Are asthma sufferers more at risk of life threatening complications from the coronavirus?

The preventer should be used as directed, otherwise it is not preventing anything is it? he may be quite ill if he gets the virus, start giving him his medication properly.

Generally speaking, anyone with lung problems is at a higher risk of complications from a respiratory infection. Mild asthma in an otherwise healthy child is less of a risk than end stage COPD in an 80 year old with diabetes and heart disease. If you want to know specifically what, if any, increased risks your son has, you need to talk with his doctor. I’m not sure what his “preventer” inhaler is, but inhalers don’t reduce the risk of getting a respiratory infection.

So far it mostly seems to be those with compromised immune systems and chronic lung diseases like COPD that are at greatest risk. It also does not seem to be especially severe in children (as compared to flu, for example). If he does not have any symptoms and his peak flow meter is still in the green range (you do have a PFM, yes?), there is no reason to do anything. His inhaler does not change his risk of infection. There's nothing to do at the moment outside of the same things you would do to prevent flu or RSV -- wash your hands, avoid congested public places, and if he does show respiratory symptoms, have him seen by the doc that manages his asthma. 

Relax already good grief

Anyone with lung problems or a compromised immune system are at greater risk.