The rate of coronavirus infection in Scotland could increase after a number of small groups are detected.
Orkney health authorities are treating nine positive cases, while an Aberdeenshire primary school has been closed after a member of staff tested positive.
A cluster in Glasgow has been linked to secondary school students.
Prime Minister Nicola Sturgeon has said the virus’s reproduction rate – the R number – could now be more than one.
Scientists believe that an R number greater than one is dangerous because it means that the number of cases can in theory spread exponentially.
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In fact, each person infected with the virus would infect on average more than one other person.
Ms Sturgeon said the top estimate of the R-number in Scotland “could have reached 1.3” last week. The figure was previously estimated to be between 0.6 and one.
But the Prime Minister stressed that there were only 250 infectious people in Scotland last week.
She said that meant there was “not the same level of concern you would have had in May when the prevalence was much higher.”
She added, “When prevalence across the country is low, the R number will be disproportionately affected by outbreaks of the magnitude of Aberdeen.
“While we should not be unduly alarmed, it is equally important that we are not complacent in any way.
“Covid is still present and it will spread very quickly if the opportunity presents itself.”
Parties at home
Ms Sturgeon said the data suggested there was a particular problem with house parties and urged people to obey 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 is not known how many are linked to the ongoing outbreak in Aberdeen, which has so far seen 182 people tested positive.
Meanwhile, officials say the nine people who tested positive for Orkney Islands worked together, before heading to homes across the islands.
Possible links between the Orkney cluster and the Aberdeen epidemic are under study.
A “cluster of households” is being investigated in Peterhead after a staff member at Peterhead Central tested positive.
And a cluster of eight cases in Glasgow’s Baillieston area is believed to include a number of students from Bannerman High School.
However, officials stressed that none of the students have attended the school since it reopened on Wednesday, and that all are isolating themselves.
The prime minister said such clusters were “inevitable” and insisted that the contact tracing testing and protection system was working as intended.