MERS-CoV spillover at the camel-human interface
Abstract
Middle East respiratory syndrome coronavirus (MERS-CoV) is a zoonotic virus from camels causing significant mortality and morbidity in humans in the Arabian Peninsula. The epidemiology of the virus remains poorly understood, and while case-based and seroepidemiological studies have been employed extensively throughout the epidemic, viral sequence data have not been utilised to their full potential. Here we use existing MERS-CoV sequence data to explore its phylodynamics in two of its known major hosts, humans and camels. We employ structured coalescent models to show that long-term MERS-CoV evolution occurs exclusively in camels, whereas humans act as a transient, and ultimately terminal host. By analysing the distribution of human outbreak cluster sizes and zoonotic introduction times we show that human outbreaks in the Arabian peninsula are driven by seasonally varying zoonotic transfer of viruses from camels. Without heretofore unseen evolution of host tropism, MERS-CoV is unlikely to become endemic in humans.
Article and author information
Author details
Funding
National Institutes of Health (R35 GM119774-01)
- Trevor Bedford
Pew Charitable Trusts (Pew Biomedical Scholar)
- Trevor Bedford
European Commission (278433-PREDEMICS)
- Andrew Rambaut
Wellcome (206298/Z/17/Z)
- Andrew Rambaut
Fred Hutchinson Cancer Research Center (Mahan Postdoctoral Fellowship)
- Gytis Dudas
European Commission (725422-RESERVOIRDOCS)
- Andrew Rambaut
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Neil M Ferguson, Imperial College London, United Kingdom
Version history
- Received: August 14, 2017
- Accepted: December 19, 2017
- Accepted Manuscript published: January 16, 2018 (version 1)
- Version of Record published: January 22, 2018 (version 2)
- Version of Record updated: April 19, 2018 (version 3)
Copyright
© 2018, Dudas et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Further reading
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- Ecology
- Epidemiology and Global Health
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