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Coronavirus (COVID-19): state of the epidemic - 1 October 2021

This report brings together the different sources of evidence and data about the Covid epidemic to summarise the current situation, why we are at that place, and what is likely to happen next.

Coronavirus (COVID-19): state of the epidemic - 1 October 2021
State of the Epidemic in Scotland – 1st October 2021

State of the Epidemic in Scotland – 1st October 2021

Background

This report summarises the current situation on the Covid-19 epidemic in Scotland. It brings together the different sources of evidence and data about the epidemic in Scotland at this point in time, why we are at that place, and what is likely to happen next. This summarises the data up to and including 30 September 2021 on Covid-19 in Scotland. This updates the previous publication published on 24 September 2021[1]. The information in this document helps the Scottish Government, the health service and the wider public sector respond to the epidemic and put in place what is needed to keep us safe and treat people who have the virus.

This edition of the State of the Epidemic summarises current data on Covid-19 at a national and local level, and how Scotland currently compares to the rest of the UK. It looks at the vaccination program in Scotland and its impact. Information is provided about variants of concern and what impact these may have. Bringing this information together in one place gives the opportunity to better understand the current state of the epidemic in Scotland.

Key Points

  • The reproduction rate R in Scotland, as of 14 September, is estimated as being between 0.7 and 1.0. This is a decrease in the lower and upper limits from last week.
  • An average of 2,833 cases were reported per day in the 7 days to 30 September, which is a 31% decrease in reported cases since 23 September.
  • There were 372 weekly cases per 100,000 in the week to 27 September (by specimen date), which is a decrease since last week. This is now lower than the most recent peak (825 weekly cases per 100,000 on 6 September) and lower than the peak in July (425 weekly cases per 100,000 recorded on 3 July).
  • Case rates have decreased across all age bands in the week to 27 September. As of 27 September, the highest case rates were observed amongst under 20s, followed by 40-59, 20-39, 60-79 and 80+.
  • As determined through the latest weekly ONS survey, the estimated proportion of people becoming infected with SARS-CoV-2 in the community in Scotland decreased in the last week (week ending 25 September 2021).
  • Latest modelled estimates suggest that as of 14 September there were between 162 and 213 new daily infections per 100,000 people in Scotland. This is a decrease in the lower and upper limits since last week.
  • There were 165 deaths registered in Scotland where coronavirus was mentioned on the death certificate in the week ending 26 September.
  • Average hospital admissions (3-week rolling average) related to Covid-19 in children have increased amongst 2-17 year olds over the last week but have decreased amongst 0-1 and 18-21 year olds in the same period.
  • South Ayrshire currently has the highest weekly case rate in Scotland reporting 578 weekly cases per 100,000 in the week to 27 September, followed by East Ayrshire with 549 weekly cases per 100,000, West Lothian with 522 weekly cases per 100,000, and West Dunbartonshire with 518 weekly cases per 100,000 population. All local authorities reported over 100 weekly cases per 100,000 population in the last week, except for Shetland and Orkney. Shetland reported the lowest case rate with 52 weekly cases per 100,000 in the same period.
  • Nationwide, levels of Covid-19 in wastewater have continued their decline, decreasing by 18% since last week. This puts wastewater viral levels somewhat below the July peak, as is the case for the rate of new cases.
  • Hospital and ICU occupancies have plateaued and are likely to fall in the coming weeks.
  • Over 4.1 million people in Scotland have been given a first vaccine against SARS-CoV-2, and over 3.8 million have received a second dose by 30 September.
  • The Delta variant remains the dominant strain in Scotland.

Method

This report brings together a wide range of publically available figures from a range of data sources. These include publications by Scottish Government, Public Heath Scotland, National Records of Scotland and Office for National Statistics along with scientific publications and SAGE summaries where appropriate to summarise the state of the epidemic in Scotland in a given week. We also provide information on public attitudes to the virus from weekly YouGov polling surveys.

The national picture

The latest R value for Scotland, as of 14 September (published on 30 September and using data to 27 September)[2], was between 0.7 and 1.0 (Figure 1), with a growth rate of between -4% and -1%. This is a decrease in the lower and upper limits from last week.

