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ABSTRACT Mice in the genusPeromyscusare abundant and geographically widespread in North America, serving as reservoirs for zoonotic pathogens, includingBorrelia burgdorferi(B. burgdorferi), the causative agent of Lyme disease, transmitted byIxodes scapularisticks. While the white‐footed mouse (Peromyscus leucopus(P. leucopus)) is the primary reservoir in the United States, the deer mouse (P. maniculatus), an ecologically similar congener, rarely transmits the pathogen to biting ticks. Understanding the factors that allow these similar species to serve as a poor and competent reservoir is critical for understanding tick‐borne disease ecology and epidemiology, especially as climate change expands the habitats where ticks can transmit pathogens. Our study investigated immunological differences between these rodent species. Specifically, we compared the expression of six immune genes (i.e., TLR‐2, IFN‐γ, IL‐6, IL‐10, GATA‐3, TGF‐β) broadly involved in bacterial recognition, elimination, and/or pathology mitigation in ear biopsies collected by the National Ecological Observatory Network (NEON) as part of their routine surveillance. A principal components analysis indicated that immune gene expression in both species varied in two dimensions: TLR2, IFN‐γ, IL‐6, and IL‐10 (comprising PC1) and TGF‐β and GATA3 (comprising PC2) expression tended to covary within individuals. However, when we analyzed expression differences of each gene singly between species,P. maniculatusexpressed more TLR2, IL‐6, and IL‐10 but less IFN‐γ and GATA3 thanP. leucopus. This immune profile could partly explain whyP. leucopusis a better reservoir for bacterial pathogens such asB. burgdorferi.
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This content will become publicly available on August 13, 2026
Expanding range of Ixodes scapularis Say (Acari: Ixodidae) and Borrelia burgdorferi infection in North Carolina counties, 2018–2023
North Carolina (NC) has been experiencing a recent surge in human Lyme disease (LD) cases. Understanding the distribution of tick-borne diseases necessitates understanding the distribution of the ticks that transmit their causative pathogens. Unfortunately, in NC, knowledge on tick distribution is outdated. In this manuscript, we report the results of a state-wide entomologic survey conducted in 42 NC counties by flagging/dragging from spring 2018 to summer 2023.Ixodes scapularisnymphs and adults were screened forBorrelia burgdorferi(the causative agent of LD) and four other tick-borne bacterial pathogens (Anaplasma phagocytophilum,B. mayonii,B. miyamotoi, and Babesia microti) by the Centers for Disease Control and Prevention (CDC). Consistent with current data on human LD cases incidence and distribution, results of this study indicated a range expansion ofI. scapulariswith higher tick densities andB. burgdorferiinfection prevalence now occurring in the Blue Ridge Mountains province of western NC. Temporal analysis ofI. scapularispresence data indicated that this shift is fairly recent (about 10 years). Finally, in the Blue Ridge Mountains we detected a northeast-to-southwest gradient inI. scapularistick andB. burgdorferiinfection prevalence suggesting that this trend is driven by a spread of the northern cladeI. scapularisticks into NC from southwestern Virginia, along the Appalachian Mountains. Other pathogenic bacteria detected inI. scapularisticks includedB. miyamotoiandA. phagocytophilum, that were limited to the Blue Ridge Mountains.These results have important public health implications, including the need for enhanced tick surveillance, updated clinical awareness, and targeted public education in newly affected areas.
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- Award ID(s):
- 2322213
- PAR ID:
- 10641700
- Editor(s):
- Colunga-Salas, Pablo
- Publisher / Repository:
- The Public Library of Science (PLOS)
- Date Published:
- Journal Name:
- PLOS One
- Volume:
- 20
- Issue:
- 8
- ISSN:
- 1932-6203
- Page Range / eLocation ID:
- e0329511
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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