A care home worker’s second positive Covid-19 test is likely to be linked to their original infection and not reinfection, NHS Highland has said.
The person is an employee at Skye’s Home Farm where 10 residents died amid a coronavirus outbreak at the home.
Local MP Ian Blackford has brought the case to public attention.
NHS Highland said “emerging evidence” suggested some people could have “intermittent negative and positive results over many weeks”.
HC-One, the home’s owners, said there had been no new Covid cases at Home Farm for 33 days, prior to the worker’s result on Sunday.
NHS Highland said precautions had been taken and the worker had been advised to remain at home and in isolation.
Their close contacts are being followed up by the contact tracing process and will be given the standard advice regarding isolation and effective hygiene.
All staff and residents are being re-tested as a further precaution.
Mr Blackford, the MP for Ross, Skye and Lochaber and the SNP’s leader at Westminster, said he had felt it important to make the public aware of the case, adding: “But I do acknowledge the work that is on going to deliver effective infection control at Home Farm.
“I am sure that all in the community will want to offer full support to the residents, their families and all staff at what has been a distressing time for all.”
NHS Highland said reinfection was not expected to be the cause.
A spokesman said: “Evidence is emerging internationally about Covid-19 and it is now recognised that some people have prolonged positive swab results and others can have intermittent negative and positive results over many weeks.
“An ongoing positive result does not therefore mean they are still infectious or that they pose a risk to others. This is the most likely scenario here.”
HC-One also said the second positive test was likely the result of the employee’s original infection and not due to a reinfection, adding that the risk of transmission was “very minimal”.
A spokeswoman said: “However, we are of course working closely with our local health and care partners and are taking all appropriate steps to respond to this.
“Testing is being made available to everyone who has entered the home recently and will be completed as a matter of urgency.”
NHS Highland is assisting HC-One with care provision at Home Farm.
The outbreak at the care home, which was detected at the end of April, was the first time the virus had been formally confirmed on Skye.
Last month, the Care Inspectorate took legal action over the running of the private care home.
The inspectorate asked the Sheriff Court to cancel the registration of the HC-One-owned Home Farm facility in Portree.
The move followed an unannounced inspection of the home.
The Care Inspectorate said the visit raised “serious and significant concerns” about the quality of care.
Court hearings held in May and earlier this month heard the joint working between HC-One and NHS Highland had led to improvements in care at Home Farm.