However, in May, P&O Cruises said that only 0.64 per cent of passengers were symptomatic on Wednesday 22 May, but failed to confirm how many suffered at the virus’ peak.

P&O Cruises confirmed to the BBC that the illness was norovirus. Earlier on Wednesday, a spokeswoman reported there were "currently 0.64% symptomatic on-board Ventura".

However, in May, P&O Cruises said that only 0.64 per cent of passengers were symptomatic on Wednesday 22 May, but failed to confirm how many suffered at the virus’ peak.