More than 26 million Americans have asthma. Of our friends, colleagues and family members who are living with asthma, 5-10 percent of them have severe or difficult to control asthma and experience asthma symptoms more frequently. Asthma triggers - such as cigarette smoke and air pollution - can cause asthma symptoms. For people who have allergic asthma, things like pollen, animal dander, and certain foods are common causes of asthma worsening. Frequent among these triggers for persons with allergic asthma are molds.

The Mold and Fungus in the Air We Breathe

Fungus can live and grow everywhere. When we hear about fungus we often think about "the dark stains" found on our bathroom walls and ceilings or on expired foods. Some fungi are good for us, others are not so helpful. Fungi in the form of yeast allow us to make wine, beer and cheese and are among our most potent allies in the war against infections such as penicillin.

Mold, a microscopic organism, is a common type of fungus that can be invisible, float in the air and inhaled causing respiratory problems. As mold moves through the air it can attach itself to your clothing, shoes, bags and pets. Mold can also blow into your home through open doors, windows, vents as well as heating and air conditioning systems. When mold is inhaled by people who are allergic it can cause asthma and other allergy symptoms.

How Does Mold Affect My Asthma?

According to Amit Parulekar, M.D., an assistant professor at Baylor College of Medicine and American Lung Association clinical patient care research grantee, people with asthma who are allergic to mold tend to have reduced lung function, increased hospital visits and may even die from asthma-related illnesses. When mold is inhaled, particularly by persons with allergies, mold spores can be perceived as a danger to the immune system and cause an allergic reaction. The airways may constrict, produce more mucus and become red and swollen. This reaction in the airways causes people to experience chest tightness, shortness of breath, wheezing or coughing. However, people who are allergic to molds should be reassured that there are ways to limit exposure and new emerging ways to diagnose and treat allergic asthma caused by molds.

How to Limit Exposure to Mold

When mold is a trigger for people with asthma, it may be difficult to eliminate their exposure. Dr. Parulekar shares that when working with patients, he considers their medical history and counsels patients to modify their home environment. Patients can limit their exposure to mold or fungi by:

  • Using an air conditioner or dehumidifier and a humidity monitor that shows the humidity levels in the home. It's important to keep levels below 50 percent.
  • Ensuring that there is proper ventilation by including exhaust fans in the home.
  • Cleaning bathrooms and other potentially moldy areas with asthma-friendly, mold-killing products.
  • Avoiding the outdoors on days when mold counts are high
  • Wearing a mask if you must be outside.
  • If possible, eliminating the source of mold, by locating and repairing moisture sources and getting rid of existing mold contamination by home remediation

Current Research on Mold and Severe Asthma

Dr. Parulekar is currently researching the effect of mold and other fungi in the lungs of patients with severe asthma. The goal of his research is to validate the association between mold and other fungi and worse asthma outcomes. Through a clinical trial, Dr. Parulekar hopes to impact the treatment of patients with asthma by more accurately identifying patients who are allergic to mold and other fungi and the role they play in managing asthma. As part of Dr. Parulekar's study, he is using new techniques to determine the presence of mold and other fungi in the airways, which in turn may help to identify patients that might benefit from anti-fungal treatments. As a result, patients with a mold or other fungal trigger may be treated with therapies that target molds or other fungi resulting in improved asthma management.

Although asthma is a life-long disease it can be treated and managed, allowing an active and healthy life. The American Lung Association has resources available to help you reduce exposure to asthma triggers. You can also connect with and learn from others living with asthma through our online support community. For more information and resources on asthma and mold call the Lung HelpLine at 1-800-LUNGUSA (1-800-586-4872).

Asthma Educator Institute
, | Jul 11, 2015