Figure 1: R in Scotland over time

This column chart shows the estimated range of R over time, from late September 2020. The R number has varied over the pandemic with the estimated range moving above 1 in Autumn 2020, January 2021, June 2021 and again at the end of August 2021. 

The latest R value for Scotland is estimated to be between 0.7 to 1.0, a further decrease in the lower and upper limits for the fourth consecutive week.

An average of 2,833 cases were reported per day in the 7 days to 30 September. This is a 31% decrease from the daily average cases recorded a week earlier to 23 September[3]. In the week 18-24 September 2021, there were 633 cases (PCR testing only) per 100,000 amongst the unvaccinated individuals, compared to 280 cases per 100,000 for those that had been vaccinated with two doses[4]. Our current position is 372 weekly cases per 100,000 in the week to 27 September (by specimen date)[5]. This is lower than the most recent peak of 825 weekly cases per 100,000 on 6 September and lower than the previous peak of 425 weekly cases recorded on 3 July (see Figure 2).

The number of locations where the levels of SARS-CoV-2 in wastewater are monitored has increased to 110 sites around Scotland. In contrast to Covid-19 case records, virus shedding into wastewater is a biological process. This means that wastewater data is unaffected by factors that impact whether testing is done. Nationwide, levels of Covid-19 in wastewater have continued their decline, decreasing by 18% since last week. This puts wastewater viral levels somewhat below the July peak, as is the case for the rate of new cases.

Figure 2: Seven day case rate for Scotland by specimen date. Refers to PCR testing only.

This line graph shows weekly cases per 100,000 people over time, from mid-September 2020. The case rate rose from a low of 25 in September to 170 in October 2020. It then reduced to just over 100 by the beginning of December 2020. At the end of December it rose sharply to just over 300 at the start of January 2021 which then continued to decrease until mid-May.  

There has been a sharp increase in case rates from mid-May to beginning of July 2021 followed by a sharp decline. Case rates started to increase again at the beginning of August 2021 and surpassed the peak seen at the start of July 2021. Case rates reached the peak on 6 September and started to go down since then. It is now lower than the peak of July.

Case rates have decreased across all age bands in the week to 27 September. As of 27 September, the highest case rates were observed amongst under 20s, followed by 40-59, 20-39, 60-79 and 80+ (Figure 3).

Figure 3: Seven day case rate in Scotland by age group by specimen date [6]. Refers to PCR testing only.

This line graph shows weekly cases per 100,000 people for five different age bands over time, from mid-September 2020. Each age band shows a similar trend with a peak in cases in January, with the 20 to 39 age band having the highest case rate, and the under 20 age band having the lowest case rate. Case rates reduced in all age groups from this peak and then started to increase again sharply from mid-May, reaching a peak at the beginning of July 2021. 7 day case rates per 100,000 population then started to decrease sharply followed by a sharp increase in cases in mid-August 2021. Case rates started to go down at the start of September for all age groups and have continued to do so.

Not everyone who has the virus will be tested, as many people do not realise they have Covid-19, or they have mild symptoms and do not come forward. Latest modelled estimates suggest that, as at 14 September, the incidence of new daily infections in Scotland was between 162 and 213 new infections per 100,000[7]. This equates to between 8,900 and 11,600 people becoming infected each day in Scotland. This is a decrease in the lower and upper limits since last week.

The number of people in hospital with confirmed Covid-19 for less than 28 days peaked at 2,053 on 22 January and decreased to a low of 58 on 6 May[8]. This has since increased and as of 30 September there were 998 patients in hospital with Covid-19. This compares to 1,057 people in hospital on 23 September (Figure 4). The latest data from PHS shows 705 admissions to hospital for people with confirmed Covid-19 in the week to 26 September compared to 975 in the week to 19 September[9]. In the 4 weeks to 24 September 34.3% of acute Covid-19 hospital admissions were in unvaccinated individuals[10]. For context, as of 29 September, 91.9% of adults aged 18+ (91.4% of adults aged 16+) have had at least one dose of the vaccine and vaccinated figures include the elderly and vulnerable groups. Overall, individuals in the oldest age groups were most likely to be hospitalised. In all age groups, the rate of admissions per 100,000 was higher in unvaccinated individuals compared to fully vaccinated individuals in the week to 24 September. Unvaccinated individuals were 3 to 4 times more likely to be in hospital with Covid-19 compared to fully vaccinated (depending on age)[11].

