More than 120 people tested positive for Covid-19 as the north-east recorded its highest-ever number of cases in a single day.
A total of 122 cases were reported in NHS Grampian on Wednesday – up from 49 the previous day.
There were 66 cases in Aberdeen, with a further 54 in Aberdeenshire and two in Moray.
Public health chiefs are attributing the significant rise in cases to an outbreak at the Kepak McIntosh Donald food processing plant in Portlethen.
Since a cluster of cases was identified there last week, testing has been offered to all employees, regardless of whether or not they have symptoms.
The move has since found 78 positive cases at the site – where an incident management team (IMT) has been set up in a bid to control and investigate the outbreak.
A spokeswoman for NHS Grampian said: “We are investigating 78 detected cases of Covid-19 associated with the Kepak McIntosh Donald plant in Portlethen. An Incident Management Team, with representation from the NHS, the plant, environmental health and Food Standards Scotland, has been set up.
“Following a small number of confirmed cases associated with the plant – and after discussions with management there – we offered asymptomatic testing to all employees on Monday. More than 200 staff took up the offer.
“These results are now being processed and account for much of the increase in our case numbers in Grampian. They are not the only reason behind today’s increase in case numbers – we continue to see other clusters of cases and the virus continues to circulate in the community.
“We are working closely with Kepak McIntosh Donald and a number of other partners to ensure all the correct control measures are in place. There is no evidence at this time to suggest this cluster has spread beyond those working at the plant.
“Given the large number of people who were tested it is likely further cases could be confirmed in the coming days.
“As noted above, Covid-19 is circulating in the community. Everyone should remember the FACTS guidance and play their part in limiting its spread as much as possible.”
News of the outbreak had led to concerns the north-east could be placed under tightened coronavirus restrictions – but it was downplayed by expert Hugh Pennington.
The emeritus professor of bacteriology at Aberdeen University believes there is no need for concern as the new cases are largely isolated in one cluster.
He said: “You can get big outbreaks like this from time to time which skew the figures for a particular area very dramatically. They are fairly straightforward to contain as long as you have an adequate testing procedure in place.
“When you know there’s an outbreak, you can do something about it. If there were cases scattered around rural areas with no real indication of where they came from, that would be a cause for concern.
“Large confined outbreaks are better from a community point of view because they can be controlled much more easily.
“With this kind of thing, there is no need to worry.”
A total of 44 deaths, including one in Aberdeen, were recorded bringing the total number of Covid-19 related deaths in Scotland to 3,588.
The latest figures take the number of positive cases in Scotland since the outbreak began to 90,961 with the new cases representing 6.8% of newly-tested individuals.
A total of 1,161 people are in hospital with recently confirmed Covid-19 and 84 of those are receiving treatment in intensive care.
Meanwhile, the deaths of 288 people in the north-east have now been linked to coronavirus, according to the latest figures.
The figures released by National Records of Scotland (NRS) show 141 deaths have been recorded in Aberdeen, 125 in Aberdeenshire and 22 in Moray since the beginning of the pandemic.
Last week, six new deaths were recorded in the NHS Grampian area.
The NRS figures are different from those published daily by the Scottish Government as it includes all deaths where Covid-19, including suspected cases, is mentioned on a person’s death certificate.