Is it likely for an adult to suddenly develop cough variant asthma?

Cough . Persistent cough can be due to sinus infections, asthma, smoking, lung infection or disease and GERD. If your cough has lasted more than 2-3 weeks whether persistent or intermittent you really need to see your doctor and go through the list of possibilities for you. A cough is a mechanical way for the body to eliminate mucous from the lung which is normally migrates out without any effort. .