As the population is increasingly vaccinated more of the patients in hospital will be fully or partially vaccinated. Therefore, it is important that we can differentiate between patients in hospital because of COVID-19 rather than with COVID-19. PHS estimates that as at June 2021 72% of acute hospital admissions have a primary diagnosis of COVID-19. The trend has been decreasing since January 2021, and has fluctuated between 66% and 78%[12].

Figure 4: Patients in hospital (including those in ICU) (with length of stay 28 days or less) and ICU [13] with recently confirmed Covid-19

This line chart shows the daily number of patients in hospital and ICU (or combined ICU/ HDU) across Scotland with recently confirmed Covid-19 with a length of stay of 28 days or less since 11 September 2020. Covid-19 patients in hospital (including those in ICU) increased sharply from the end-September 2020 reaching a peak at the beginning of November. Patients in hospital then stabilised before a decrease at the beginning of December. It then started rising sharply from the end of December, reaching a peak of over 2,000 on 22 January. The number of patients in hospital decreased sharply since then before plateauing throughout May and June. It then rose to over 500 patients in hospital in July and decreased by the end of August. It then rose again reaching over a 1,000 patients in hospital by mid-September. A slight decrease in patients in hospital has occurred over the last week. 

A line for patients in ICU follows a similar pattern with an increase seen from end-September 2020. It then reached a peak of over 100 patients in ICU with length of stay 28 days or less at the beginning of November and then decreased to just below 50 patients in ICU in December 2020. Then a sharper increase is seen in patients in ICU by the end of January before it started to decrease. The number of patients in ICU remained low throughout late spring and early summer before a slight increase in July. It then decreased a little before further increase by mid-September. The number of patients in ICU has been decreasing over the last week.

There were 165 deaths registered where Covid-19 was mentioned on the death certificate in the week to 26 September. This is an increase of 30 (+22%) in the number of deaths from the previous week, and 75% lower than the peak in April 2020 (663 deaths). The proportion of deaths in care homes decreased from 60% in April 2020 to 13% in the week to 26 September, with 21 deaths occurring in care homes[14]. In the week ending 24 September, deaths involving coronavirus have increased in those aged 15-44 (from 2 to 3 deaths), 45-64 (from 15 to 25 deaths), 65-74 (from 12 to 28 deaths), 75-84 (from 12 to 50 deaths) and among those aged 85+ (from 17 to 59) compared to week ending 5 September. Deaths remained at 0 in those aged under 15 in the same period[15](Figure 5). From 29 December 2020 to 17 September 2021, 81.1% of Covid-19 deaths were in unvaccinated individuals[16]. Amongst those individuals who have been vaccinated with two doses of Covid-19 vaccine, 79.5% of the confirmed Covid-19 deaths occurred in the 70+ age group[17].

Figure 5: Deaths by age group (weekly total by week beginning, NRS) 12

This line graph shows the weekly number of deaths for seven different age groups over time, from March 2020. In April 2020 the number of deaths in the four age groups over 45 reached a peak, with the highest number of deaths being in the over 85 age group. Deaths then declined steeply and the number of deaths was very low in all age groups from July to September 2020. In October the number of deaths started to increase and then plateaued during November and December 2020 for the four age groups over 45. At the end of December deaths rose steeply again to another peak in January 2021, with the highest deaths being in the over 85 age group. The number of deaths has since declined steeply with the largest decrease in the over 85 age group, followed by a sharp decline in the 75 to 84 age group. Since mid-June 2021 there has been a slight increase in deaths overall, with the greatest increase in the 45 plus age groups. However, the number of deaths in all age groups remained low with only a slight recent increase seen with 165 deaths registered over the latest week. Deaths in the under 44 age groups have remained very low throughout the whole period.

