This article in the NYTimes about Covid Pneumonia got me thinking about the role of Pranayama as an early diagnostic tool to alert you of breathing issues caused by the virus.
Unlike standard pneumonia, the particular kind of pneumonia caused by Covid-19 does not make one feel short of breath until much later in the illness, when it could be too late. Your lung capacity could be reduced by 20% but you may not have the usual symptom of shortness of breath. This means so you could be going about your normal activities without noticing anything abnormal. If you happen to have a daily pranayama practice with 20 second breath retentions (for example), then you should notice straight away that something is off. What would usually feel like a normal retention suddenly will become very hard or impossible to achieve.
If this happens, as per the article, check your blood oxygenation levels using a Pulse oximeter. And if the levels are abnormally low contact your healthcare provider.