Nearly 4,000 pupils were told to self-isolate in Lanarkshire last month according to new figures.
Council bosses in North and South Lanarkshire confirmed nearly 600 primary and secondary school youngsters tested positive for the virus in October.
In North Lanarkshire, a reported 2000 pupils had to self-isolate and 200 were confirmed as having the infection.
The news comes as the Scottish Government announced the recruitment of more than 1,400 teachers and support staff across the country.
Shotts MSP Alex Neil said: “In the middle of a global pandemic, it’s absolutely vital that local authorities are fully supported to ensure that our schools remain safe for pupils, teachers and staff.
“Thanks to significant investment from the SNP Government this summer, we now have hundreds of extra teachers and staff in our schools to support their safe re-opening.
“These additional teachers and support staff will not only bring much-needed resilience to Scotland’s education system, but they will help compensate for the loss of learning suffered by pupils during lockdown.
“I want to express my appreciation once again for our amazing teachers and wider schools workforce who are helping to ensure our young people continue to get the education they deserve during these tough times.”
Education Secretary John Swinney said schools are facing a “challenging situation”, but he insisted it is safe for youngsters to be in class.
He also said that while attendance levels are lower than last year, only a “very small proportion of positive cases” of Covid-19 have been linked to education.
A spokeswoman from North Lanarkshire Council said: “This is not unique to North Lanarkshire as schools across the country are experiencing cases of coronavirus which result in other pupils and staff being asked to self-isolate.
“We are doing all we can to keep our schools open and running as normally as possible, with a wide range of safety measures in place.”