How Scotland compares with the rest of the UK

The ONS Covid-19 Infection Survey estimates that in the week 19 to 25 September 2021, the estimated percentage of the community population (private households) testing positive for Covid-19 in Scotland was 1.85% (95% credible interval: 1.56% to 2.17%). The percentage of people testing positive for Covid-19 in the community population decreased in the most recent week. Estimates for the same week in the other UK nations are as follows: 1.21% (95% credible interval: 1.13% to 1.28%) for England, 1.76% (95% credible interval: 1.41% to 2.15%) for Wales and 1.53% (95% credible interval: 1.11% to 2.03%) for Northern Ireland. This equates to around 1 in 55 people in Scotland, 1 in 85 in England, 1 in 65 in Northern Ireland and 1 in 55 in Wales[18].

The ONS Covid-19 Infection Survey estimated that in the week beginning 23 August 2021, 93.3% (95% CI: 91.9% to 94.4%) of the adult community population in Scotland would have tested positive for antibodies against SARS-CoV-2, as a result of having the infection in the past or being vaccinated. This compares to 93.6% in England (95% CI: 92.5% to 94.5%), 91.2% in Wales (95% CI: 89.5% to 92.7%) and 91.9% in Northern Ireland (95% CI: 88.4% to 94.0%)[19].

An estimated 1.5% of the community population in the UK were experiencing self-reported long Covid symptoms (symptoms persisting for more than four weeks after the first suspected coronavirus (Covid-19) infection that were not explained by something else) in the 4 weeks ending 1 August 2021. In Scotland, 74,000 people (1.41% of the respective population) living in private households self-reported long Covid symptoms for this period. This compares to 1.43% in Wales, 1.53% in England and 1.03% in Northern Ireland[20].

Average daily deaths in Scotland (4 per 1 million population) in the week to 30 September are above England, Wales and Northern Ireland (2 per 1 million each)[21]. Average daily cases in Scotland (518 per 1 million) in the week to 30 September are below Wales (897 per 1 million) and Northern Ireland (575 per 1 million) but above England (502 per 1 million)[22].

Situation by local authority within Scotland

South Ayrshire currently has the highest weekly case rate in Scotland reporting 578 weekly cases per 100,000 in the week to 27 September, followed by East Ayrshire with 549 weekly cases per 100,000, West Lothian with 522 weekly cases per 100,000, West Dunbartonshire with 518 weekly cases per 100,000, North Lanarkshire with 472 weekly cases per 100,000, and Dundee City with 472 weekly cases per 100,000 population. All local authorities reported over 100 weekly cases per 100,000 population in the last week, except for Shetland and Orkney (Table 1). Case rates have decreased across most local authorities over the last week however there are still very high levels of case rates across Scotland (Figure 6). Shetland has the lowest case rate in Scotland, reporting 52 weekly cases per 100,000 in the week to 27 September[23].

Table 1: Total new weekly cases per 100,000 population to 27 September 2021, in order of prevalence
Local authority Total new cases in the week, per 100,000 population Change since previous week
South Ayrshire 578 -20
East Ayrshire 549 -32
West Lothian 522 +20
West Dunbartonshire 518 -226
North Lanarkshire 472 -148
Dundee City 472 -42
North Ayrshire 463 -100
Fife 450 -68
Falkirk 450 -78
Clackmannanshire 417 -58
Renfrewshire 400 -177
Midlothian 392 -99
East Dunbartonshire 392 -203
Inverclyde 389 -127
Stirling 389 -104
South Lanarkshire 387 -122
Perth and Kinross 366 -16
Aberdeenshire 360 -79
East Renfrewshire 358 -130
Glasgow City 355 -129
Dumfries and Galloway 355 +7
Argyll and Bute 306 -104
Aberdeen City 296 -85
City of Edinburgh 273 -60
East Lothian 263 -44
Angus 262 -43
Na h-Eileanan Siar 230 +64
Moray 217 +8
Scottish Borders 204 -80
Highland 175 -119
Orkney Islands 85 -22
Shetland Islands 52 -70
Scotland 372 -87
Figure 6: Map of weekly new positive cases per 100,000 people in Scotland

This colour coded map of Scotland shows the different rates of weekly positive cases per 100,000 people across Scotland’s Local Authorities. The colours range from grey for under 50 weekly cases per 100,000, through very light orange for 50 to 100, orange for 100-300, darker orange for 300-500, and very dark orange for over 500 weekly cases per 100,000 people. 

