Physician work hours, especially for male doctors, have declined since 1987

CANADIAN MEDICAL ASSOCIATION JOURNAL

Physicians in Canada, especially male physicians, are working fewer hours than they did 3 decades ago, and these long-term trends must be considered in workforce planning, according to new research in CMAJ (Canadian Medical Association Journal) https://www.cmaj.ca/lookup/doi/10.1503/cmaj.231166.

"Canadian physicians' work hours, crucial for health care access and planning, have seen a long-term decline, especially among male and married physicians, suggesting a shift towards better work–life balance," said Dr. Boris Kralj, Department of Economics, Centre for Health Economics & Policy Analysis, McMaster University, Hamilton, Ontario.

Using Statistics Canada's Labour Force Survey, researchers from McMaster University conducted a study on long-term trends in physician work hours, with data from 1987 to 2021. They hope that the findings will help governments make smart health care policy decisions, inform physician work force planning, and foster gender equity.

Highlights:

• Compared with the general population, physicians worked more hours per week, about 20% more hours in 2021
• Weekly physician hours decreased 13.5% from 52.7 hours per week in 1987 to 45.6 in 2019
• Average hours worked by male physicians declined markedly beginning around 1997
• No differences in declines in hours among urban versus rural settings, incorporated versus unincorporated physicians, physicians younger or older than 45 years, or those with or without children under age 5 years, were apparent
• Hours worked varied by province, but these differences declined over time

The early part of the COVID-19 pandemic was associated with a 15% decline in working hours, with an 11% decline among male physicians and a 20% decline in hours worked by female physicians in the second quarter of 2020. However, by the end of 2020, hours worked reverted to prepandemic levels.

The study's authors suggest that a desire for better work–life balance may be driving these long-term trends. For a long time, doctors have been expected to work very long hours and be available all the time. This has led to unhealthy workplaces.

"[W]e propose that a shift in male physicians' preferences toward achieving better work–life balance is an important contributing factor. The question of whether these trends are related to physician burnout is relevant. Characterized by emotional exhaustion, depersonalization, detachment from work, and reduced personal accomplishment, burnout can lead to negative effects on health, lower productivity, reduced work hours, and even exiting medical practice," write the authors.

They found no evidence that higher payments contributed to physicians working fewer hours. The observed decrease in hours persisted during periods of both rising and stable payment levels.

These trends highlight the need for Canada to have enough doctors to meet its population's evolving needs. It is important for policy-makers to consider not just how many doctors there are, but also how many hours they work.

"The way forward will likely involve policy-makers increasing the size of the medical workforce — including physicians and other occupations involved in interdisciplinary care — faster than population growth to accommodate historical and potential future hour reductions (and increasing demand from an aging population)," write the authors.

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JOURNAL

Canadian Medical Association Journal

DOI

10.1503/cmaj.231166 

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Long-term trends in the work hours of physicians in Canada

ARTICLE PUBLICATION DATE

25-Mar-2024

 

Sweeping review reveals latest evidence on the diagnosis, treatment, and monitoring of ADHD

A comprehensive literature review from USC researchers summarizes the most robust findings on addressing ADHD in children and adolescents, which will inform updated clinical practice guidelines from the American Academy of Pediatrics

KECK SCHOOL OF MEDICINE OF USC

Hundreds of studies are published each year on attention deficit hyperactivity disorder (ADHD), but more work is needed to ensure those findings improve lives.

With input from expert stakeholders across the field, researchers at the Southern California Evidence Review Center, part of the Keck School of Medicine of USC, have synthesized the latest insights so that they can ultimately inform clinical practice. Broadly, they found that both medications and psychosocial treatments work for treating ADHD and that children with the condition can and do get better.

“We have more research than ever on ADHD, but we need to summarize it in a reliable and valid way,” said Susanne Hempel, PhD, a professor of clinical population and public health sciences at the Keck School of Medicine and director of the Southern California Evidence Review Center, who oversaw the work.

The team, which included researchers from the Southern California Evidence-based Practice Center, the Keck School of Medicine’s division of child psychiatry and the Children’s Hospital Los Angeles Behavioral Health Institute, reviewed more than 23,000 publications on ADHD. Their work was commissioned by the Agency for Healthcare Research and Quality and funded by the Patient-Centered Outcomes Research Institute.

