Covid cases on Barra have almost tripled in the last 24 hours.
17 new cases were recorded on the island yesterday, meaning 27 positive tests are now linked with the outbreak there.
Tests are still ongoing for Barra, with some going through the system and some being carried out today.
More than 110 close contacts have been identified and they are currently self-isolating.
NHS Western Isles Chief Executive Gordon Jamieson described the situation as “serious” in his daily Covid update.
He said: “This outbreak and the number of people affected, with 110 now in self-isolation, represents a significant proportion of the population on Barra and this is an escalating and serious situation.
“We must suppress and contain this virus as quickly as possible.
“Please limit your household contact and take every precaution you can to protect yourself and your community.
“If you develop any symptoms, then please self-isolate and arrange a test immediately.”
Anyone who has been identified as a close contact to any of the people with Covid-19 on Barra is being offered a test, as efforts to clamp down on the spread intensify.
The population of the island is just over 1000, meaning about 10% of Barra is currently self-isolating.
National clinical director Jason Leitch claimed at Friday’s Covid briefing that the outbreak on the islands was “believed to be under control.”
This was due to no positive cases on the Western Isles being recorded on Thursday.
He said the islands are “not seeing sustained community transmission”.
