Listening to someone on TV the other day, it's more to do with general health than age. Someone phoned in who was well into their 70s and ran four miles each day (or whatever) and asked whether the advice given to the over 60s about self isolating really applied to him. The expert after a bit of waffle brought the advice to a swift conclusion by basically saying it didn't and that it was really all about general health. (So maybe we should go by BMI as well as age.) My views are largely formed by a stat mentioned on the radio when the death count was around 13000 (before deaths in care homes were being counted) when it was said that only 11 of those deaths were to people under the age of 45 with no underlying health issues. 9 men and 2 women. Think lions and wildebeest. ETA From a survey of 16749 people with Covid-19 admitted to 166 UK hospitals, the median age was 72 and the interquartile range was 57-82.