Even brief exposure to air pollution increases risk of flu and other respiratory infections in children, Utah-based study finds

(Steve Griffin | The Salt Lake Tribune) Air pollution hangs over the Wasatch Front, as seen on January 5, 2018. A new Utah-based study suggests that even brief exposure to particulate pollution can boost the likelihood of respiratory infections in children.

Utah’s children are more likely to contract viral respiratory infections such as the flu and RSV after exposure to air pollution during the state’s infamous inversions — but it’s not entirely clear why.

According to a new study, Utah patients were more likely to be diagnosed with a variety of lower respiratory infections in the month following an episode of exposure to elevated small-particulate pollution — the kind of air contaminant associated with the kind of cough-inducing inversion that can dwell over the Wasatch Front in winter months.

For every 10 micrograms of small particulate for each cubic meter of air (10 ug/m3), the odds of contracting an infection increased between 15 and 23 percent, according to the report, published in the American Journal of Respiratory and Critical Care Medicine.

The research was based on data collected on the Wasatch Front and compiled by a team from Intermountain Healthcare, Brigham Young University and the University of Utah.

The national standard for short-term levels of particulate pollution, as established by the U.S. Environmental Protection Agency, is currently 35 ug/m3. Year-round, Utah’s levels of particulate pollution are relatively low, but the state has routinely exceeded the EPA’s standard during wintertime inversion episodes over the past decade.

Children ages 3-17 saw the greatest increase in risk during these episodes, said Benjamin Horne, director of cardiovascular and genetic epidemiology at the Intermountain Medical Center Heart Institute and the lead author on the study. But the risk of infection increased in adults and infants as well.

It remains unclear why the risk of infection increased, Horne said, though the researcher theorized that particulate exposure may prime the body for infection in some way, or possibly reduce the immune system’s ability to respond to viral invaders.

It is also unknown as yet whether pollution increased the severity of those infections. Though 26 of the children in the study died within 30 days of being diagnosed with a lower respiratory infection, the number of fatalities was too small to assess whether the infection was worsened by exposure, Horne said.

But given the potentially fatal nature of severe infections from RSV, short for respiratory synctial virus, and influenza — particularly among young children — the study results are reason for concern, he said.

“These are important considerations that we need to think about — how to bring that risk down, on an individual and health system level,” Horne said.

Horne suggested parents adopt a two-pronged approach to prevention. Children should be kept indoors during episodes of elevated pollution, and should be especially vigilant about hand-washing and other sanitary measures.

The study’s results were “no reason to panic,” Horne said, “but just another reason to help children avoid infections and be aware that during higher air pollution periods, ensure you are taking preventative measures.”