Model predicts a large, long-duration fire could cause 1 to 13 firefighter fatalities from COVID-19

August 11, 2020 | 1 p.m. MDT

Lolo Peak Fire
Lolo Peak Fire at 6:25 p.m. MDT August 19, 2017 as seen from the Missoula area. Photo by Dick Mangan.

Researchers developed a COVID-19 epidemic model to highlight the risks posed by the disease during wildland fire incidents. A paper published August 1, 2020 details how  they started with actual mobilization data from the Resource Ordering and Status System (ROSS) for three 2017 wildfires that had different characteristics — the Highline Fire, which burned for much of the summer but the personnel peaked early in the effort; the Lolo Peak Fire, which spanned July through September and had a relatively symmetric mobilization and demobilization phase; and the Tank Hollow Fire, which was shorter than the other two, and had fewer personnel throughout the incident.

 firefighters wildfire COVID-19
Figure 1. Total personnel assigned and expected to be at the fire camp (e.g., non-aerial resources) for three large incidents over time; data are from the Resource Ordering and Status System. From the study.

The variables that were modeled included the number of infected persons arriving at a fire, the rate of secondary infections caused by an infected person, infection fatality rate, and the number of people assigned to the fire each day.

There are also many other variables that are difficult or impossible to account for, such as social distancing at the incident, protocols followed by personnel in the weeks before the assignment, how much time they spend at fire camp, mode of travel to and during the incident, wearing of masks, testing before and during the incident, working remotely, and others.

Below is an excerpt from the study:


“Models are, by definition, an abstraction of reality and are subject to the accuracy of the parameters. Wildfires and the COVID-19 pandemic are each complex dynamic phenomenon, and the combination of the two produces great uncertainty. Therefore, we stress the limits of our model and highlight the qualitative results of the analysis rather than the estimated numbers.

“In this study, we focused on two sources of case growth on an incident. The first is the introduction of infection by personnel arriving on an incident. As the fire grows and the incident becomes more complex, resource orders will be filled by available personnel, some of whom may come from other counties or states. Given the variation in the COVID-19 prevalence around the country at any given point in time, the firefighters from different areas will introduce variable risk to the camp. While current policies require or request symptomatic individuals to report their conditions and inform supervisors, evidence suggests that many infected people may experience very mild symptoms. These asymptomatic individuals may remain infectious for weeks, perhaps posing the greatest risk of infection through a camp. The combination of exposure risk posed by the high turnover of personnel coming from a large number of places in concert with the exposure risk due to non-quarantined infectious individuals highlights the potential merits of developing testing strategies for early identification, which could include testing asymptomatic individuals without known or suspected exposure. The utility of such testing strategies is conditioned by the availability, timeliness, and reliability of viral tests, and the optimal testing strategy design could be the subject of future research.

“The second source of case growth on an incident that we examined was the spread among personnel while assigned to the fire. In the event that personnel arrive at an incident exposed or infected, their level of interaction with others will determine the rate of transmission within the camp. The rate of transmission will depend on the level of interaction between the personnel at the incident and the nature of those interactions. Under normal circumstances, personnel may gather in large groups, for example, for briefings or meals. These interactions are similar to potentially infectious interactions in the general public that public health agencies have deemed ill-advised. Some of these interactions could be made less risky using current social distancing and mitigation recommendations; for example, masks appear to provide a barrier to the spread of SARS-CoV-2. Recognizing that a range of mitigations is already being planned or put into place by incident management personnel, these analyses provide a proxy for a business-as-usual baseline as a point of comparison.

“We studied two types of interventions corresponding to the two types of source growth identified above: the screening of personnel arriving at the incident to address the case growth by the entry of the virus and the spread from non-quarantined infectious individuals, and social distancing measures within the fire camp to address the case growth from the spread among individuals in the camp. While both interventions mitigate transmission and lead to fewer cases, screening measures are relatively more effective on shorter incidents with a frequent resource turn over. In contrast, social distancing measures are relatively more effective on prolonged campaigns where most of the cases are due to transmission within the community.”

infected individuals firefighters wildfire COVID-19
Figure 4. Total number of infected individuals over the duration of each incident under the low (0.1%), medium (1%), and high (5%) entry rates of infected individuals. Note that the vertical axis is log scaled. All simulations assume R0 of 2.68. From the study.

