What is Asthma? How does it progress? Asthma is a chronic lung disease characterised by blockage of the airways. If left untreated, breathing problems may increase, which negatively affects daily life. Asthma can show symptoms that vary from individual to individual depending on the triggers and can become severe when left uncontrolled. Asthma Symptoms Symptoms of asthma in the early and advanced stages include wheezing, rapid breathing, speech [...].