Repeated introductions and intensive community transmission fueled a mumps virus outbreak in Washington State
- Fred Hutchinson Cancer Research Center, United States
- University of Washington, United States
- Washington State Department of Health, United States
- Arkansas Department of Health, United States
Abstract
In 2016/2017, Washington State experienced a mumps outbreak despite high childhood vaccination rates, with cases more frequently detected among school-aged children and members of the Marshallese community. We sequenced 166 mumps virus genomes collected in Washington and other US states, and traced mumps introductions and transmission within Washington. We uncover that mumps was introduced into Washington approximately 13 times, primarily from Arkansas, sparking multiple co-circulating transmission chains. Although age and vaccination status may have impacted transmission, our dataset could not quantify their precise effects. Instead, the outbreak in Washington was overwhelmingly sustained by transmission within the Marshallese community. Our findings underscore the utility of genomic data to clarify epidemiologic factors driving transmission, and pinpoint contact networks as critical for mumps transmission. These results imply that contact structures and historic disparities may leave populations at increased risk for respiratory virus disease even when a vaccine is effective and widely used.
Data availability
All code used to analyze data, input files for BEAST, and all code used to generate figures for this manuscript are publicly available at https://github.com/blab/mumps-wa-phylodynamics. Raw FASTQ files with human reads removed are available under SRA project number PRJNA641715. All protocols for generating sequence data as well as the consensus genomes are available at https://github.com/blab/mumps-seq. Consensus genomes have also been deposited to Genbank under accessions MT859507-MT859672.
Article and author information
Author details
Louise Hillier Moncla
Funding
National Science Foundation (DGE-1256082)
- Allison Black
Life Sciences Research Foundation
- Louise Hillier Moncla
National Institutes of Health (R35 GM119774-01)
- Trevor Bedford
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
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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Repeated introductions and intensive community transmission fueled a mumps virus outbreak in Washington State
eLife 10:e66448.
https://doi.org/10.7554/eLife.66448
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