Four local authorities are showing as very dark orange on the map this week, with over 500 weekly cases. These are South Ayrshire, East Ayrshire, West Lothian and West Dunbartonshire. No local authorities are showing as grey for under 50 weekly cases per 100,000. Orkney and Shetland are shown as very light orange, with 50-100 weekly cases per 100,000 people. Aberdeen, Angus, Edinburgh, East Lothian, Highland, Moray, Na h-Eileanan Siar and Scottish Borders are showing as orange with 100-300 weekly cases. All other local authorities are shown as darker orange with 300-500 weekly cases per 100,000.

The most recent modelling predicts, based on data up to 27 September, that for the week commencing 10 October 2021, there are 29 local authorities which are expected to exceed 50 cases per 100,000 population with at least 75% probability. Of these, 8 local authorities (Dundee, East Ayrshire, Fife, Glasgow, North Lanarkshire, South Ayrshire, South Lanarkshire and West Lothian) are expected to exceed 300 cases per 100,000 with at least 75% probability. There are no local authorities which are expected to exceed 500 cases per 100,000 population with at least 75% probability[24].

Children and Education

Schools have resumed in Scotland and the majority of children and young people had returned to full time education by the week ending 20 August. University students in Scotland continue to return.

Over the last week there was a decrease in the total number of Covid-19 cases in young people aged under 22, which has decreased from 10,973 cases in the week to 19 September to 8,475 cases in the week ending 26 September. 7 day cases per 100,000 have also decreased in all age groups in the week ending 26 September (Figure 7). The percentage of cases made up of children under 12 was just under 48% (4,039 cases) compared to just under 42% (4,594 cases) in the previous week[25].The percentage of cases made up of 18-21 year olds remained at 9% in the week to 26 September compared to the week ending 19 September. Following the return of some universities, there is no evidence of an uptick in cases in the 18-21 year age group.

The rate of testing decreased amongst all age groups in the week ending 26 September. Test positivity rates have decreased in all age groups, except for 5-11 year olds in the same period. The proportion of positive cases who report having been in an education setting in the 7 day period prior to the onset of symptoms has increased slightly to 20.8% in week ending 26 September, from 20.3% of positive cases in the previous week. Hospital admissions (3 week rolling average) in children and young adults increased slightly amongst 2-4 year olds (from 9.3 to 9.7), 5-11 year olds (from 17.7 to 18.3) and 12-17 year olds (from 19.7 to 24.0), however decreased amongst 0-1 year olds (from 30.3 to 29.3), 18-19 year olds (from 8.7 to 8.0) and amongst 20-21 year olds (from 9.3 to 5.3) in the period 2 – 22 September compared to the previous three-week period (26 August – 15 September).

Vaccine uptake in 17-21 year olds as at 27 September was 77.2% for the first dose and 54.3% for the second dose[26]. Please note that under half of Scottish students are in this age category and only Scottish students (i.e. registered with a GP in Scotland) are included in the figures. Covid-19 infection survey estimated that up to the week beginning 23 August 2021, the percentage of 16-24 year olds testing positive for antibodies increased to 88.7%[27].

Figure 7: Seven day case rate in Scotland by age group by specimen date for children and young people (week ending 26 September). Refers to PCR testing only.

This figure shows the 7-day case rate of school pupils and younger adults of under 22 years of age who tested positive for Covid-19, grouped in seven age groups, during the period 14 February 2021 to 26 September 2021. Markers also show all Scotland case rate for comparison.