The researchers found that a large, long-duration fire with a hundreds of personnel is likely to have more infected individuals and fatalities than shorter-duration incidents with fewer individuals. Under COVID-19 conditions, a fire like the 2017 Lolo Peak Fire south of Missoula could have, according to their modeling, from less than 1 or up to 13 fatalities from the disease.

Cumulative deaths firefighters wildfire COVID-19
Figure 3. Cumulative deaths over time for the baseline scenario with variable infection fatality rates. Note that the vertical axis is not log scaled for this figure. From the study.

The study was conducted by Matthew P. Thompson, Jude Bayham, and Erin Belval. It was supported by Colorado State University and the U.S. Forest Service. (Download the study; large 1.9 Mb file.)

Wildfire smoke and COVID-19

Preliminary evidence suggests exposure to wildfire smoke may increase susceptibility to COVID-19

Wildfire Smoke And COVID 19

The U.S. Forest Service has published a three-page fact sheet with information about the impacts of wildfire smoke during the COVID-19 pandemic. It covers the effects of smoke during the pandemic, who is most at risk, symptoms, masks and face coverings, and how to minimize potential health effects from wildfire smoke. The document has useful information and many links to additional materials.

Here are some excerpts:

  • The COVID-19 pandemic is overlapping with the occurrence of wildfires in the United States.
  • Wildfire smoke is a complex mixture of air pollutants that are harmful to human health.
  • Exposure to air pollutants in wildfire smoke can irritate the lungs, cause inflammation, alter immune function, and increase susceptibility to respiratory infections, likely including COVID-19.
  • Recent scientific publications (Conticini et al., 2020 & Travaglio et al., 2020) suggest that air pollutant exposure worsens COVID-19 symptoms and outcomes.
  • Those with or recovering from COVID-19 may be at increased risk of health effects from exposure to wildfire smoke due to compromised heart and lung function caused by the disease.
  • Although N95 respirators provide protection from wildfire smoke, they might be in short supply as frontline healthcare workers use them during the pandemic.
  • Cloth face coverings that are used to slow the spread of COVID-19 offer little protection against harmful air pollutants in wildfire smoke because these coverings do not capture most small particles in smoke.
Satellite photo smoke Australia fires
Satellite photo of smoke from fires in New South Wales and Victoria January 4, 2020. The red areas represent heat.

Firefighter suicide in Illinois — could it happen in your organization?

Rest in peace, Nicole Hladik

All suicides are tragic, but when it happens to a young firefighter who had been on the job for less than a year it is especially so. Nicole Hladik was not a wildland firefighter, but could it happen in any fire organization?

From FirefighterCloseCalls.com:


FIREFIGHTER TAKES HER OWN LIFE.
A family is searching for answers after a 27-year-old Hinsdale Firefighter (Illinois) who died by suicide. Firefighter Nicole Hladik was the only female firefighter at the Hinsdale Fire Department and the third in the town’s history. “Nicki was a bright rising star in the fire service, she was beloved by all of us of course and very happy early on,” Brian Kulaga, Hladik’s uncle, said.

But Kulaga said something changed recently.

“Then she traded shifts and suddenly just a lot of negativity and then leading up to today, which was obviously a complete surprise to all of us,” he said. Hladik died by suicide Tuesday and her brother Joseph Hladik said it was a complete shock. “Super active, super fit, a family person, a great friend, she’s my sister but my best friend,” he said. Hladik’s family said it doesn’t make sense. “Our goal is, we just want someone to look into this, it’s not an accusation. It’s just the facts are, how could someone who was so happy and loved what she was doing go from one spectrum to the other end? It just doesn’t make any sense,” Joseph Hladik said.


Newspaper stories about Nicole Hladik shortly after she was hired at the Hinsdale Fire Department:
–The Hinsdalean, October 9, 2019:  Village’s Newest Firefighter Is Happy To be “One Of The Gang”
–Chicago Tribune, October 20, 2019: Shout Out: Nicole Hladik of Willowbrook-Hinsdale’s newest Firefighter


Suicide rates among wildland firefighters have been described as “astronomical.

Help is available for those feeling really depressed or suicidal.

Wildland firefighters’ invisible injuries can be life-threatening

A real-life example after the line of duty death of a fellow firefighter

David Ruhl memorial service
Attendees at the memorial service for David Ruhl in Rapid City, South Dakota, August 9, 2015. Photo by Bill Gabbert.

