The importance of Alternaria mold exposure to allergic disease is underrecognized in urban communities compared to dust mites, cockroach and mouse exposure. Concentrations of Alternaria mold are higher in outdoor than in indoor air, however dampness, leaks can cause fungal penetration and growth indoors. Given the amount of time people spend indoors, indoor exposure may contribute more than outdoor exposure to asthma.
A recent study looked into to see if sensitization to Alternaria alternata mold would be associated with increased asthma symptoms. Alternaria mold was detected in 85% of homes ranging from 10-33,000 mold spores in NYC homes. The concentrations of Alternaria mold was associated with rates of asthma. Allergy to Alternaria mold was detected in 16% of children.
The summary of the study concluded that Alternaria alternata mold appears to be relevant to asthma morbidity for children living in New York City. Alternaria mold was detected in most homes, suggesting domestic exposure is common. Alternaria alternata was associated with increased asthma markers.
There are many allergy factors that can contribute to worsening asthma. Most people know about pet dander allergy, many homes have cats and dogs in them which can cause worsening allergies and asthma for those who are allergic to them. In inner city homes, mouse and rat droppings have become a significant trigger for children who have asthma. Dust mites and cockroaches have been well known over many years as provocative factor in worsening asthma. This most recent study shows although many people think of Alternaria mold as an outdoor allergy trigger, it is indeed prevalent in many homes. This can cause worsening asthma and allergy symptoms and it needs to be tested for and considered in those who have symptoms at home.
Alternaria alternata allergy can be tested for by an allergist along with other common indoor and outdoor molds.