Coronavirus (COVID-19): modelling the epidemic in Scotland

22nd October 2021

Background
This is a report on the Scottish Government modelling of the spread and level of Covid-19. This updates the previous publication on modelling of Covid-19 in Scotland published on 14th October 2021.

The estimates in this document help the Scottish Government, the health service and the wider public sector plan and put into place what is needed to keep us safe and treat people who have the virus.
This edition of the research findings focuses on the epidemic as a whole, looking at estimates of R, growth rate and incidence as well as local measures of change in the epidemic.

In Scotland, the modelled estimate for R is between 0.8 and 1.0, with the growth rate between -3% and 0%.

Key Points
• The reproduction rate R in Scotland is currently estimated as being
between 0.8 and 1.0, as of 5 th October. This is unchanged from last week.
• The number of new daily infections for Scotland is estimated as being between 77 and 114, per 100,000 people. The lower and upper limits have decreased since last week.
• The growth rate for Scotland is currently estimated as between -3% and 0%. This is unchanged from last week.
• Average contacts have decreased by approximately 14% in the last two weeks (comparing surveys pertaining to 23rd September - 29th September and 7th October - 13th October) with a current level of 4.7 daily contacts.

Coronavirus (COVID-19): Analysis

• Mean contacts within the work setting have decreased by around 48% whereas contacts in the other setting (contacts outside home, school and work) have increased by 11% in the last two weeks. Contacts within the home have remained at a similar level over the same period.
• Those aged between 30-39 have reported the biggest decrease in
interactions with those aged under 18 in the last two weeks whereas
interactions between the 18-29 age group with those under 18 has
shown the biggest increase.
• The proportion of individuals visiting another's home decreased from approximately 51% to 44% whilst individuals visiting a pub or
restaurant rose from 45% to 47% in the last two weeks.
• The proportion of contacts reported to have been indoors only has
remained at similar level to two weeks prior, currently at 66%.
• The number of people wearing a face covering where they have at
least one contact outside of the home has fallen from 87% to 80% in
the last two weeks.
• Hospital and ICU occupancies are in a gradual fall or a plateau. There continues to be uncertainty over hospital occupancy and intensive care in the next three weeks.
• Modelled rates of positive tests per 100K using data to 18th October indicate that, for the week commencing 31st October 2021, there are 28 local authorities which are expected to exceed 50 cases per 100K with at least 75% probability. There are 23 local authorities which are expected to exceed 100 cases per 100K with at least 75% probability.
• There are no local authorities which are expected to exceed 300
cases per 100K with at least 75% probability.
• Nationwide, after the decrease observed last week (5th to 11th October 2021), levels of Covid in wastewater have remained consistent.
• Modelling of long Covid estimates that on 7th November 2021 between 1.2% and 2.6% of the population are projected to self-classify with long Covid for 12 weeks or more after their first suspected Covid infection in Scotland. The upper and lower limits of the estimate are higher than last week.

Read the full report