Case numbers reached a new record on Thursday, with 4,234 reported, while latest figures show the overwhelmed Test and Protect contact tracing service is reaching less than a third of people who test positive within 24 hours.
The number of people in hospital has risen to 275, while 16 are in intensive care. Six deaths within 28 days of a positive Covid test were also reported on Thursday – the highest number since April 1.
Health boards have pleaded with residents to get tested and isolate if needed, amid rising pressure on services.
NHS Tayside saw the number of Covid hospital patients increase from 20 to 36 between Wednesday and Thursday.
Dr Pamela Johnston, NHS Tayside Operational Medical Director, urged people to follow Covid-19 rules.
“We currently have 36 patients in hospital requiring care for Covid with some of those requiring more intensive care in our ICU and HDU,” she said.
"Many of these patients are under the age of 40 and we expect this number to increase over the next few weeks.”
The increase in case numbers, along with staff self-isolating and more emergency activity and surgeries, had led to increased pressure on the health board, Dr Johnston said.
She added: “I know everyone is really fed up of living with restrictions and wants to enjoy the summer, but we really need your support to get the number of new cases down."
The BMA Scotland union said services were becoming more vulnerable and the workforce more stretched.
Commenting on the increasing number of staff absences due to Covid, Dr Lewis Morrison, Chair of BMA Scotland said: “This is clearly a worrying trend, and to some degree inevitable given the rising number of cases in the community.
"It reflects the experience members are increasingly reporting to us and is a concerning reminder, both of how stretched our health workforce is and how vulnerable services are right now.
"While the wellbeing of staff off sick is of course a priority, every single person who is off leaves a gap which must be covered by already over-worked and in many cases exhausted colleagues.
"We didn’t have enough doctors before Covid and these rising levels of sickness will only make that substantially worse.”
Julie Lamberth, chair of the Scotland Board of nursing union the Royal College of Nursing, said: “Nursing staff across Scotland’s health and social care services have been working under the pressure of staff shortages for years now. Yet again these are being compounded by the increase in Covid related absences.
“We’re seeing the toll this is taking on staff who are already exhausted and worn down. Urgent action is required to ensure Scotland has the nursing workforce it needs to keep patients safe.”
Scottish Labour’s Health spokesperson Jackie Baillie called the staff isolation figures “alarming”.
“This alarming increase in staff absences is a reminder that we can’t let Covid spiral out of control,” she said.
“Having thousands of staff off every week is bound to take its toll on services. If cases continue to climb the pressure on the NHS will only grow.
“We need to get the virus back under control, but test and protect is at breaking point and the vaccine roll-out is slowing.
“We need to fix these problems urgently, and ensure that the NHS has the staffing capacity it needs to cope with any absences.”
Ms Baillie also criticised the Test and Protect system, which has come under strain recently amid high case numbers.
“Test and protect is collapsing under the pressure as cases spiral, and things will only get worse if we don’t fix this,” she said.
National Clinical Director Jason Leitch said recent strains on Test and Protect, which have led to delays in people being contacted within 24 hours of encountering a positive case, “potentially does lead to a bigger spread of the virus”.
Liberal Democrat leader Willie Rennie urged the Scottish Government to “call in the cavalry” on contact tracing.
“The current test and protect system is failing us and potentially putting thousands at risk,” he said.
"With Scotland facing its highest level of infections yet, now is the time to call in the contact tracing cavalry and ensure that there are enough staff to reverse this week's collapse in contact tracing performance.
"This is the test of whether the Scottish Government has the extra staff that it promised would be available if necessary.”
The recent spike in cases has been linked to the Euro 2020 championships.
Figures from Public Health Scotland published on Wednesday showed there were almost 2,000 people who attended a Euros-related event while infectious with the virus.
Professor Leitch said on Thursday that the true figure is likely to be higher.
He said: “To keep it in perspective, there were 32,000 positives since the Euros began.
“And 2,000 of those positives, in their Test and Protect interviews, say they were at something to do with the Euros.
“So that will be an underestimate, some won’t have told us that, some won’t have appreciated that was important.”