The results, just published in two companion papers in the journal Pediatrics, answer big questions about what works to effectively diagnose and treat ADHD, and point to ongoing gaps in the research, including how best to monitor the condition’s progression over time. Clinicians selected by the American Academy of Pediatrics (AAP) will now use the evidence review to create updated clinical guidelines that inform best practices in ADHD care across the nation.

“Parents, teachers and providers need evidence-based information about ADHD,” Hempel said. “We included only the most robust studies in our review, which enables us to make strong evidence statements.”

New findings on diagnosis and treatment

Before beginning the literature review, the research team developed their questions and protocols in collaboration with ADHD experts across the field to ensure they were asking and answering questions that could directly benefit patients, families and providers. During the process, the researchers also posted their preliminary findings and welcomed feedback during a 45-day public comment period.

The team conducted an extensive search that was not restricted to diagnostic tools or treatment approaches already known to be effective. From more than 23,000 publications, the researchers selected 550 studies for the final analysis. Studies were selected if they met the team’s rigorous inclusion criteria, which prioritized rigorous study designs such as randomized controlled trials.

For diagnosis of ADHD, many tools are available, including parent and teacher rating scales, patient self-reports, neuropsychological tests, EEG approaches, imaging, biomarkers, activity monitoring and observation. For several approaches, the researchers found a substantial variation in results, with some studies indicating a given method was highly effective and others indicating that it performed poorly. “We’re getting better at diagnosing ADHD, but research is still characterized by a lot of variation,” Hempel said.

Many treatments for ADHD have been rigorously tested, building a strong evidence base for medications (including both stimulants and non-stimulants), as well as psychosocial approaches, such as behavior modification. Other non-drug treatments the team analyzed include cognitive training, neurofeedback, physical exercise, nutrition and supplements, parent support, and school interventions.

“Medications have the strongest evidence for improving not only ADHD symptoms, but also other problems that often accompany ADHD, such as oppositional and disruptive behaviors,” said Bradley Peterson, MD, director of the Institute for the Developing Mind at Children's Hospital Los Angeles (CHLA) and the lead author of the review.

Monitoring ADHD over time

In addition to reviewing the evidence on diagnosis and treatment, the researchers explored what is known about ongoing monitoring of ADHD: How can providers assess whether a child or adolescent needs to continue treatment for the condition? Experts across the field agreed that the question is a critical one, but few studies have explored the question. The evidence review team concluded that more research is needed on monitoring ADHD over time.

The publications will now be used to support an update of the AAP’s clinical practice guidelines for ADHD, providing up-to-date advice for how best to diagnose, evaluate and treat the condition.

“The overarching takeaway: ADHD is treatable. There are lots of studies that can show us that children absolutely can get better,” Hempel said.

About this research

In addition to Drs. Peterson and Hempel, the study’s other authors are Joey Trampush, Morah Brown, Margaret Maglione, Maria Bolshakova, Mary Rozelle, Jeremy Miles, Sheila Pakdaman and Aneesa Motala among others from the Southern California Evidence Review Center, Keck School of Medicine, University of Southern California.

This work is supported by the Agency for Healthcare Research and Quality [Contract No. 75Q80120D00009] and the Patient-Centered Outcomes Research Institute [Publication No. 2023-SR-03]. More information about AHRQ’s Effective Health Care program, which funds this work, may be found at: https://effectivehealthcare.ahrq.gov/about.

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JOURNAL

PEDIATRICS

DOI

10.1542/peds.2024-065787 

METHOD OF RESEARCH

Meta-analysis

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Treatments for ADHD in Children and Adolescents: A Systematic Review

ARTICLE PUBLICATION DATE

25-Mar-2024

 

Honey bees at risk for colony collapse from longer, warmer fall seasons

Cold storage for colonies could help mitigate climate change effects

Peer-Reviewed Publication

WASHINGTON STATE UNIVERSITY

 

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WASHINGTON STATE UNIVERSITY RESEARCHERS AND STUDENTS COLLECT SAMPLES AND PERFORM HONEY BEE COLONY HEALTH ASSESSMENTS IN ORCHARDS NEAR MODESTO, CA. EVERY YEAR MORE THAN 2 MILLION HONEY BEE HIVES FROM ACROSS THE COUNTRY ARE MOVED TO CALIFORNIA TO POLLINATE ALMOND TREES IN FEBRUARY. TO MANAGE BEE HEALTH AND THE LOGISTICS OF THE MOVE, MANY COMMERCIAL BEEKEEPERS ARE STARTING TO USE INDOOR COLD STORAGE FOR THEIR HIVES – A PRACTICE THAT RESEARCHERS HAVE FOUND MIGHT ALSO HELP PREVENT COLONY COLLAPSES FROM LONGER, WARM AUTUMNS DUE TO CLIMATE CHANGE.

