Public Health Scotland’s weekly statistical report shows there were 21,914 reported cases of Covid-19 in the week up to July 3, a 42.5% increase from the 15,382 reported in the week before.
There was also an average of 1,450 patients in hospital with Covid-19 during the same week.
The figure is a stark increase from the 1,148 recorded the previous week, a jump of 26.3%.
Up to July 3, the report also found, there were 877 new admissions of patients with Covid-19, which had dropped from 1,062.
Up to three new strains of the virus have now been identified but no breakdown has been given of which variety may be responsible for the spike in cases.
In a letter to Health Secretary Humza Yousaf, Scottish Lib Dem leader Alex Cole-Hamilton asked for clarity on the future of testing for health and social care staff and on vaccination boosters expected for vulnerable groups in the coming months.
He said: “With Covid cases spiking once more, it seems bizarre for the Health Secretary to be talking about dismantling our defences.
“It seems as if he has learned nothing from the past two years.
“NHS staff and patients will be filled with dread at the prospect of an end to testing.
“What’s more, the Health Secretary’s recent comments seem to contradict the Scottish Government’s testing transition plan published in March which said routine asymptomatic testing of the health and social care workforce would play an ongoing role.”