Australian public health authorities have been urged to prepare for a possible increase in severe COVID-19 cases during the local bushfire season, following a QUT-led study that suggests there was a strong link between wildfire smoke exposure and increased COVID-19 hospitalisations in New York State after the 2023 Quebec wildfires.
The study, published in the Journal of Public Health Research & Practice, tracked hospitalisation trends across New York State, which neighbours Quebec in Canada, and compared them with air pollution levels – specifically PM2.5 from wildfire smoke.
PM2.5 is a fine particulate matter known to penetrate deep into the lungs, which can exacerbate respiratory conditions such as asthma.
The Brisbane research team used advanced statistical modelling to track hospitalisation trends across 62 counties in New York State in 2022 and 2023 and found a consistent increase in COVID-19 hospitalisations two weeks or more after wildfire smoke from Canada spread over the border.
Each unit increase in the PM2.5 level was associated with up to 7 per cent higher risk of hospitalisation.
The study authors say their findings underscore the potential effect more frequent and extreme environmental events, such as the Quebec wildfires, can have on the risk of hospitalisation due to infectious diseases such as COVID-19.
The study was led by medical researcher Dr Javier Cortes-Ramirez from the QUT School of Public Health and Social Work and the QUT Centre for Data Science.
The research team also included QUT researchers Vishal Singh and Jialu Wang, and Dr Ruby N. Michael from Griffith University.
"This analysis highlights the importance of environmental health research and the need to support further studies with individual level data to identify any causality links between wildfire emissions and emerging infectious diseases such as COVID-19," Dr Cortes-Ramirez said.
"With Australia heading into another potentially severe bushfire season, we need to recognise the broader health risks posed by smoke exposure – especially for vulnerable populations.
"We need to better understand the links between severe natural events and emerging respiratory infections to protect people's health."
Dr Cortes-Ramirez said the research team hoped the study's findings would help hospitals and the broader health sector prepare for post-wildfire health services demand and inform policy decisions around air quality and emergency planning.
They have shared their findings with the New York health department.
Main image at top: Smoke rises above a forest fire in Alberta, Canada. Photo by Izzy E on Unsplash.
