The Surprising (or Not So Surprising) Cause of Increased Fall Allergy Suffering

While many of us look forward to the harvest season, cooler weather, and the start of the holidays, fall is one of the most impactful and detrimental times for allergy sufferers. While trees, grasses, dust mites, mold, and dander can impact allergy patients year-round, weeds are implicated in the spike in symptoms from late summer through the fall - and there is a surprising (or not so surprising) cause of increased suffering this season.

In recent years weeds have been pollinating earlier due to elevated carbon dioxide (CO2) emissions. Elevated CO2 causes the earth's temperatures to rise, and the warming of the earth fuels growth in allergens like ragweed, causing them to pollinate earlier and stay in season longer. 

"Global warming affects the onset, duration, and intensity of the pollen season as well as the allergenicity of the pollen. Studies on plant responses to elevated atmospheric levels of CO2 indicate that many weeds exhibit enhanced photosynthesis and reproductive effects and produce more allergenic pollen adding to many patients' allergy misery. Increased CO2 acts as “fertilizer” for plant growth. The fertilizing effects of carbon dioxide and increased temperatures from climate change increase pollen production. Changes in atmospheric circulation shift allergens to new geographical regions and introduce individuals to allergens that have not been exposed previously. These influences can exacerbate asthma or other respiratory illnesses.” (1)

"Climate change is scientifically unequivocal and represents a possible threat for patients affected by allergic conditions... Data suggest an increasing effect of aeroallergens on allergic patients over this period, implying a greater likelihood of developing an allergic disease in sensitized subjects and exacerbating symptomatic patients." (2)

While avoidance of allergen triggers is a standard recommendation from providers to patients, and unfortunately, it's safe to assume that seasonal allergies and climate change will not reverse in our lifetimes, allergen immunotherapy is the only option to desensitize the overactive immune system long-term and that’s where AllergiEnd® steps in, we can help your patients desensitize against this pervasive disease. 

Many common allergens this season are blooming earlier and lasting longer, causing what feels like never-ending suffering for many patients.

Common fall allergens include the following and may be impacting your patients:

• Ragweeds are flowering plants native to North America and Mexico but can also flower in late summer and fall and are responsible for both the majority and the most severe cases of allergic rhinitis. Ragweed pollen also contributes significantly to the exacerbation of asthma and allergic conjunctivitis. Ragweed, particularly "common ragweed," is responsible for the most severe seasonal allergic rhinitis or hay fever cases. (3)

• Mugwort is native to Europe, Asia, northern Africa, and Alaska. It has been introduced into the eastern United States and resembles ragweed in its juvenile form, blooming in the late summer and early fall. (4) Foods that cross-react with the mugwort pollen include hazelnuts, apples, melons, watermelons, kiwi fruit, celery, carrots, caraway seeds, parsley, coriander, anise seeds, fennel seeds, and peanuts. The protein that cross-reacts with the pollen changes with heat, so cooked fruits and vegetables do not typically cause the symptoms of oral itching. For example, soups and sauces that contain these vegetables can often be eaten without symptoms. Mugwort pollen is a significant cause of asthma, allergic rhinitis, and allergic conjunctivitis. Mugwort pollen contributes to Oral Allergy Syndrome (OAS), eczema, urticaria, and anaphylaxis where pollen has contaminated a food. (5)

• Rough marsh-elder is an annual weed often mistaken for ragweed, and flowering occurs from July to October. All species are wind-pollinated and shed large quantities of pollen. Marsh-elder grows in moist habitats near ponds, lakes, fallow fields, wet prairies, roadsides, and disturbed areas. The pollen may cause severe hay fever (allergic rhinitis), asthma, and allergic conjunctivitis. Contact with the leaves may produce a skin rash in some people. (6)

• Cockleburr (Xanthium) is native to Europe, Asia, and southern Canada but is now found worldwide. Cocklebur flowers from summer to late autumn, usually July to October, with seeds ripening from August to October. This weed is commonly found in cultivated fields, waste areas, run-down and abandoned pastures, road ditches, and fields. (7) The burrs often become tangled in the fur of grazing animals, thus aiding the distribution of the species. Both seeds and seedlings are toxic to livestock. Evidence suggests that asthma, allergic rhinitis, contact dermatitis, and conjunctivitis occur following pollen exposure from cocklebur. (8)

• Kochia is a significant pollen source and was introduced as a garden ornamental in Asia in the early 1900s. This weedy annual spread state by state, and by 1980, it had reached eastern Washington. Kochia is very drought tolerant and can invade both irrigated and dryland crops. Kochia flowers in mid to late summer, but the timing is highly variable. Kochia becomes a tumbleweed when it matures, affecting crop production in many parts of the world. It is drought tolerant and grows abundantly in pastures, rangelands, roadside areas, ditch banks, wastelands, and cultivated fields. (9) Kochia pollen causes asthma, hay fever, and allergic rhinitis. (10)

While avoidance is the first line of defense for allergy triggers, the severity and duration of seasonal allergies continue to grow as the earth continues the warming pattern. Patients often improperly medicate with over-the-counter medications, merely masking the symptoms temporarily. A permanent problem requires a permanent solution, which means addressing your patient's allergies at the root cause. AllergiEnd® offers the assessment, testing, and immunotherapy treatment needed to improve clinical outcomes and provide your patients with the lasting relief they need.

Sources:

1. Mendelson, MD, A., Smollar, M., & Grogan, T. (n.d.). Environmental Allergic Disease Desensitization in the Primary Care Setting. 

2. Cecchi L, D’Amato G, Ayres JG, Galan C, Forastiere F, Forsberg B, Gerritsen J, Nunes C, Behrendt H, Akdis C, Dahl R, Annesi-Maesano I. Projections of the effects of climate change on allergic asthma: the contribution of aerobiology. Allergy 2010; 65: 1073–1081.

3. http://www.phadia.com/fr/5/Produits/ImmunoCAP-Allergens/Weed-Pollens/Allergens/Common-ragweed/

4. http://www.pollenlibrary.com/Specie/Artemisia+vulgaris/

5. http://allergies.knoji.com/mugwort-allergy/

6. Yman L. Botanical relations and immunological cross-reactions in pollen allergy. 2nd ed. Pharmacia Diagnostics AB. Uppsala. Sweden. 1982: ISBN 91-970475-09.

7. http:// http://ainotes.wikispaces.com/file/view/Allergen+Cross+Reactivity+Table.pdf

8. Nandakishore T, Pasricha JS. Pattern of cross-sensitivity between four Compositae plants, Parthenium hysterophorus, Xanthium
   strumarium, Helianthus annuus and Chrysanthemum coronarium in Indian patients. Contact Dermatitis 1994;30(3):162-7.

9. www.plants.usda.gov/plantguide/pdf/pg_basc5.pdf

10. www.allallergy.net/fapaidfind.cfm?cdeoc=595