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CREDIT: BRANDON HOPKINS, WASHINGTON STATE UNIVERSITY

PULLMAN, Wash. – The famous work ethic of honey bees might spell disaster for these busy crop pollinators as the climate warms, new research indicates.

Flying shortens the lives of bees, and worker honey bees will fly to find flowers whenever the weather is right, regardless of how much honey is already in the hive. Using climate and bee population models, researchers found that increasingly long autumns with good flying weather for bees raises the likelihood of colony collapse in the spring.

The study, published in Scientific Reports, focused on the Pacific Northwest but holds implications for hives across the U.S. The researchers also modeled a promising mitigation: putting colonies into indoor cold storage, so honey bees will cluster in their hive before too many workers wear out.

“This is a case where a small amount of warming, even in the near future, will make a big impact on honey bees,” said lead author Kirti Rajagopalan, a Washington State University climate researcher. “It’s not like this is something that can be expected 80 years from now. It is a more immediate impact that needs to be planned for.”

For this study, researchers ran simulations through a honey bee population dynamics model using climate projections for 2050 and the end of the century at 2100. They found that honey bee colonies that spend the winter outside in many areas of the Pacific Northwest would likely experience spring colony collapses in both the near- and long-term scenarios. This also occurred under a simulation where climate change continued as it is progressing now and one where greenhouse gas emissions were reduced in the near future.

Worker honey bees will forage for food whenever temperatures rise above about 50 degrees Fahrenheit. When it gets colder, they cluster in the hive, huddling with other bees, eating honey reserves and shivering, which helps keep the bees warm. In the spring, the adult worker bees start flying again. That means they also start dying. If too many older worker bees die before their replacements emerge ready to forage, the whole colony can collapse. Scientists have estimated this happens when there are fewer than 5,000 to 9,000 adult bees in the hive.

This study found that colonies wintering outside in colder areas like Omak in the far north of Washington state might still do all right under climate change. But for honey bee colonies in many other places, like Richland, Washington near the border of Oregon, staying outside in the winter would mean the spring hive population would plummet to fewer than 9,000 adults by 2050 and less than 5,000 by the end of the century.

The authors note that the simulations just looked at seasonal factors like temperature, wind and the amount of daylight, making them fairly conservative models.

“Our simulations are showing that even if there is no nutritional stress, no pathogens, no pesticides – just the conditions in fall and winter are enough to compromise the age structure of a colony. So when the hive comes out of winter, the bees are dying faster than they're being born,” said co-author Gloria DeGrandi-Hoffman, a research leader at the U.S. Department of Agriculture’s Carl Hayden Bee Research Center.

The researchers also simulated a potential mitigation, placing honey bee hive boxes in cold storage so the bees start to cluster earlier and save workers. For instance, in the Richland scenarios, by the end of the century, having bees in cold storage from October to April would boost the spring hive population to over 15,000 compared to around 5,000 to 8,000 if they were kept outside.

A relatively new practice, cold storage is gaining popularity among commercial beekeepers to help manage bee health and for the logistics involved in moving hives to California to pollinate almond trees in February, an event that draws more than two million hives from across the country.

“A lot of beekeepers are already practicing this management technique of storing bees indoors because it has a lot of immediate potential to help in a number of ways,” said co-author Brandon Hopkins, a WSU entomologist. “These findings demonstrate that there are additional benefits to this practice for the survival of colonies in a changing climate.”

This research received support from the Washington Department of Agriculture’s Specialty Crop Block Grant.

Washington State University researchers and students collect samples and perform honey bee colony health assessments in orchards near Modesto, CA. Every year more than 2 million honey bee hives from across the country are moved to California to pollinate almond trees in February. To manage bee health and the logistics of the move, many commercial beekeepers are starting to use indoor cold storage for their hives – a practice that researchers have found might also help prevent colony collapses from longer, warm autumns due to climate change.