The rates for all age groups have varied over time. Case rates remained relatively low from mid-February to May. They then started to increase in May and peaked in early July, with the highest case rate among 18-19 year olds. The rates decreased across all age groups in late July. Case rates then started to rise at the beginning of August 2021, reaching the peak early September. These then started to go down. In the latest week ending 26 September, the 7 day case rates declined in all age groups.

Looking ahead

Changes in patterns of mixing and adherence to restrictions will impact on future case numbers. The Scottish Contact Survey measures times and settings that people mix where they could potentially spread Covid-19. Average contacts have increased by approximately 17% in the last two weeks (comparing surveys pertaining to 9th September - 15th September and 23rd September - 29th September) with a current level of 5.4 daily contacts.

Contacts within the work have increased by around 75% whereas contacts in the other setting (contacts outside home, school and work) have decreased by 9% in the last two weeks. Contacts within the home have remained at a similar level over the same period.

All age groups between 18-59 have reported an increase in overall contacts with those aged 18-29 almost doubling in the last two weeks.

The proportion of individuals visiting a pub or restaurant increased from approximately 43% to 45% with individuals visiting a non-essential shop increasing from 39% to 41% in the last two weeks.

Self-reported compliance with the current regulations and guidance has decreased since January but remains at a high level. On 21-22 September, 68% of people reported 'complete' or 'almost complete' compliance[28].

Hospital and Intensive care unit occupancies have plateaued and are likely to fall in the coming weeks (Figure 8)[29].

Figure 8: Medium term projections of modelled hospital bed demand, from Scottish Government modelling [30]

This line graph shows projected demand for hospital beds over time from mid-September to mid-October 2021, and includes two scenarios; ‘better’ and ‘central’. Markers also show the actual number of hospital beds that were required until end-September. Based on the recent changes in cases, hospital beds are projected to decrease in both ’central’ and ‘better’ scenarios.

Vaccinations are continuing across the priority groups and 91.4% of the 16+ population in Scotland has now been vaccinated with the first dose[31]. The first vaccines were administered on Tuesday 8 December and 4,189,701 people had received their first dose by 30 September 2021[32]. By age group, almost 100% of individuals aged 55+, 96% of those aged 50-54, 92% of those aged 40-49, 83% of those aged 30-39, 77% of those aged 18-29, 71% of those aged 16-17 and 14% of those aged 12-15 have received their first vaccination (Figure 9).

Almost 100% of individuals aged 60+, 97% of those aged 55-59, 93% of those aged 50-54, 86% of those aged 40-49, 75% of those aged 30-39, 63% of those aged 18-29, 10% of those aged 16-17 and 0% of those aged 12-15 have received their second dose. Overall, 3,837,689 people (84.4% of those aged 16 and over) had received their second dose by 30 September[33]. There remains a low level of deaths amongst the vaccinated individuals (Figure 5).

Figure 9: Estimated percentage of adults vaccinated by 30 September 2021

This bar chart shows the percentage of people that have received their first and second dose of the Covid vaccine so far, for twelve age groups. The six groups aged over 55 have more than 99% of people vaccinated with the first dose and more than 97% of people vaccinated with the second dose. Of those aged 50-54, 96% have received their first dose and 93% have received their second dose. Younger age groups have lower percentages vaccinated, with 92% of 40-49 year olds having received their first dose and 86% the second dose, 83% of the 30-39 year olds having received their first and 75% having received their second dose, 77% of 18 to 29 year olds having received the first dose and 63% having received the second dose, 71% of the 16-17 year olds having received their first dose and 10% their second dose, and 14% of 12-15 year olds having received their first dose and 0% having received their second dose of the vaccine.

The proportion of people surveyed who said they have been vaccinated for Covid-19 is high. 91% of all respondents have already received at least their first vaccine dose. Of those not vaccinated (and small base must be noted), 13% report they are likely to be vaccinated when a vaccine becomes available to them[34].

How the virus is changing

The variant of concern Delta, also referred to as VOC-21APR-02 (first identified in India) is more transmissible than Alpha variant [35] [36] [37]. It quickly replaced Alpha (VOC-20DEC-01), first identified in the UK, as the dominant strain in Scotland, and 80,387 cases have now been identified as Delta to 29 September 2021.

