Actually, there is something about jimmyT's post that I think needs picking up. I learned it during the period that my late wife was breathing impaired. She later died from her emphysema, plus a chest infection, plus the incompetence of Medway Maritime hospital.

But for years she managed her breathing problems well, and worked.

If she had caught a respiratory infection from even a commuter - and heaven forfend that she should risk infection from a health professional (a dentist, say) who was supposed to be treating her, that would have made her very ill and could have killed her.

People like jimmyT, who work with "a runny nose" and twist their employees arms to work when they too are infectious are possible killers. Don't do it.