Mold is a fungus that comes in thousands of varieties and grows both outside and inside. In order to thrive. mold needs two things: water and warmth -- and you certainly don't have to endure a hurricane to find it multiplying in your home. "Mold spores are everywhere. They're just waiting to be watered to start growing," says Paul J. Pearce, PhD, assistant professor of pathology and microbiology at Baylor College of Medicine in Houston. Mold can be present indoors during the entire year. And in most of the country, this is the time when outdoor molds start to grow as well. They flourish in damp, shady areas such as piles of leaves, hay, grass, and soil, and they last through late fall. In warmer climates, they can be a year-round problem.
Up to one-third of children are allergic to mold (only pollen allergy is more common). Inhaling spores -- the invisible airborne seeds of mold -- can cause sneezing, a runny nose, itchy eyes, wheezing, and coughing. If one parent has allergies, a child has a 30 to 40 percent chance of inheriting the tendency to develop them; if both parents are allergic, the odds are more than 50 percent. Unfortunately, doctors are finding that mold allergy is more than just hereditary. A study at the University of Cincinnati revealed that babies exposed to high levels of certain types of household molds have an increased chance of developing multiple allergies later in life. Other research has found that children who live in a home with visible mold and a history of water damage have as much as double the rate of asthma -- even if their parents don't suffer from the disease. Asthma and mold are a particularly risky combination. Most kids with asthma are allergic to mold, and they tend to react more severely to molds than they do to other triggers. "Outdoor mold begins growing in the spring and gets worse as the year progresses," says Linda B. Ford, MD, an allergist at The Asthma & Allergy Center in Omaha. "If your child has asthma, it's important to try to avoid places that are most likely to have mold." Areas that are especially mold-prone typically include home vegetable gardens, freshly mowed grass, barns, farms, and buildings closed during the winter.