As Vermont’s climate gets warmer and wetter from climate change we will need to plan for potential health impacts that these changes will have on Vermonters. There will be more days of “extreme” heat, more pollen in the air, and larger populations of ticks carrying infectious diseases like Lyme disease.
Across the United States and around the globe, serious health issues are already on the rise as a result of changes in climate. This is one more important reason to work together to reduce greenhouse gas emissions.
How Hot is Too Hot?
We already know that Vermonters are at greater risk of serious heat-related health impacts and even death when the temperature climbs above 87°F degrees. During the decade between 2004 and 2013, Vermonters were eight times more likely to visit emergency rooms for heat complaints on days when the temperature reached 87°F or greater, and on these very hot days there was an increase of one additional death per day among those over 65 years old.
Although 87°F may not seem very hot, Vermonters may be particularly at risk because we are not used to hot temperatures so we are not prepared. Many Vermont homes do not have air conditioning, and many Vermonters work and play hard outside during the summer. In addition, our population is older, so there are more Vermonters who are at higher risk.
In the future, we can expect more days each year when temperatures reach unhealthy levels. On average over the past 30 years, there have been about six days per year when temperatures reached or exceeded 87°F. Projections by climate scientists show that we can expect 15 to 20 of these hot days per year by 2050, and 20 to 34 by the end of the century.
Tick and Mosquito Borne Diseases on the Rise
Reported cases of Lyme disease and anaplasmosis, both transmitted by blacklegged (deer) ticks, have increased in Vermont in recent years. Over 380 confirmed cases of Lyme disease have been reported each year since 2011, up from 60 or fewer before 2006. Vermont had the 2nd highest incidence rate of Lyme disease in the nation in 2014. Confirmed cases of anaplasmosis have also increased from 3 in 2010 to 67 in 2014. Diseases transmitted by mosquitos, such as eastern equine encephalitis and West Nile virus, have also been reported in Vermont in recent years.
Warming conditions are one of several factors that have contributed to an increased distribution and abundance of black-legged ticks in northern states that can transmit pathogens causing Lyme disease, anaplasmosis, and other diseases. Climate change is expected to further expand the black-legged tick northward range and lengthen the tick activity season, likely leading to an increased risk of tick-borne diseases in Vermont in the future. Warmer and wetter conditions will likely increase mosquito abundance and activity, and may facilitate the introduction of mosquitos that can transmit pathogens not currently found in Vermont.
More Pollen Means More Allergies
Climate change is lengthening the growing season in Vermont, a change which may also extend the length of the pollen allergy season. Recent research from the Midwest reported that the ragweed pollen season has increased by over two weeks since 1995 in northern states. The longer growing season, combined with increased plant growth due to higher levels of carbon dioxide in the air, is likely to increase the allergenic pollen in the air we breathe. Further increases in allergy triggers could result in widespread respiratory impacts to Vermonters.
The prevalence of asthma in Vermont adults increased by about 50% between 2000 and 2010. Adult asthma prevalence in Vermont has been significantly higher than the national rate since 2007, and was the 7th highest in the U.S. in 2013. About 67,000 Vermonters report having asthma, including about 13,000 children. Further increases in allergy triggers could have widespread respiratory impacts to Vermonters.
These are just a few of the current and future health impacts from our changing climate. Learn about others -- from safety risks from flooding to exposure to blue-green algae -- at the Health Department’s Climate & Health website
The Health Department’s website also has much more information about extreme heat, tick borne diseases, and mosquito borne diseases. The Health Department also has a tick tracker where Vermonters can report on tick encounters, providing the Department and the public with valuable information about locations and types of ticks found in Vermont.