Other allergens, while less repugnant, are being found to cause equally serious problems. For example, it has long been known that the spores of certain fungi--particularly the types commonly known as molds--can trigger allergic reactions. But just how prevalent such problems may be is only now becoming clear.
In 1989 the American Academy of Allergy and immunology (AAAI) improved its national network for monitoring airborne allergens by implementing more sophisticated methods for taking pollen counts. The results were a surprise to many. "Fungus spores [mold's seeds] everywhere were much higher than anyone expected," says Harriet Burge, Ph.D., the University of Michigan Medical School microbiologist who heads the effort. Jean Chapman, M.D., a Cape Girardeau, Missouri, allergist who chairs the AAAI's aerobiology committee with Burge, calls spores "the most important allergens I deal with."
Now allergists have a whole new group of fungal allergens to worry about: basidiospores. Basidiomycetes are the class of fungi that includes mushrooms and puffballs. Their spores were first implicated as a cause of asthma in New Orleans 30 years ago, but most allergists considered them a problem exclusive to hot, steamy climates. Only in the last few years has Samuel Lehrer, Ph.D., a professor at Tulane Medical School, proved them wrong. In a 1989 study of more than 400 asthma and hay fever sufferers in seven cities, he found that 23 percent were sensitive to basidiospores--almost as many responded to other, well-known mold allergens. Surprisingly, the highest response was not in New Orleans, as Lehrer had expected, but in Seattle, where a whopping 44 percent of the patients tested were allergic. Even in frigid Rochester, Minnesota, 13 percent of subjects had reactions. "The point is that basidiospores appear to be an important allergen throughout the United States," says Lehrer. While basidiospores are usually found outside, it's reasonable to assume that they can also come indoors, he says, unless houses are kept air-tight. Other indoor molds thrive in damp places like basements and bathrooms.
Fungus allergies are among the most frustrating for allergists to deal with. Mold spores can be in the air virtually year-round. Unfortunately, spores of different species are sometimes hard to tell apart, so even when an allergist knows a fungus is causing a reaction, an air sample won't always reveal exactly which fungus. For many fungus allergies, doctors can do no more than prescribe symptom-relieving drugs and advise patients on how to avoid the allergen. If indoor fungi seem to be the problem, scour the shower frequently to remove mold, avoid damp basements, keep humidity below 50 percent and clean dehumidifiers regularly.
As work progresses in discovering causes of indoor allergies and finding ways to combat them, sufferers may be able to look forward to a day when the yucky, slimy triggers will be merely disgusting, not wreakers of respiratory havoc.
Be sure to also see the page on dust mites, which also cause allergies. Control measures include enclosing the mattress top and sides with a plastic cover or other dust mite impervious cover (available here), thoroughly vacuuming mattress pillows and the base of the bed. Put an airtight plastic or polyurethane cover over your mattress. This tip is number one for a reason: it is in your bed that you are closest to the mites and their feces and enclosing the mattress and pillows in a dust mite cover virtually eliminates the mites here. There is a website, The Allergy Store, that we recommend that sells allergy controls, like the dustmite-proof fitted sheets. Mattresses covered with "fitted sheets" help prevent the accumulation of human skin scales on the surface