WSU beeresearch3 (IMAGE)

WASHINGTON STATE UNIVERSITY

Washington State University researchers and students collect samples and perform honey bee colony health assessments in orchards near Modesto, CA. Every year more than 2 million honey bee hives from across the country are moved to California to pollinate almond trees in February. To manage bee health and the logistics of the move, many commercial beekeepers are starting to use indoor cold storage for their hives – a practice that researchers have found might also help prevent colony collapses from longer, warm autumns due to climate change.

CREDIT

Brandon Hopkins, Washington State University

JOURNAL

Scientific Reports

DOI

10.1038/s41598-024-55327-8 

ARTICLE TITLE

Warmer autumns and winters could reduce honey bee overwintering survival with potential risks for pollination services

ARTICLE PUBLICATION DATE

25-Mar-2024

 

Persian plateau unveiled as crucial hub for early human migration out of Africa

GRIFFITH UNIVERSITY

 

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PEBDEH CAVE LOCATED IN THE SOUTHERN ZAGROS MOUNTAINS. PEBDEH WAS OCCUPIED BY HUNTER-GATHERERS AS EARLY AS 42,000 YEARS AGO.

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CREDIT: MOHAMMAD JAVAD SHOAEE

A new study combining genetic, palaeoecological, and archaeological evidence has unveiled the Persian Plateau as a pivotal geographic location serving as a hub for Homo sapiens during the early stages of their migration out of Africa.  

This revelation sheds new light on the complex journey of human populations, challenging previous understandings of our species' expansion into Eurasia. 

The study, published in Nature Communications, highlights a crucial period between approximately 70,000 to 45,000 years ago when human populations did not uniformly spread across Eurasia, leaving a gap in our understanding of their whereabouts during this time frame. 

Key findings from the research include: 

• The Persian plateau as a hub for early human settlement: Using a novel genetic approach combined with palaeoecological modelling, the study revealed the Persian Plateau as the region where from population waves that settled all of Eurasia originated.

• This region emerged as a suitable habitat capable of supporting a larger population compared with other areas in West Asia. 

• Genetic resemblance in ancient and modern populations: The genetic component identified in populations from the Persian Plateau underlines its long-lasting differentiation in the area, compatible with the hub nature of the region, and is ancestral to the genetic components already known to have inhabited the Plateau.

• Such a genetic signature was detected thanks to a new approach that disentangles 40,000 years of admixture and other confounding events. This genetic connection underscores the Plateau's significance as a pivotal location for early human settlement and subsequent migrations. 

Study co-author Professor Michael Petraglia, Director of Griffith University’s Australian Research Centre for Human Evolution, provided a much clearer picture of these early human movements. 

“Our multidisciplinary study provides a more coherent view of the ancient past, offering insights into the critical period between the Out of Africa expansion and the differentiation of Eurasian populations,” Professor Petraglia said.  

“The Persian Plateau emerges as a key region, underlining the need for further archaeological explorations." 

First author Leonardo Vallini of the University of Padova, Italy, said: “The discovery elucidates a 20,000 year long portion of the history of Homo sapiens outside of Africa, a timeframe during which we interacted with Neanderthal populations, and sheds light on the relationships between various Eurasian populations, providing crucial clues for understanding the demographic history of our species across Europe, East Asia, and Oceania.”  

Senior author, Professor Luca Pagani added: “The revelation of the Persian Plateau as a hub for early human migration opens new doors for archaeological exploration, enriching our understanding of our species' journey across continents and highlighting this region's pivotal role in shaping human history.” 

The study ‘The Persian Plateau served as Hub for Homo sapiens after the main Out of Africa dispersal’ has been published in Nature Communications. 

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JOURNAL

Nature Communications

DOI

10.1038/s41467-024-46161-7 

SUBJECT OF RESEARCH

People

ARTICLE TITLE

The Persian Plateau served as Hub for Homo sapiens after the main Out of Africa dispersal

20,000 years of shared history on the Persian plateau

Peer-Reviewed Publication

ESTONIAN RESEARCH COUNCIL

 

IMAGE: 

PERSIAN PLATEAU, THE MOST LIKELY PLACE WHERE THE ANCESTORS OF ALL PRESENT DAY NON AFRICANS LIVED FOR THE 20.000 YEARS THAT FOLLOWED THEIR MIGRATION OUT OF AFRICA. A PERIOD DURING WHICH THEY ALSO MIXED THEIR GENES WITH THE ONES OF THE NEANDERTHALS.

