Ticks harbor and excrete chronic wasting disease prions

H. N. Inzalaco; F. Bravo-Risi; R. Morales; D. P. Walsh; D. J. Storm; J. A. Pedersen; Wendy Christine Turner; S. S. Lichtenbergh

doi:10.1038/s41598-023-34308-3

Ticks harbor and excrete chronic wasting disease prions

Scientific Reports

Wisconsin DNR

By: H. N. Inzalaco, F. Bravo-Risi, R. Morales, D. P. Walsh, D. J. Storm, J. A. Pedersen, Wendy Christine Turner, and S. S. Lichtenbergh

https://doi.org/10.1038/s41598-023-34308-3

Metrics

17

Crossref references

Web analytics dashboard Metrics definitions

Links

More information: Publisher Index Page (via DOI)
Open Access Version: Publisher Index Page
Download citation as: RIS | Dublin Core

Abstract

Chronic wasting disease (CWD) is a fatal neurodegenerative disease caused by infectious prions (PrP^CWD) affecting cervids. Circulating PrP^CWD in blood may pose a risk for indirect transmission by way of hematophagous ectoparasites acting as mechanical vectors. Cervids can carry high tick infestations and exhibit allogrooming, a common tick defense strategy between conspecifics. Ingestion of ticks during allogrooming may expose naïve animals to CWD, if ticks harbor PrP^CWD. This study investigates whether ticks can harbor transmission-relevant quantities of PrP^CWD by combining experimental tick feeding trials and evaluation of ticks from free-ranging white-tailed deer (Odocoileus virginianus). Using the real-time quaking-induced conversion (RT-QuIC) assay, we show that black-legged ticks (Ixodes scapularis) fed PrP^CWD-spiked blood using artificial membranes ingest and excrete PrP^CWD. Combining results of RT-QuIC and protein misfolding cyclic amplification, we detected seeding activity from 6 of 15 (40%) pooled tick samples collected from wild CWD-infected white-tailed deer. Seeding activities in ticks were analogous to 10–1000 ng of CWD-positive retropharyngeal lymph node collected from deer upon which they were feeding. Estimates revealed a median infectious dose range of 0.3–42.4 per tick, suggesting that ticks can take up transmission-relevant amounts of PrP^CWD and may pose a CWD risk to cervids.

Study Area

Additional publication details
Publication type	Article
Publication Subtype	Journal Article
Title	Ticks harbor and excrete chronic wasting disease prions
Series title	Scientific Reports
DOI	10.1038/s41598-023-34308-3
Volume	13
Publication Date	May 15, 2023
Year Published	2023
Language	English
Publisher	Springer Nature
Contributing office(s)	Coop Res Unit Leetown
Description	7838, 13 p.
Country	United States
State	Wisconsin