They have a post up on facebook explaining. Apparently it was all set up, people had already travelled, when they cancelled in 2018 they found hundreds of people still ran and they would rather people ran with support from the organisers.As far as I know, a snotty nose isn't a symptom but a common cold for which the advice is isolate for 7 days as opposed to 14
I wonder why when the London marathon has been postponed till October?
Also they dont use the police or ambulance service, they have their own private teams to help. Although if anything happened to someone you can sure as hell bet they would end up getting treatment from an nhs hospital!