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CREDIT: CREDITS: THE AUTHORS OF THE ORIGINAL PUBLICATION

All present day non African human populations are the result of subdivisions that took place after their ancestors left Africa at least 60.000 years ago. How long did it take for these separations to take place? Almost 20.000 years, during which they were all part of a single population. Where did they live for all this time? We don’t know, yet.

This is a conversation that could have taken place one year ago, now it is possible to give clearer answers to these questions thanks to the study recently published in Nature Communications (1) led by the researchers from the University of Padova, in collaboration with the University of Bologna (Department of Cultural Heritage), the Griffith University of Brisbane, the Max Planck Institute of Jena and the University of Turin.

The ancestors of all present day Eurasians, Americans and Oceanians, moved Out of Africa between 70 and 60 thousand years ago. After reaching Eurasia these early settlers idled for some millennia as a homogeneous population, in a presumably localized area, before expanding their range across the whole continent and beyond. This event set the basis for the genetic divergence between present day Europeans and East Asians, and can be dated to around 45 thousand years ago. On the one hand, the dynamics that led to the broader colonization of Eurasia have been already reconstructed by some of the authors in a previous publication in 2022 (2), and occurred through a series of chronologically, genetically and culturally distinct expansions. On the other hand, the geographic area where the ancestors of all non Africans lived  after the Out of Africa and that acted as a “Hub” for  the subsequent movements of Homo sapiens has been the matter of a long standing debate, with most of West Asia, North Africa, South Asia or even South East Asia having been listed as potentially suitable locations.

In their latest work, the authors deployed a novel genetic approach and identified ancient and modern populations from the Persian Plateau as the ones carrying genetic traces that most closely resemble the features of the Hub population, pinpointing the area as the likely homeland of all early Eurasians. “The most difficult part” says Leonardo Vallini, first author of the study, “has been to disentangle the various confounding factors constituted by 45 thousand years of population movements and admixtures that took place after the Hub was settled”.

The multidisciplinary study also investigated the paleoecological characteristics of the area at the time, and confirmed it as suitable for human occupation, potentially capable of sustaining a larger population than other parts of West Asia. “Identifying the Persian Plateau as a Hub for early human migration opens new doors for archaeological and palaeoanthropological research” added co-author Professor Michael Petraglia of Griffith University in Brisbane.

In fact, the Persian plateau will be the focus of the ERC Synergy Project 'LAST NEANDERTHALS', recently awarded to co-author Stefano Benazzi, professor at the University of Bologna (Department of Cultural Heritage). "In line with the results of the study," says Benazzi, "this ERC project aims to explore and unravel the intricate biocultural events that occurred between 60,000 and 40,000 years ago, focusing also on the Persian Plateau".

“With our work we found a home to 20,000 years of shared history between Europeans, East Asians, Native Americans and Oceanians. This leg of the human journey out of Africa is fascinating, since it is the one where we also met and mixed our genes with the ones of Neanderthals” concluded Professor Luca Pagani, senior author of the study.

References

1. Leonardo Vallini, Carlo Zampieri, Mohamed Javad Shoaee, Eugenio Bortolini, Giulia Marciani, Serena Aneli, Telmo Pievani, Stefano Benazzi, Alberto Barausse, Massimo Mezzavilla, Michael D. Petraglia, Luca Pagani, The Persian Plateau served as Hub for Homo sapiens after the main Out of Africa dispersal, Nature Communications [https://www.nature.com/articles/s41467-024-46161-7]
2. Leonardo Vallini, Giulia Marciani, Serena Aneli, Eugenio Bortolini, Stefano Benazzi, Telmo Pievani, Luca Pagani. Genetics and Material Culture Support Repeated Expansions into Paleolithic Eurasia from a Population Hub Out of Africa, Genome Biology and Evolution, Volume 14, Issue 4, April 2022, evac045, https://doi.org/10.1093/gbe/evac045

 

