Why is asthma so common?

A combination of factors contributes to the persistent prevalence of asthma in many communities across the nation, where asthma remains the number one reason children are absent from school and the number one reason they are hospitalized. Homes contain high-risk asthma triggers. Dust, mold, rodents, and smoking are primary triggers for asthma exacerbations and can be mitigated. Seasonal allergens, air pollution, and weather can also trigger an asthma episode.