Other people who are susceptible (besides those with Bronchiectasis) include people with other lung diseases such as Cystic Fibrosis and Emphysema, people with compromised immune systems, and in some cases, people who have had lung surgery.

Airway clearance helps eject the mucus (and the germs it contains) from our compromised lungs to prevent colonies from growing. Normal lungs are able to do this with routine coughing and throat clearing. For me, it is the most important part of staying healthy.
Sue