During his 14 years working for the Bureau of Land Management as a wildland firefighter, a fire that Danny Brown responded to on July 30, 2015 changed his life in ways that most of us cannot fathom. Mr. Brown was one of the first to find the burned body of his friend David Ruhl who was entrapped and killed during the initial attack of the Frog Fire in northern California.

An excellent article by Mark Betancourt in High Country News describes the upheaval that occurred in Mr. Brown’s life, how he tried to deal with it, and how the government’s system for treating on the job injuries failed.

Here is a brief excerpt:

The trauma Brown sustained that day could happen to any wildland firefighter. It drove him out of the career he loved and the community that came with it, and to his agony it limited his ability to support his wife and their three children. He was eventually diagnosed with chronic PTSD — post-traumatic stress disorder — and in his most desperate moments, he thought about taking his life. Adding to his suffering was the feeling that he had been abandoned by the government that put him in harm’s way.

A number of people bent over backwards trying to help Mr. Brown receive the professional help he badly needed, including a friend, a supervisor, the Wildland Firefighter Foundation, and Nelda St. Clair, a consultant who coordinates fire-specific crisis intervention and mental fitness for federal and state agencies.

Federal agencies that employe wildland firefighters (but call them technicians) hire them to perform a hazardous job. A percentage of them in the course of their career will be involved directly or indirectly with a very traumatic event. Many of them will power through it with no serious effects, at least outwardly. But others will suffer unseen injuries after having performed their duties.

These federal agencies do not have an effective system or procedure for helping their employees heal from chronic PTSD — post-traumatic stress disorder —  incurred while on the job. Untreated, chronic PTSD can lead to suicide.

Ms. St Clair tries to keep track of how many wildland firefighters take their own lives each year. Her unofficial tally suggests as many die by suicide as in the line of duty.

I can’t help but think that if the job title of these “technicians” was instead, “firefighter”, it might be easier for the hierarchy to understand, and get them the professional support some of them so desperately need. Range Technicians have different job stresses than wildland firefighters. In some cases chronic PTSD is an issue of life and death, not something we can keep ignoring.

If you are a firefighter of part of his or her family, you need to read the article in High Country News. If family members recognize the symptoms it could be helpful.

If you are in an influential position in the federal land management agencies you need to read the article. Look at the firefighters in the photo above who were attending the memorial service for Mr. Ruhl. Do what you can to ensure that no other employees are forced to suffer like Mr. Brown and no doubt others, have.

If you are a federal Senator or Representative, you need to read the article. Then introduce and pass legislation so that other “technicians” do not have to suffer like Mr. Brown.

Read the article.


Help is available for those feeling really depressed or suicidal.

Wildfire smoke worsens coronavirus risk, putting firefighters in extra danger

Researchers found that wildfire smoke exposure can lead to an increase of other pathogens in lungs.

Norbeck prescribed fire Wind Cave National Park
A firefighter at the end of the day, igniting the Norbeck prescribed fire in Wind Cave National Park in the Black Hills of South Dakota, Oct. 20, 2014. Photo by Bill Gabbert.

By Luke Montrose, Assistant Professor of Community and Environmental Health, Boise State University

(This article first appeared at The Conversation)

As summer approaches, two forces of nature are on a collision course, and wildland firefighters will be caught in the middle.

New research suggests that the smoke firefighters breathe on the front lines of wildfires is putting them at greater risk from the new coronavirus, with potentially lethal effects.

At the same time, firefighting conditions make precautions such as social distancing and hand-washing difficult, increasing the chance that, once the virus enters a fire camp, it could quickly spread.

As an environmental toxicologist, I have spent the last decade expanding our understanding of how wood smoke exposure impacts human health. Much of my current research is focused on protecting the long-term health of wildland firefighters and the communities they serve.

‘Camp crud’ and the dangers of air pollution

People have long understood that the air they breathe can impact their health, dating back more than 2,000 years to Hippocrates in his treatise on Air, Water, and Places. Today, there is a growing consensus among researchers that air pollution, specifically the very fine particles called PM2.5, influences risk of respiratory illness. These particles are a tiny fraction of the width of a hair and can travel deep into the lungs.

Italian scientists reported in 2014 that air pollutants can increase the viral load in the lungs and reduce the ability of specialized cells called macrophages to clear out viral invaders.

