Adapted from a news release by the USDA Forest Service.
Fire camps emerge overnight to house, feed, supply and organize personnel working 16-hour days to contain wildfires. With firefighters from all over the country sharing close quarters, these high-density living and working conditions can create the ideal environment for the spread of respiratory illnesses like COVID-19.
Newly published research in Scientific Reports from researchers with Colorado State University and the USDA explores potential health and workforce capacity impacts by modeling the movement of wildfire suppression personnel across the country over an entire fire season and the potential for cascading outbreaks across wildfire incidents. This research demonstrates that vaccines and social distancing are effective at limiting the spread of COVID-19 within and between wildland fire incidents, as well as reducing its impact on the wildland firefighting workforce.
A team effort
In March 2020, the USDA Forest Service Rocky Mountain Research Station assembled a team of risk management experts to help with pandemic response. While they quickly recognized that the conditions in fire camps could lead to the spread of COVID-19, no one knew what the level of risk really looked like or how effectively it could be mitigated.
The problem was complex, requiring not only expertise in how disease spreads, but also knowledge of how fire response works on the ground. To tackle it, Rocky Mountain Research Station risk management scientists Erin Belval and Matt Thompson joined forces with CSU’s epidemiological modeling and coding experts Jude Bayham and Jacob Dilliott, along with Andrea Buchwald from the University of Colorado’s School of Public Health, to create the COVID-19 Fire Modeling Team.
“The COVID-19 Fire Modeling Team formed early in the pandemic to provide the firefighting community key insights into what managing a pandemic during fire season could possibly entail,” said Bayham, the study’s co-author and an assistant professor in the Department of Agricultural and Resource Economics at CSU. “Since then, we’ve refined our model to represent different scenarios while accounting for things like uneven vaccination rates among firefighters.”
The team took a unique approach that paired historical data on wildland fire assignments with an epidemiological model, said Belval, a research forester with the Rocky Mountain Research Station.
“Getting all the right people together at the right time allowed us to build a complex model that we could use immediately in 2021 to examine the impact of uncertain factors like vaccination rates on the wildland fire workforce,” she said.
Modeling the spread of COVID-19
For their latest publication, the team modeled how COVID-19 might spread through and between incidents over the course of a fire year and how this spread could impact the capacity of the wildland fire response system.
Scenarios represented a variation in when and where fires occur, levels of vaccination, and compliance with social distancing measures. Results showed that a high vaccination rate – and the policy that vaccinated individuals do not need to quarantine after exposure – results in significantly fewer worker days missed and less lost pay.
The study also showed that the number of COVID-19 infections acquired off-fire is substantially higher than those acquired on-fire, highlighting the importance of communication around behaviors outside the fire environment. While data around COVID-19 infections in firefighters is sparse, the team was also able to access 2021 data from the Incident COVID-19 Tracking System to provide context for their model results.
“This research combined expertise, data and modeling methods to provide insights about how COVID-19 could impact interagency fire fighting capacity,” said Monica Lear, Director of the USDA Forest Service Rocky Mountain Research Station. “This collaborative effort resulted in practical recommendations for creating a more resilient, safe and responsive workforce.”
It also builds on work conducted during the 2020 fire year, when the team developed a scenario analysis that explored how the virus could spread in fire camps and a COVID-19 Fire Incident Specific Risk Assessment Tool designed to help understand risks to firefighter health at the individual incident level.
While not intended to forecast outbreaks in future fire seasons, this research can set the foundation for future modeling efforts focused on mitigating the spread of disease at wildland fire incidents, bolstering system capacity to respond to fires, and protecting the health of firefighting personnel.