Alternaria is one of the most common airborne funguses. Found indoors and out, it is typically the fungus most prevalent in the daily “pollen count” done by this office.
It has been known for many years to be a major contributor to respiratory allergy, both upper airway (rhinitis) and lower airway (asthma).
New research done by the National Heart and Lung Institute in the U.K. has revealed a second mechanism whereby it causes respiratory mischief. In addition to its “allergenic irritability,” Alternaria wreaks further havoc because it prompts protease-activated receptors found in human airwaves to release the inflammatory molecule IL-33 (interleukin-33). IL-33 is an extremely vitriolic molecule and causes both airway inflammation and airway remodeling (scarring).
Epidemiologic studies have found a strong correlation between environmental Alternaria levels and hospital admissions for asthma.
In some studies it is believed to cause 30 percent of asthma exacerbations.
The thunderstorms of summer and fall lead to dispersion of Alternaria spores, plus all molds tend to be higher in autumn.
The British researchers are looking at ways to try to abrogate the IL-33 release.