CalMac has confirmed that a fourth crew member from MV Isle of Lewis has tested positive for coronavirus.

Last week the shipping company confirmed that the service had been cancelled so that it could undergo a "deep clean" when three crew tested positive.

READ MORE: CalMac ferry cancellation amid new outbreak in Western Isles

None of the four employees developed symptoms while working on the ship, and NHS Western Isles are working with CalMac to carry out test and protect.

One individual is currently isolating in Lewis while the two are self-isolating outwith the Western Isles.

It is understood that the fourth case of Covid-19 is not from the Western Isles, where the small cluster remains at only three cases.

The vessel sailed without passengers to Oban where it received a deep clean on Sunday.

Robert Morrison, operations director for Cal Mac, has said “strict procedures” have been followed.

He said: "Cal Mac crew work in strict bubbles in order to protect passengers and colleagues but anyone concerned about potential symptoms should check the NHS Inform website.”

Meanwhile, Gordon Jamieson, NHS Western Isles chief executive said a “significant” number of people have been identified as close contacts and asked to self-isolate.

Speaking in a video posted to Twitter, he said: “I can reassure you that all those people for whom we have details who were identified as close contacts have been contacted and are now in isolation.

“A significant number of people are now in 14 days isolation.”

He reiterated the urgency of booking a test immediately and self-isolate if anyone develops symptoms.