Global warming is making Lyme disease “the first epidemic of climate change,” the website Aeon argues in a newly published article receiving substantial media attention. A look at the facts, however, shows no such thing.
Lyme disease is transferred to humans by certain forms of ticks. Aeon presents anecdotal evidence of an increase in tick populations in the northeastern United States. Claiming that ticks don’t like cold weather, Aeos claims global warming is causing the increase in tick populations, which in turn is causing a Lyme disease epidemic.
Aeon doesn’t mention that Lyme disease prospers in the cooler climate of Canada and the northern United States, not the warmer climate of the middle and southern United States. To the extent a warmer climate may be changing the range of the ticks that cause Lyme disease, Aeon acknowledges it is pushing them further north, into less densely populated areas of North America. That is hardly a recipe for an epidemic.
The Aeos article also fails to present any statistics about how many people are being killed by this “epidemic.” That is probably because Lyme disease kills very few people. The U.S. Centers for Disease Control report Lyme disease is “rare as a cause of death in the United States” and during a five-year study found the disease factored in less than 25 deaths per year.
Most damning of all, a study of Lyme disease in the peer-reviewed journal EcoHealth found “the only environmental variable consistently associated with increased risk and incidence was the presence of forests.”
So Aeon makes the argument that global warming is causing a disease that occurs in cool-weather climate to expand further north, into less densely populated regions. The disease kills very few people each year. And scientific studies show forest density is the only environmental factor associated with the disease. Sounds like the “first epidemic of climate change” to us…