Researchers in Montana later connected that effect to wood smoke. They found that animals exposed to wood smoke 24 hours before being exposed to a pathogen ended up with more pathogen in their lungs. The researchers showed that wood smoke exposure decreased the macrophages’ ability to combat respiratory infection.

Now, new evidence suggests that long-term exposure to PM2.5 air pollution, which is produced by sources such as wildfirespower plants and vehicles, may make coronavirus particularly deadly.

Researchers from the Harvard T.H. Chan School of Public Health conducted a nationwide study of county-level data and found that even a small increase in the amount of PM2.5 from one U.S. county to the next was associated with a large increase in the death rate from COVID-19. While small increases in PM2.5 also raise the risk of death from other causes for older adults, the magnitude of the increase for COVID-19 was about 20 times greater. The results were released last week, before the usual peer review process was conducted, to help warn people of the risks.

Taken together, these findings suggest that air pollution, including wood smoke, could increase the risk that wildland firefighters will develop severe COVID-19 symptoms.

That probably doesn’t surprise seasoned firefighters.

They’re already familiar with “camp crud,” a combined upper and lower respiratory illness accompanied by cough and fatigue that has become common in firefighting camps.

The National Wildfire Coordinating Group, in its guidance on infectious disease, has pointed out that “the close, overlapping living conditions of an incident command post lends itself to rapid spreading of contagious microorganisms, as witnessed by the common outbreaks of ‘camp crud.’ Outbreaks also have a history of spreading from incident to incident as people are reassigned.”

How to protect wildland firefighters

So, what can be done to avoid the spread of COVID-19 among wildland firefighters and prevent them from being vectors in the communities they serve?

In some areas, officials have been delaying firefighter training sessions and brush-clearing operations that would normally be underway now. But while that might protect firefighters from exposure right now, it can be put off for only so long. Wildfires have already broken out in several states, and delaying controlled burns leaves more fuel when fires get out of control.

The National Wildfire Coordinating Group’s guidance on infectious disease encourages planning ahead so personal protective equipment is available and maintaining records of symptoms so illnesses can be tracked and stopped from spreading.

The guidance also calls for better camp hygiene, providing access to medical care, making isolation possible and coordinating cross-agency communication about the public health risks.

Firefighter camps are not typically well outfitted to promote good personal hygiene. Improving those conditions could help prevent a virus’s spread, such as by adding hand-washing stations and possibly mobile shower units. Single-person tents would allow for more effective social distancing.

Camp personnel should also have access to thermometers and coronavirus test kits. Protocols for quarantining and removing infected firefighters from the field should not only be implemented but practiced.

Also missing from the National Wildfire Coordinating Group’s guidance are policies on traveling to and from training sites, working within communities and traveling from camp. Social distancing may not always be possible, so protective gear, such as face masks, should be made available and their use encouraged.

firefighters crew Whitetail Fire 3-8-2017 Photo by Bill Gabbert
Firefighters on the Whitetail Fire in the Black Hills of South Dakota, March 8, 2017. Photo by Bill Gabbert.

A recent paper from Belgium suggests that even some of the ways firefighters operate in the field should be reconsidered to protect against the virus’s spread. It shows how droplets released when a person exhales can travel farther than six feet during heavy activity. For firefighters, that could mean walking farther apart and in a V-shaped delta formation, rather than a traditional line, to reach the fire.

It is also important to consider that frontline firefighters are often younger and could be asymptomatic but still able to spread the virus, so their contact with with rural community members, such as volunteer firefighters and ranchers, should be considered.

Finally, a system for cross-state communication should be engaged to facilitate sharing of best practices and lessons learned. It also could help track the movement of firefighters across the region.

The safety of rural western communities depends on the wildland firefighters and their ability to respond to emergencies. Protecting their health helps protect public health, too.

Federal employee suicide rate in 2018 was five times higher than private industry

Suicide Helping hands
St.Jude Progress

Wildland firefighters are not alone in their high rate of suicide.

From Fedsmith.com January 8, 2019:

Suicides accounted for 28% of the 124 Federal employee job-related deaths in 2018.

In contrast, suicides accounted for only 5% of the 4,779 private industry employees who died on the job in 2018.

It is OK to ask someone if they are thinking about suicide. Some people think this will spur suicide attempts but this is not accurate. Encouraging them to talk could be the first step leading them to safety.


Help is available for those feeling really depressed or suicidal.

Thanks and a tip of the hat go out to Jim. Typos or errors, report them HERE.