coronavirus at a Scots nursery has raised concerns about a full return of youngsters to the classroom.It is understood a community cluster was linked to asymptomatic youngsters at the Mulberry Bush Nursery in Helensburgh.The nursery had been allowed to remain open during the lockdown for children of frontline workers.But several families in the town were forced to self isolate after the outbreak was discovered.Fraser Murdoch, owner of the nursery, in the town’s Charlotte Street, refused to speak