[RobertG (OP)]

Maybe a bit of a naive question. Whilst trying to learn to sing, I was told to inhale though the nose, and exhale through the mouth. Does inhaling through the nose help to stop the virus from  getting into the lungs?

[chris]

Inhaling through the nose definitely helps to "filter", pre-warm and moisten inhaled air, but this might not actually be advantageous in the case of Covid-19: new research has shown that there are specific cells in the nose that are susceptible to infection by the virus owing to the expression of the right combination of the ACE2 entry receptor and and a protease required to prime the viral spike protein.

This observation also accounts for the loss of smell and taste sensations reported by some patients.

https://www.thenakedscientists.com/articles/science-news/why-covid-19-causes-loss-smell-and-taste