Expert explains climate change impact on infectious diseases

DENVER — Climate change impacts Colorado in a variety of ways, but some effects are not commonly discussed.

“When it comes to temperatures, temperatures are increasing day to day, week to week, month to month, and year to year,” said Andy Hoell, a research meteorologist at the National Oceanic and Atmospheric Administration (NOAA) Physical Sciences Laboratory in Boulder. “What we tend to see in a warmer climate is more extreme precipitation.”

Using statistics and the history of weather and climate extremes, Hoell is able to diagnose what can be attributed to climate change.

“The work that I do is directly applicable to water resources, agriculture. So if you don’t have an appreciation for the effect of climate change on naturally occurring features, like droughts and floods, then you’re not going to be able to know how to anticipate that in the future, whether the future is the next week, the next year, or the next 10 years,” said Hoell.

Natural disasters are what most people think about when discussing climate change, but Dr. Michelle Barron’s head instantly goes to infectious diseases.

“What does that do to animals and insects and all these other things that transmit infections?” asked Barron, who is the senior medical director of infection prevention and control for UCHealth. “It’s going to change how we think about geographic infections.”

Barron said mosquitoes thrive with lots of precipitation, and ticks love the growth that comes from the rainfall, meaning they are changing where they migrate. It makes her think about West Nile virus and Lyme disease, or even worse infectious diseases.

“Mosquitoes that carry malaria are in Florida right now. That is pretty big deal… I don’t know that was in people’s minds of like, isn’t that weird? Like, malaria is not something you get in the United States. I mean, you did back in the 1800s, but not anytime recent,” Barron said. “The fact that happened means we’re already on that trajectory.”

Barron said rodents and birds are also changing their migratory patterns as a result of climate change. Birds can carry avian flu, and rodents can transmit hantavirus.

“There was a recent case of hantavirus in Wyoming, in Cheyenne. Definitely not the Four Corners, right? So, it’s happening already. It’s at a scale that it hasn’t really hit people’s awareness like it should,” said Barron.

Barron said climate change means diseases normally associated with travel will soon become part of every day life, and geographic infections will change over time.

“Which is not good, if you ask me,” said Barron. “Because some of them are pretty terrible, the infections.”