Link to the study: https://www.nature.com/articles/s41467-024-46161-7

Title: The Persian Plateau served as Hub for Homo sapiens after the main Out of Africa dispersal – «Nature Communications» – 2024

Authors: Leonardo Vallini, Carlo Zampieri, Mohamed Javad Shoaee, Eugenio Bortolini, Giulia Marciani, Serena Aneli, Telmo Pievani, Stefano Benazzi, Alberto Barausse, Massimo Mezzavilla, Michael D. Petraglia, Luca Pagani

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JOURNAL

Nature Communications

DOI

10.1038/s41467-024-46161-7 

METHOD OF RESEARCH

Data/statistical analysis

SUBJECT OF RESEARCH

People

ARTICLE TITLE

The Persian Plateau served as Hub for Homo sapiens after the main Out of Africa dispersal

ARTICLE PUBLICATION DATE

25-Mar-2024

 

Humans pass more viruses to other animals than we catch from them

UNIVERSITY COLLEGE LONDON

Humans pass on more viruses to domestic and wild animals than we catch from them, according to a major new analysis of viral genomes by UCL researchers.

For the new paper published in Nature Ecology & Evolution, the team analysed all publicly available viral genome sequences, to reconstruct where viruses have jumped from one host to infect another vertebrate species.

Most emerging and re-emerging infectious diseases are caused by viruses circulating in animals. When these viruses cross over from animals into humans, a process known as zoonosis, they can cause disease outbreaks, epidemics and pandemics such as Ebola, flu or Covid-19. Given the enormous impact of zoonotic diseases on public health, humans have generally been considered as a sink for viruses rather than a source, with human-to-animal transmission of viruses receiving far less attention.

For the study, the research team developed and applied methodological tools to analyse the nearly 12 million viral genomes that have been deposited on public databases to date. Leveraging this data, they reconstructed the evolutionary histories and past host jumps of viruses across 32 viral families, and looked for which parts of the viral genomes acquired mutations during host jumps.

The scientists found that roughly twice as many host jumps were inferred to be from humans to other animals (known as anthroponosis) rather than the other way round. This pattern was consistent throughout most viral families considered. Additionally, they found even more animal-to-animal host jumps, that did not involve humans.

The team’s work highlights the high and largely underappreciated fact that human viruses frequently spread from humans into wild and domestic animals.

Co-author Professor Francois Balloux (UCL Genetics Institute) said: “We should consider humans just as one node in a vast network of hosts endlessly exchanging pathogens, rather than a sink for zoonotic bugs.

“By surveying and monitoring transmission of viruses between animals and humans, in either direction, we can better understand viral evolution and hopefully be more prepared for future outbreaks and epidemics of novel illnesses, while also aiding conservation efforts.”

The findings also show that, on average, viral host jumps are associated with an increase in genetic changes, or mutations in viruses, relative to their continued evolution alongside just one host animal, reflecting how viruses must adapt to better exploit their new hosts.

Further, viruses that already infect many different animals show weaker signals of this adaptive process, suggesting that viruses with broader host ranges may possess traits that make them inherently more capable of infecting a diverse range of hosts, whereas other viruses may require more extensive adaptations to infect a new host species.

Lead author, PhD student Cedric Tan (UCL Genetics Institute and Francis Crick Institute) said: “When animals catch viruses from humans, this can not only harm the animal and potentially pose a conservation threat to the species, but it may also cause new problems for humans by impacting food security if large numbers of livestock need to be culled to prevent an epidemic, as has been happening over recent years with the H5N1 bird flu strain.

“Additionally, if a virus carried by humans infects a new animal species, the virus might continue to thrive even if eradicated among humans, or even evolve new adaptations before it winds up infecting humans again.

“Understanding how and why viruses evolve to jump into different hosts across the wider tree of life may help us figure out how new viral diseases emerge in humans and animals.”

Cell entry is generally seen as the first step for a virus to infect a host. However, the team found that many of the adaptations associated with host jumps were not found in the viral proteins that enable them to attach to and enter host cells, which points to viral host adaptation being a complex process that remains to be fully understood.

Co-author Dr Lucy van Dorp (UCL Genetics Institute) said: “Our research was made possible only by the countless research teams that have openly shared their data via public databases. The key challenge, moving forward, is to integrate the knowledge and tools from diverse disciplines including genomics, epidemiology, and ecology to enhance our understanding of host jumps.”

