About Asthma, April 12, 2007 Could asthma be caused by germs, rather than the more commonly accepted triggers such as pollen, mold, dust, pet dander, and tobacco smoke? It's definitely possible. Conventional medical wisdom is that asthma usually has an allergic basis and that medicines such as inhaled steroids are most effective in treating it. However, it's also true that some people who have asthma do NOT seem to have allergic triggers, nor do they respond very well to inhaled steroids. Researchers believe this may be because-at least for those people-asthma may be related more to an infectious organism.  So, a new National Institutes of Health research study being conducted at The University of Texas Medical Branch at Galveston (among other places throughout the US) will study the effectiveness of an antibiotic called clarithromycin in controlling asthma symptoms. They are currently recruiting participants.