A single mutation in Crimean-Congo hemorrhagic fever virus discovered in ticks impairs infectivity in human cells
- Centers for Disease Control and Prevention, United States
- Charité-Universitätsmedizin Berlin, Germany
- Charité - Universitätsmedizin Berlin, Germany
- Charité Universitätsmedizin, Germany
Abstract
Crimean-Congo Hemorrhagic Fever (CCHF) is the most widely distributed tick-borne viral infection in the world. Strikingly, reported mortality rates for CCHF are extremely variable, ranging from 5 to 80% (1). CCHF virus (CCHFV, Nairoviridae) exhibits extensive genomic sequence diversity across strains (2, 3). It is currently unknown if genomic diversity is a factor contributing to variation in its pathogenicity. We obtained complete genome sequences of CCHFV directly from the tick reservoir. These new strains belong to a solitary lineage named Europe 2 that is circumstantially reputed to be less pathogenic than the epidemic strains from Europe 1 lineage. We identified a single tick-specific amino acid variant in the viral glycoprotein region that dramatically reduces its fusion activity in human cells, providing evidence that a GPC variant, present in ticks, have severely impaired function in human cells.
Data availability
All sequencing data have been deposited in GB under accession codes MK299338, MK299339, MK299340, MK299341, MK299342, MK299343, MK299344, MK299345 and MK299346
Article and author information
Author details
Christina Spiropoulou
Funding
American Society for Microbiology
- Brian L Hua
Centers for Disease Control and Prevention
- Stuart T Nichol
- Christina Spiropoulou
- Éric Bergeron
Federal Ministry of Education and Research (01KI1716)
- Sandra Junglen
German Center for Infection Research (TTU 01.801)
- Christian Drosten
National Institutes of Health (R01AI109008)
- Éric Bergeron
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Sara L Sawyer, University of Colorado Boulder, United States
Version history
- Received: August 9, 2019
- Accepted: October 8, 2020
- Accepted Manuscript published: October 21, 2020 (version 1)
- Version of Record published: November 9, 2020 (version 2)
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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A single mutation in Crimean-Congo hemorrhagic fever virus discovered in ticks impairs infectivity in human cells
eLife 9:e50999.
https://doi.org/10.7554/eLife.50999
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