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JOURNAL

Nature Ecology & Evolution

DOI

10.1038/s41559-024-02353-4 

METHOD OF RESEARCH

Data/statistical analysis

ARTICLE TITLE

The evolutionary drivers and correlates of viral host jumps

ARTICLE PUBLICATION DATE

25-Mar-2024

 

New UM study reveals unintended consequences of fire suppression

THE UNIVERSITY OF MONTANA

 

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NEW RESEARCH FROM THE UNIVERSITY OF MONTANA SUGGESTS ATTEMPTING TO SUPPRESS ALL WILDFIRES CAUSES THEM TO BURN WITH GREATER SEVERITY. 

 

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CREDIT: UNIVERSITY OF MONTANA PHOTO BY TOMMY MARTINO

MISSOULA – The escalation of extreme wildfires globally has prompted a critical examination of wildfire management strategies. A new study from the University of Montana reveals how fire suppression ensures that wildfires will burn under extreme conditions at high severity, exacerbating the impacts of climate change and fuel accumulation.

The study used computer simulations to show that attempting to suppress all wildfires results in fires burning with more severe ecological impacts, with accelerated increases in burned area beyond those expected from fuel accumulation or climate change.

“Fire suppression has unintended consequences,” said lead author Mark Kreider, a Ph.D. candidate in the forest and conservation sciences program at UM. “We’ve known for a long time that suppressing fires leads to fuel accumulation. Here, we show a separate counter-intuitive outcome.”

Though fire suppression reduces the overall area burned, it mainly eliminates low- and moderate-intensity fires. As a result, the remaining fires are biased to be more extreme, Kreider said. The new study published March 25 in Nature Communications, shows how this “suppression bias” causes average fire severity to increase substantially.

“Over a human lifespan, the modeled impacts of the suppression bias outweigh those from fuel accumulation or climate change alone,” he said. “This suggests that suppression may exert a significant and underappreciated influence on patterns of fire globally.”

Kreider led the research as part of his Ph.D. dissertation work with the support of a National Science Foundation Graduate Research Fellowship.

Fire suppression exacerbated the trends already caused by climate change and fuel accumulation, the study found, causing areas burned to increase three to five times faster over time relative to a world with no suppression.

Suppression, through preferentially removing low- and moderate-severity fire, also raised average fire severity by an amount equivalent to a century of fuel accumulation or climate change.

“By attempting to suppress all fires, we are bringing a more severe future to the present,” said Kreider.

Andrew Larson, Kreider’s Ph.D. adviser and a professor of forest ecology at UM, said this has significant impacts on ecosystems.

“Traditional suppression removes the low-severity fires that help perpetuate healthy forests by consuming fuels and preferentially killing thin-barked tree species,” Larson said. “I wonder how much we are altering natural selection with fire suppression by exposing plants and animals to relatively less low-severity fire and relatively more high-severity fire.”

However, the new findings also show that allowing more low- and moderate-intensity fire can reduce or reverse the impacts of the suppression bias. Suppression strategies that allow fire to burn under moderate weather conditions – while still suppressing fires during more dangerous fire weather – reduced average fire severity and moderated the rate of burned area increase, the team found.

“It may seem counterintuitive, but our work clearly highlights that part of addressing our nation’s fire crisis is learning how to accept more fires burning when safely possible,” said Philip Higuera, a co-author and UM professor of fire ecology. “That’s as important as fuels reduction and addressing global warming.”

Developing and implementing technologies and strategies to safely manage wildfires during moderate burning conditions is essential, Kreider said. This approach may be just as effective as other necessary interventions, like mitigating climate change and decreasing unintentional human-related ignitions.

The article, “Fire suppression makes wildfires more severe and accentuates impacts of climate change and fuel accumulation,” was co-authored by Kreider, Larson, Higuera, William Rice, and Nadia White from the University of Montana, as well as Sean Parks, an ecologist with the Aldo Leopold Wilderness Research Institute.

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JOURNAL

Nature Communications

ARTICLE TITLE

Fire suppression makes wildfires more severe and accentuates impacts of climate change and fuel accumulation

ARTICLE PUBLICATION DATE

25-Mar-2024