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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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Hantavirus in rodents in the United States: Temporal and spatial trends and report of new hosts
Abstract In North America, the rodent‐borne hantavirus pulmonary syndrome is predominantly caused by the Sin Nombre virus, typically associated with the deer mousePeromyscus maniculatus. Utilizing data from the National Ecological Observatory Network (NEON) hantavirus program, we assessed factors that may influence the spatial and temporal distribution of hantavirus in rodent populations across the United States. Between 2014 and 2019, the NEON hantavirus program conducted 104,379 small mammal captures and collected 14,004 blood samples from 49 species at 45 field sites. Our study identified 296 seropositive samples across 15 rodent species, including 8Peromyscusspecies. We describe six new species with hantavirus seropositive samples not previously reported as hantavirus hosts. The highest number of seropositive samples was obtained fromPe. maniculatus(n = 116; 2.9% seroprevalence), followed byPeromyscus leucopus(n = 96; 2.8%) andMicrotus pennsylvanicus(n = 33; 4.2%). Hantavirus seroprevalence showed an uneven spatial distribution, with the highest seroprevalence found in Virginia (7.8%, 99 seropositive samples), Colorado (5.7%,n = 37), and Texas (4.8%,n = 19). Hantavirus seropositive samples were obtained from 32 sites, 10 of which presented seropositive samples in species other thanPe. maniculatusorPe. leucopus. Seroprevalence was inconsistent across years but showed intra‐annual bimodal trends, and inPe. maniculatusandPe. leucopus, the number of captures correlated with seroprevalence in the following months. Seroprevalence was higher in adult males, with only one seropositive sample obtained from a juvenilePeromyscus truei. Higher body mass, presence of scrotal testes, and nonpregnant status were associated with higher seropositivity. The NEON dataset, derived from a multiyear and structured surveillance system, revealed the extensive distribution of hantavirus across broad taxonomic and environmental ranges. Future research should consider winter season surveillance and continued analyses of stored samples for a comprehensive spatiotemporal study of hantavirus circulation in wildlife. Global changes are expected to affect the dynamics of rodent populations by affecting their availability of resources and demography and, consequently, may modify transmission rates of rodent‐borne zoonotic pathogens such as hantavirus. This study can be considered a baseline to assess hantavirus patterns across host taxa, geographies, and seasons in the United States.
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- PAR ID:
- 10577653
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Ecosphere
- Volume:
- 16
- Issue:
- 3
- ISSN:
- 2150-8925
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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