DOI: 10.5061/dryad.tb2rbp00j
title: Data from: Prevalence and risk factors of Anaplasma infections in Eastern moose (Alces alces americana) and winter ticks (Dermacentor albipictus) in Maine, United States

description: Eastern moose (Alces alces americana) are heavily parasitized by winter
 ticks (Dermacentor albipictus), the dominant cause of increased calf
 mortality in the northeastern United States. Although much work has
 focused on the direct negative effects of winter tick on moose, it remains
 unknown whether diseases transmitted by ticks may also affect moose
 health, or pose a risk to other species. In this study, we explored the
 role that moose and winter ticks play in transmission of the tick-borne
 bacterial pathogen, Anaplasma, which causes mild to severe illness in
 humans and domestic animals. Our objectives were to (1) estimate the
 prevalence of Anaplasma spp. in moose and winter tick, (2) determine the
 phylogenetic placement of these strains with respect to those found in
 other hosts and vectors, and (3) explore risk factors of Anaplasma
 infection in moose. A total of 157 moose (142 calves, 15 adults) were
 captured in western (n = 83) and northern (n = 74) Maine in 2017 and 2018.
 We screened for Anaplasma spp. in moose whole blood samples using a
 genus-specific PCR assay targeting the 16S rRNA gene. We found that over
 half (54%) of the moose were infected with Anaplasma bacteria, with a
 greater proportion of moose harboring Anaplasma-infections in the western
 (67%) versus northern study areas (38%). Male moose also exhibited a
 higher prevalence than females (63% vs. 47%).  In contrast,
 Anaplasma prevalence in winter ticks was low (&lt;1%). Sequencing and
 phylogenetic analysis revealed that the single Anaplasma strain in moose
 was highly divergent from the strain in winter ticks, and most closely
 related to an uncharacterized North American cervid strain. We conclude
 that winter ticks are unlikely to play a significant role in Anaplasma
 transmission to moose, however high infection prevalence warrants further
 investigation into the impacts of the disease on moose health.
description: Blood samples were collected from moose during live captures,
 along with associated data on year, location in Maine (by Wildlife
 Management District, WMD), age (adult, calf), and sex (female, male).
 Winter ticks were collected from moose, and blacklegged ticks collected
 from the environment. Whole genomic DNA was extracted from biological
 samples from both moose and ticks, and used in genetic-based analyes for
 the detection of the bacteria of the genus Anaplasma. Tick samples were
 pooled for this analysis, with pool sizes varying between 1-5 ticks. When
 possible, sex (female, male, mixed) and life stage (adult, nymph) were
 idenified for each tick pool.
description: Detailed information on the metadata is provided within the data
 file.
description: This README file describes the data included in the Dryad submission for
 Elliott et al. 2021, "Prevalence and risk factors of Anaplasma
 infections in Eastern moose (Alces alces americanus) and winter ticks
 (Dermacentor albipictus) in Maine, United States". **Citation of the
 associated paper:** Elliott, J.A., C.C. Dickson, L. Kantar, M.R. O’Neal,
 A. Lichtenwalner, A. Bryant, W. Jakubas, P.J. Pekins, S.M. De
 Urioste-Stone, P.L. Kamath (2021). Prevalence and risk factors of
 Anaplasma infections in Eastern moose (Alces alces americana) and winter
 ticks (Dermacentor albipictus) in Maine, United States. Journal of
 Wildlife Diseases 57(4): 844-855. 1. Elliott_et_al_JWD_Data_Dryad.xlsx:
 Excel file with all data from both individual moose and ticks tested for
 Anaplasma, including identification numbers, year and region of
 collection, age, sex, infection status, and GenBank Accession numbers for
 the associated Anaplasma sequence data. Further explanation of metadata is
 provided with the file. **Version Changes:** **23-July-2025**: Corrected
 an error in one of the moose IFW_ID numbers. Moose IFW_ID number 18336
 (duplicate with GenBank Accession No. MW899041) was edited to IFW_ID
 number 18342.