To date there are five 'variants of concern' (VOCs) and eleven 'variants under investigation' (VUIs)[38]. There is a concern that some of these new variants may partially escape immunity, from both natural infection and from vaccines currently being deployed and we are monitoring the evidence on this[39] [40] [41]. Up to 29 September there have been 62 genomically confirmed cases of the variant Beta/VOC-20DEC-02 (first detected in South Africa), and 23 cases of Gamma in Scotland. Genomically confirmed cases of other VOCs and VUIs remain low, there have been no new cases of other VOCs or VUIs in the last week (Figure 10). There remains uncertainty regarding the impact of the Delta variant on severity of illness, treatment or reinfections. As more data is analysed we shall become more certain of the impact of Delta on infections, hospitalisations and disease severity and long term vaccine protection effects.

Figure 10: Variants detected in Scotland by sequencing (data up to 29 September and reported weekly [42]

This line graph shows the number of cases of the variants of concern and variants of interest that have been detected by sequencing in Scotland each week, from 25 January to 29 September 2021.

Beta, also known as VOC-20DEC-02, first detected in South Africa, was increasing steadily since late January from 3 cases to 60 cases on the 7 July, and then increased to 62 cases by 11 August. Beta has remained at 62 cases since then. Eta, or VUI-21FEB-03, first identified in Nigeria, rapidly increased since mid-March and reached 40 cases at the end of May. Eta has remained stable over the last 18 weeks. Gamma increased to 23 cases in the week to 25 August but has not yet increased any further. There are also 27 cases of Kappa, or VUI-21APR-01, first identified in India, no change since mid-May. The first case of VUI-21Jul-01 emerged in the week to 4 August with three new case identified in the week to 1 September, however no change over the last 4 weeks. Delta, also known as VOC-21APR-02, first identified in India, has seen a rapid increase in the past 20 weeks to 80,387 cases, an increase of 6,891 cases since the week before.

How well vaccines work

A large study from the University of Oxford and Office of National Statistics shows that with Delta, Pfizer-BioNTech and Oxford-AstraZeneca vaccines still offer good protection against new infections, but effectiveness is reduced compared with Alpha[43]. Public Health England analysis shows that vaccines are highly effective against hospitalisation from Delta variant with similar vaccine effectiveness against hospitalisation seen with the Alpha and Delta variants at 93% and 96% respectively after two doses of vaccine. There was a 14% absolute reduction in vaccine effectiveness against symptomatic disease after a single vaccine dose with Delta compared to Alpha, and a smaller 10% reduction in effectiveness after 2 doses. Vaccine effectiveness against symptomatic disease is high for both Alpha (89%) and Delta after two doses (79%)[44]. EAVE II data from Scotland also shows that both the Oxford–AstraZeneca and Pfizer–BioNTech Covid-19 vaccines are effective in reducing the risk of SARS-CoV-2 infection and Covid-19 hospitalisation in people with the Delta variant, but effectiveness against infection appeared to be diminished when compared to those with Alpha[45]. The vaccine effectiveness expert committee recently published their consensus view on the effectiveness of different vaccines on infections, symptomatic disease, and severe disease [46].

Next steps

The Scottish Government continues to work closely with Public Health Scotland and modelling groups to monitor what happens following the high number of cases in Scotland this week and how this effects the course of the epidemic.

Each week this report will provide an overview of the current Covid-19 situation in Scotland. This will include real time data on case rates, hospitalisations and deaths and how Scotland's figures compare to those from the rest of the UK.

Modelling can tell us where the epidemic is likely to be heading. Local data and data by age group can highlight where problems arise, which can help in addressing some of these issues. In the coming weeks the roll out of the vaccine will continue to be monitored along with the impact of this on case rates and deaths among different age cohorts. Investigations are ongoing by NERVTAG, SPI-M, SAGE, Public Health England and Public Health Scotland regarding the impact of new variants and of vaccination; this will be reflected here as work is undertaken.


Contact

Email: modellingcoronavirus@gov.scot