Coronavirus: Contact tracing like 'detective work'

Trish Mannes, leader of the health protection team for Public Health England South East, says they've "never attempted anything on this scale before" with the introduction of the Test and Trace app but thinks it "will work".

In an interview with the BBC's Hugh Pym, she explains the process of contact tracing, saying the process of finding people who may have been exposed to coronavirus is a bit like detective work.