Allergy to Mold

Mold is a prevalent organism growing both indoors and outdoors. It is a type of fungus that breaks down dead material and returns nutrients to the environment. Mold digests plant or animal matter such as wood, paper, dirt, and food and spreads by releasing tiny spores into the air. Mold flourishes in dark, moist places. In particular mold will grow quick in basements, garbage cans, and piles of rotting leaves.

Everyone is exposed to mold on a daily basis with no ill effects. We may breathe in spores that have been released into the air or consume foods where mold has begun to grow. Those who have mold allergies, however, may have a negative reaction if exposed to too much of the fungus.

In addition to tree, grass, and weed pollens mold is a common cause of seasonal allergic rhinitis. People allergic to mold may experience allergic symptoms between spring and the late fall. Mold season most often peaks from July through late summer. Unlike pollens mold can persist after the first frost. Some molds can even grow at subfreezing temperatures, though, most become dormant. Snow cover in the winter reduces the outdoor mold count dramatically but doesn’t kill mold. After the spring thaw mold thrives on the vegetation killed by the winter cold.

In the warmest regions, however, mold can thrive all year round causing year-round allergy problems. Indoor mold even in the coldest climates can also cause perennial allergic rhinitis.

An allergic reaction to mold is most often a reaction to the mold spores. Mold spores are the seeds or reproductive particles of the fungus. Depending on the species they differ in size, shape, and color. When inhaled, the microscopic spores may cause allergic rhinitis.

Another source or mold allergy symptoms can come from eating certain foods. Cheeses processed with fungi are an example. In addition, mushrooms, dried fruits, and foods containing yeast, soy sauce, or vinegar may also produce such allergic symptoms.

Mold is found where there is moisture, oxygen, and a source of the few other chemicals they need to thrive. In most often found outdoor in moist shady areas such as rotting logs, fallen leaves, in gardens, compost piles, and on grains such as oats, barley, and corn, making farms, grain bins, and silos likely places to find mold. Inside the home mold is most often found in damp basements, closets, and bathrooms. Also, where fresh food is stored or refrigerator drip trays, house plants, air conditioners, humidifiers, garbage cans, mattresses, furniture and old foam rubber pillows are locations mold is often found.

Those who work in bakeries, breweries, barns, dairies, greenhouses are often exposed to mold. In addition those working with wood, such as loggers, mill workers, carpenters, furniture repairers, and upholsterers often work in moldy environments.

Mold spores, like pollens are important airborne allergens only if they are in abundance and easily distributed by air currents. Also while there are many types of molds only a few dozen different types are significant allergens. Alternaria and Cladosporium (Hormodendrum) are the types of mold most commonly found both indoors and outdoors throughout the United States. Also common are Aspergillus, Penicillium, Helminthosporium, Epicoccum, Fusarium, Mucor, Rhizopus, and Aureobasidium (Pullularia).

Fungi or microorganisms related to them may cause other health problems similar to allergic diseases. Some kinds of Aspergillus may cause several different illnesses, including both infections and allergy. These fungi may lodge in the airways or a distant part of the lung and grow until they form a compact sphere known as a “fungus ball.” In people with lung damage or serious underlying illnesses, Aspergillus may grasp the opportunity to invade the lungs or the whole body. In some individuals, exposure to these fungi also can lead to asthma or to a lung disease resembling severe inflammatory asthma called allergic bronchopulmonary aspergillosis. This latter condition, which occurs only in a minority of people with asthma, is characterized by wheezing, low-grade fever, and coughing up of brown-flecked masses or mucus plugs. Skin testing, blood tests, X-rays, and examination of the sputum for fungi can help establish the diagnosis. Corticosteroid drugs are usually effective in treating this reaction; immunotherapy (allergy shots) is not helpful.