Hugh Pennington, emeritus professor of bacteriology at Aberdeen University, said carers should be tested a minimum twice a week to cut the risk of the virus getting into care homes.
It comes as The Scotsman learned staff in a number of Scottish care homes have been opting out of routine tests with managers unable to enforce because it is not a requirement by law.
Professor of public health at Edinburgh University, Linda Bauld, also said repeat testing of staff is an important part of reducing the risk to elderly and believes it should be required, but handled sensitively and the needs of employees taken into account.
A Scottish Government spokesperson said they “strongly encourage” all care home staff to take part in routine testing and that funding is in place to ensure social care workers do not experience financial hardship due to self-isolating.
The spokesperson also said they are working closely with local public health, unions and care homes to understand why staff refuse and try to address concerns - but they stressed uptake of routine testing is “very high” on a weekly basis with more than 37,000 care workers being tested in Scotland for the sixth consecutive week.
Professor Pennington said: “Protecting care home residents, who as a group are the most vulnerable in terms of dying from Covid, must get top priority.
“By far the best and most effective way to do this is to make sure that anyone going into them and staying inside for more than 20 minutes has had a negative test, if possible on the day of their visit. Turn round times make this difficult.
“My view is that as a minimum all staff must be tested twice weekly. This should be mandatory. We don't yet know whether virus transmissibility will increase in winter, but it is reasonable to factor such an increase into policy making. I hope that care homes themselves are making plans for winter staff shortages.”
‘It should be required’
Scotland’s care homes were hit by a wave of coronavirus soon after it arrived in the UK earlier this year, with registered deaths in care homes now making up nearly half of the death toll.
Covid-19 transmission has also been rising in recent weeks across the spectrum of age ranges.
According to the Scottish Government website, 92 adult care homes - 9 percent - had a current case of suspected Covid-19 as of September 30 and, in the week up to September 27, there were 32 new confirmed positive coronavirus cases among care home residents.
Professor Bauld said: “Repeat testing of care home workers, and where appropriate, NHS staff, is an important element of reducing the risk that older and more vulnerable adults will be exposed to the virus and become unwell. This is an approach that is being widely used in other countries now, so not unique to Scotland or the UK.
“It would be concerning if staff were declining these tests and if that is the case, the reasons for it need to be investigated and addressed. My own view is that it should be required, but handled sensitively and the needs of staff listened to and taken into account.”
The Scottish Government spokesperson added: “Regular testing of people who do not have symptoms has a key role to play in protecting the vulnerable and preventing outbreaks in high risk settings.
“Currently this testing is offered to care home staff, and staff working in certain parts of the NHS, like long stay old age psychiatry and learning disability wards. In addition, anyone with symptoms can access a test through our test sites or by ordering a home test kit.
“Our approach to testing, including prioritisation, is flexible and adaptable to the prevailing conditions of the pandemic. We are constantly keeping our Testing Policy under review so that it is up to date with scientific and clinical advice.”
A spokesperson for the Care Inspectorate said: "Guidance and rules on testing for Covid-19 are a matter for the Scottish Government and everyone should follow the guidance and rules in order to keep people safe.”