for B. burgdorferi s.s. with nearly all collected from resident bird species including the Carolina wren (Thryothorus ludovicianus) and brown thrasher (Toxostoma rufum). Given that millions of birds pass through southeastern Virginia during migration, even with the low number of Ixodes ticks parasitizing passerine birds and the low prevalence of B. burgdorferi s.s. found within Ixodes ticks collected, the sheer volume of passerine birds suggests they may play a role in the maintenance and dispersal of B. burgdorferi s.s. in southeastern Virginia.},

keywords = {peer-reviewed, ticks},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000497952700009,

title = {First report of Candidatus Rickettsia mendelii in Ixodes brunneus from  the United States},

author = {Alexandra N. Cumbie and Eric L. Walters and Holly D. Gaff and Wayne L. Hynes},

url = {https://www.ericlwalters.org/Cumbie_et_al_2020.pdf, PDF link},

doi = {10.1016/j.ttbdis.2019.101309},

issn = {1877-959X},

year  = {2020},

date = {2020-01-01},

urldate = {2020-01-01},

journal = {TICKS AND TICK-BORNE DISEASES},

volume = {11},

number = {1},

abstract = {Candidatus Rickettsia mendelii is a novel rickettsial species recently identified in Ixodes ricinus. In this study, Ixodes brunneus collected from wild birds (n = 77 ticks) or vegetation (n = 4 ticks) in southeastern Virginia were surveyed for rickettsial agents. Candidatus Rickettsia mendelii was confirmed in I. brunneus through sequencing of the gltA and 16S rRNA genes. This is the first report of this rickettsial species in Ixodes ticks in North America.},

keywords = {peer-reviewed, ticks},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000470930700022,

title = {Urbanization and tick parasitism in birds of coastal southeastern  Virginia},

author = {Erin L. Heller and Holly D. Gaff and R. Jory Brinkerhoff and Eric L. Walters},

url = {https://www.ericlwalters.org/Heller_et_al_2019.pdf, PDF link},

doi = {10.1002/jwmg.21646},

issn = {0022-541X},

year  = {2019},

date = {2019-05-01},

urldate = {2019-05-01},

journal = {JOURNAL OF WILDLIFE MANAGEMENT},

volume = {83},

number = {4},

pages = {975-984},

abstract = {One of North America's major avian migratory pathways occurs along a large anthropogenically modified coastal region of southeastern Virginia, USA. Because hundreds of avian species migrate along the east coast of North America, understanding factors affecting birds and their health is of ecological and conservation interest. Within southeastern Virginia, 14 tick species have been documented, all of which may serve as vectors of vertebrate pathogens. We tested 5 hypotheses to understand how varying levels of urbanization within an urban matrix of a coastal region affected avian parasitism rates. We sampled resident and migratory birds for ticks across an urbanization gradient at 5 permanent and 6 ad hoc sites from August 2012 to August 2014 and determined parasitism rates at the landscape and site scales. At the landscape scale, the proportion of birds parasitized by ticks was reduced at more urbanized sites. Urbanized sites were largely associated with higher water and impervious surfaces in the surrounding area, which may have prevented dispersal of ticks or hosts to isolated urban locations, and lower tree cover, which likely reduced tick survival because of decreased leaf litter. At the site scale, properties associated with being on or near the ground (i.e., foraging guild and age) were the best predictors of tick parasitism. These findings demonstrate that the effects of urbanization are neither uniform nor straightforward. In addition to affecting avian species composition, anthropogenic changes to the landscape are affecting the relationship between avian hosts and their parasites, a finding that has important implications for avian conservation efforts and management practices.},

keywords = {peer-reviewed, ticks},

pubstate = {published},

tppubtype = {article}

}

@article{WOS:000371908500021,

title = {New Records of Ixodes affinis (Acari: Ixodidae) Parasitizing Avian Hosts  in Southeastern Virginia},

author = {Erin L. Heller and Chelsea L. Wright and Robyn M. Nadolny and Wayne L. Hynes and Holly D. Gaff and Eric L. Walters},

url = {https://www.ericlwalters.org/Heller_et_al2016JME.pdf, PDF link},

doi = {10.1093/jme/tjv175},

issn = {0022-2585},

year  = {2016},

date = {2016-03-01},

urldate = {2016-03-01},

journal = {JOURNAL OF MEDICAL ENTOMOLOGY},

volume = {53},

number = {2},

pages = {441-445},

abstract = {Ixodes affinis Neumann (Acari: Ixodidae) is a hard-bodied tick species distributed throughout much of the southeastern United States. Although I. affinis does not parasitize humans, it is a competent vector of Borrelia burgdorferi sensu stricto, the causative-agent of Lyme disease, and thus contributes to the enzootic maintenance of this pathogen. This study presents evidence of I. affinis parasitizing five new host passerine species. During 2012–2014, 1,888 birds were captured and examined for ticks, and 18 immature I. affinis were collected from 12 birds—six Carolina Wrens ( Thyrothorus ludovicianus ); two Brown Thrashers ( Toxostoma rufum) ; and one American Robin ( Turdus migratorius) , Eastern Towhee ( Pipilo erythrophthalmus) , Northern Cardinal ( Cardinalis cardinalis ), and White-throated Sparrow ( Zonotrichia albicollis). Of 15 larvae and 3 nymphs collected, one nymph tested positive for B. burgdorferi DNA. I. affinis was found co-feeding on birds with immature Amblyomma americanum (L.) , Ixodes brunneus Koch , Ixodes dentatus Marx , Ixodes scapularis Say, and Haemaphysalis leporispalustris Packard . The results of this research provide a better understanding of I. affinis hosts and identify avian taxa that may play a role in the maintenance and dispersal of this tick species. },

keywords = {peer-reviewed, ticks},

pubstate = {published},

tppubtype = {article}

}