Tis The Season: Winter Allergies

10/27/2020

Tis The Season: Winter Allergies

By Dr. Irum Noor

Allergy season is not only present in the spring and fall! Pollen allergies are most prevalent in the spring and fall but let’s not forget we can be allergic to indoor allergens such as molds, pet dander, and dust mites. Why might we have allergy symptoms throughout the winter and what can we do to get ahead?

Dust mites are 8 legged arthropods that live in the house dust of homes located in regions where they are prevalent.¹ Mites thrive in humid environments and are most prevalent in our bedrooms, especially in our mattresses and bedding. When the fecal particles of dust mites become airborne, dust-mite allergic patients can suffer from symptoms of allergies year-round. Mites have decreased survival and reproduction with relative humidity below 50%, therefore it is recommended that dust-mite allergic patients use a hygrometer and maintain humidity between 35% and 50% to decrease growth of dust mites. Another recommended intervention is using mite allergen proof mattress, box spring, and pillow encasings to decrease exposure to mite allergens. Regular vacuuming using cleaners that have high-efficiency particulate air (HEPA) filtration or with a central vacuum with adequate filtration or that vents to the outside to decrease exposure to dust mite allergen-containing particles has also proven to be beneficial.

Our furry friends, particularly cats and dogs, are a huge cause of allergy symptoms in the winter for those patients that are allergic. Both cats and dogs have a number of identified allergens with a variety of biologic and immunologic properties.  These allergens are present in the indoor environment of homes, workplaces, and schools regardless of whether the animal is residing there or not. If animals cannot be removed from the environment to reduce allergen exposure, it is recommended that they are kept out of the bedroom. Carpeting and bedding are significant reservoirs of allergens, frequent vacuuming or ideally carpet removal should be considered.²

Indoor molds are another cause of allergies in the winter. Mold thrives in damp, humid environments such as basements and bathroom. Specific outdoor molds such as Cladosporium that are very prevalent outdoors can also be brought indoors. Some outdoor molds are more present in the late Summer through Fall. It is important to be cognizant of activities such as raking leaves increasing exposure to mold spores. Using potent cleaners in the bathroom such as Clorox and Lysol can be beneficial to prevent mold growth.

As the temperature drops, we are all reaching to turn the heat on. Before turning on the heat, it is important to make sure that the vents have been cleaned. Dust mites, mold spores, and pet dander can all travel in the air once the heat is kicked on. During the winter holidays we can be ahead with decreasing allergen burden by considering an artificial Christmas tree, washing dust off of ornaments before hanging, as well as considering glass/plastic ornaments instead of fabric. While visiting the homes of loved ones this holiday season consider bringing allergy medication as well as your own pillow!

If you are experiencing symptoms of allergies such as coughing, itchy eyes/nose, runny nose, sneezing, watery eyes, etc. for more than a week, it is a good idea to visit an allergist. An allergist will be able to perform a skin prick test to confirm clinical sensitivity induced by aeroallergens. Based on test results, various treatment options including antihistamines, intranasal steroids, decongestants, or immunotherapy (allergy shots or sublingual tablets) may be offered.

1. J. Portnoy et al. Environmental assessment and exposure control of dust mites: a practice parameter. Ann Allergy Asthma Immunol 111 (2013) 465e507466
2. J. Portnoy et al. Environmental assessment and exposure control: a practice parameter – furry animals. Ann Allergy Asthma Immunol 108 (2012) 223.e1–223.e15223