The impact of coronavirus on Oldham schools has been laid bare as leaders reveal that on any given day more than 4,000 pupils are having to self-isolate.Schools and educational establishments are due to remain open throughout the four week lockdown in England beginning on November 5.However at a meeting of Oldham's full council, bosses outlined how the virus was already having a significant effect on schools in the borough.Under government rules, 'bubbles' in schools have to self-isolate if