The health implications of seasonal allergies don’t get the attention they deserve; we might just brush them off as annoyances many of us have to endure.
Climate change, unfortunately, is making these health consequences worse than ever and worthy of more attention from health reporters.
Each year, reports like this one come out asserting that seasonal allergies are unusually bad; but are they actually getting worse? The severity of allergies typically changes yearly depending on a number of seasonal variables, but the trend has continued to be bad in the U.S. Many researchers have speculated that allergies are getting worse and that climate change is to blame.
Warmer weather, higher carbon dioxide levels and changing weather patterns are combining to make allergies more severe. If action is not taken to avoid worsening climate change, allergies for millions of Americans will continue to get worse.
Seasonal allergies happen when our immune system responds to pollen or fungal spores as if they were an infectious agent. When this happens, many people experience runny noses, itchy eyes or scratchy throats, which can feel cold-like. For people with asthma or respiratory issues, they can have a more serious reaction that requires medical attention.
The best way to avoid a future in which seasonal allergies feel like a serious illness is to act to limit the most severe effects of climate change by reducing greenhouse gas emissions. Health care journalists can help readers make that connection by explaining how climate change is increasing pollen counts, which have a direct impact on human health.
How we got here
A warming climate gives the growing season an earlier start and prolongs it in the fall. Between 1995 and 2011, warmer temperatures in the U.S. have caused the pollen season to be 11 to 27 days longer, according to the Asthma and Allergy Foundation of America. These are added days of growth and pollen production, which prolong allergenic exposure. Primary culprits for seasonal allergies (or “hay fever”) are ragweed, mold and tree and grass pollen.
Carbon dioxide, a greenhouse gas released when burning fossil fuels, is also playing a part. Pollen-producing plants take in CO2 as part of photosynthesis, which causes them to mature faster, grow bigger and produce more pollen. While trees do a great job of filtering pollutants and cooling surrounding areas, they are not adjusted to climate change and will produce more pollen when CO2 levels are higher.
Cities can be uniquely threatening to the 10 million Americans with allergic asthma due to the urban heat island effect, which can elevate pollen production and worsen air pollution. Air pollution and pollen can pose a double threat because they can interact and become a more potent harm to asthmatic people. When ground level ozone pollution levels are high, it takes much less ragweed pollen to trigger an asthmatic or allergic response, according to a 2010 Asthma and Allergy Foundation of America report. In effect, the ozone primes the bronchial airways to be more sensitive to the allergen. A similar interaction occurs with diesel exhaust and pollen.
Not all parts of the U.S. are impacted equally by seasonal allergies — the Asthma and Allergy Foundation has created a list of cities in the U.S. that are most affected. The Foundation estimates an economic impact of $32 billion annually in direct health care costs and lost productivity, which could potentially rise as seasonal allergies worsen.
Additional resources
- American Academy of Allergies, Asthma and Immunology (AAAAI): A video of expert Jeffrey Demain discussing the climate change impact on allergic disease.
- National Ocean and Atmospheric Administration (NOAA): An article that points out that northern parts of the US will have longer growing seasons than the South and will have more pollen creation.
- National Public Radio (NPR): A radio segment that discusses how rising temperatures prolong pollen season and could worsen allergies.
- Google MapsP: A pollen API was added to maps where you can now view pollen as a layer.
- Cleveland Clinic: An article that has suggestions for how to reduce the impact of seasonal allergies by starting your medications ahead of time.
