Coronavirus in Scotland: Virus transmission rate 'could be increasing'
Scotland's coronavirus infection rate could be increasing after a number of small clusters were detected.
A cluster in Glasgow has been linked to secondary school pupils.
First Minister Nicola Sturgeon said the reproduction rate of the virus - the R number - could now be above one.
Scientists believe an R number higher than one is dangerous as it means the number of cases can in theory spread exponentially.
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This is because each person with the virus would on average be infecting more than one other person.
Ms Sturgeon said that the upper estimate of the R number in Scotland "could have been as high as 1.3" last week. The figure was previously estimated to be between 0.6 and one.
But the first minister stressed that there were only thought to be have been about 250 infectious people in Scotland last week.
She said this meant there was "not the same level of concern as you would have had back in May when prevalence was much higher".
She added: "When the prevalence across the country is low the R number will be disproportionately affected by outbreaks on the scale of the one in Aberdeen.
"While we shouldn't be unduly alarmed, it is equally important that we're not in any way complacent.
"Covid is still present and it will spread really rapidly if given an opportunity".
Ms Sturgeon said the data suggested there was a particular problem with house parties, and urged people to comply with the rules on visiting other people's homes.
A total of 47 new cases have been confirmed across the country since Wednesday.
Ms Sturgeon said 26 of the new cases were in the Grampian health board area - although it was not clear how many are linked to the ongoing outbreak in Aberdeen which has so far seen 182 people test positive.
Meanwhile, officials say the five people who tested positive in Orkney worked together on a fishing boat, before travelling to homes across the islands.
Possible links between the Orkney cluster and the outbreak in Aberdeen are being investigated.
A "household cluster" is being investigated in Peterhead after a member of staff at Peterhead Central primary tested positive.
Later it was confirmed that a second employee had also been infected.
And a cluster in the Baillieston area of Glasgow now has 11 positive cases, including a number of pupils at Bannerman High School.
However, officials have stressed that none of the pupils has attended the school since it reopened on Wednesday, and all are self-isolating.
The first minister said that these kind of clusters were "inevitable", and insisted that the test and protect system of contact tracing was working as intended.
Later it emerged that a pupil at St Ambrose High School in Coatbridge is also isolating with their family after testing positive for Covid-19, according to NHS Lanarkshire.
The student had been displaying mild symptoms since Tuesday but had not attended school at all.