Coronavirus (COVID-19): state of the epidemic - 17 September 2021

State of the Epidemic in Scotland – 17^th September 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 16 September 2021 on Covid-19 in Scotland. This updates the previous publication published on 10 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 the effects that are beginning to be seen from this. 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.

Please note, data on new cases and tests reported on 16 September are not included in this week's report due to technical issues affecting the availability of the data.

Key Points

• The reproduction rate R in Scotland, as of 31 August, is estimated as being between 1.0 and 1.3. This is a decrease in the lower and upper limits from last week.
• An average of 5,198 cases were reported per day in the 7 days to 15 September, which is an 18% decrease in reported cases since 8 September.
• There were 678 weekly cases per 100,000 in the week to 12 September (by specimen date), which is a decrease since last week. This is now lower than the most recent peak (824 weekly cases per 100,000 on 6 September) but higher than the peak in July (425 weekly cases per 100,000 recorded on 3 July).
• Case rates have gone down across all age bands, except for the 60-79 and 80+ year olds in the week to 12 September. As of 12 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 increased in the last week (week ending 11 September 2021), but the rate of increase has slowed.
• Latest modelled estimates suggest that as of 31 August there were between 169 and 278 new daily infections per 100,000 people in Scotland. This is an increase in the lower and upper limits since last week.
• There were 76 deaths registered in Scotland where coronavirus was mentioned on the death certificate in the week ending 12 September.
• Hospital admissions related to Covid-19 in children are the highest since the start of the pandemic.
• West Dunbartonshire currently has the highest weekly case rate in Scotland reporting 1,113 cases per 100,000 in the week to 12 September, followed by East Renfrewshire with 968 weekly cases per 100,000, and Inverclyde with 902 weekly cases per 100,000. All local authorities reported over 100 weekly cases per 100,000 population in the last week. Na h-Eileanan Siar reported the lowest case rate with 128 weekly cases per 100,000 in the same period.
• Nationwide, levels of Covid-19 in wastewater have risen by around 56% since the previous week.
• Hospital and ICU occupancies are rising. The scale of any future increase in hospital occupancy and intensive care use is highly uncertain, and depends on the number of infections.
• Over 4.1 million people in Scotland have been given a first vaccine against SARS-CoV-2, and almost 3.8 million have received a second dose by 16 September.
• The Delta variant of concern (VOC-21APR-02, first identified in India), 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 31 August (published on 16 September and using data to 6 September)^[2], was between 1.0 and 1.3 (Figure 1), with a growth rate of between 1% and 5%. This is a decrease in the lower and upper limits from last week.

An average of 5,198 cases were reported per day in the 7 days to 15 September. This is an 18% decrease from the daily average cases recorded a week earlier to 8 September^[3]. In the week 4-10 September 2021, there were 1,139 cases (PCR testing only) per 100,000 amongst the unvaccinated individuals, compared to 473 cases per 100,000 for those that had been vaccinated with two doses^[4]. Our current position is 678 weekly cases per 100,000 in the week to 12 September (by specimen date)^[5]. This is lower than the most recent peak of 824 weekly cases per 100,000 on 6 September but higher 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 risen by around 56% since the previous week. As a result Covid-19 levels in wastewater this week are at the highest reported since the start of the pandemic.

Case rates have decreased across all age bands over the last week, except for the 60-79 and 80+ year olds in the week to 12 September. As of 12 September, the highest case rates were observed amongst under 20s, followed by 40-59, 20-39, 60-79 and 80+. Case rates amongst 20-39 year olds decreased at a faster rate than 40-59 year olds and on 11 September case rates in the 20-39 year olds were lower (Figure 3).

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 31 August, the incidence of new daily infections in Scotland was between 169 and 278 new infections per 100,000^[7]. This equates to between 9,200 and 15,200 people becoming infected each day in Scotland. This is an increase 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 16 September there were 1,054 patients in hospital with Covid-19. This compares to 928 people in hospital on 9 September. Daily hospital admissions for people with Covid-19 have increased from a low of 6 on 5 May and were at 119 on 11 September^[9]. In the 4 weeks to 10 September 35.0% of acute Covid-19 hospital admissions were in unvaccinated individuals^[10].

There were 76 deaths registered where Covid-19 was mentioned on the death certificate in the week to 12 September. This is an increase of 18 (+31%) in the number of deaths from the previous week, and 89% lower than the peak in April 2020 (663 deaths). The proportion of deaths in care homes decreased from 60% in April 2020 to 8% in the week to 12 September, with 6 deaths occurring in care homes^[11]. In the week ending 12 September, deaths involving coronavirus have increased in those aged 65-74 (from 6 to 13 deaths), 75-84 (from 10 to 30 deaths) and among those aged 85+ (from 13 to 21) compared to week ending 22 August. Deaths remained at 0 in those aged under 15 in the same period¹¹ (Figure 4). From 29 December 2020 to 2 September 2021, 83.4% of Covid-19 deaths were in unvaccinated individuals^[12].

How Scotland compares with the rest of the UK

The ONS COVID-19 Infection Survey estimates that in the week 5 to 11 September 2021, the estimated percentage of the community population (private households) testing positive for COVID-19 in Scotland was 2.29% (95% credible interval: 1.94% to 2.67%). This is the highest level since the survey began in Autumn 2020, but the rate of increase appears to have slowed. Estimates for the same week in the other UK nations are as follows: 1.28% (95% credible interval: 1.19% to 1.36%) for England, 1.36% (95% credible interval: 0.97% to 1.83%) for Northern Ireland and 1.62% (95% credible interval: 1.27% to 2.01%) for Wales. This equates to around 1 in 45 people in Scotland, 1 in 80 in England, 1 in 75 in Northern Ireland and 1 in 60 in Wales^[13].

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%)^[14].

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^[15].

Average daily deaths in Scotland (2 per 1 million population) in the week to 15 September are in line with England (2 per 1 million), but below Northern Ireland (4 per 1 million) and Wales (3 per 1 million)^[16]. Average daily cases in Scotland (951 per 1 million) in the week to 15 September are above Northern Ireland (759 per 1 million), Wales (704 per 1 million) and England (405 per 1 million)¹⁶.

Situation by local authority within Scotland

West Dunbartonshire currently has the highest weekly case rate in Scotland reporting 1,113 weekly cases per 100,000 in the week to 12 September, followed by East Renfrewshire with 968 weekly cases per 100,000, Inverclyde with 902 weekly cases per 100,000, North Lanarkshire with 886 weekly cases per 100,000, Renfrewshire with 845 weekly cases per 100,000, and North Ayrshire with 804 weekly cases per 100,000 population. All local authorities reported over 100 weekly cases per 100,000 population in the last week (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 5). Na h-Eileanan Siar has the lowest case rate in Scotland, reporting 128 weekly cases per 100,000 in the week to 12 September^[17].

Table 1: Total new weekly cases per 100,000 population to 12 September 2021, in order of prevalence

Local authority	Total new cases in the week, per 100,000 population	Change since previous week
West Dunbartonshire	1,113	-101
East Renfrewshire	968	-120
Inverclyde	902	-337
North Lanarkshire	886	-373
Renfrewshire	845	-290
North Ayrshire	804	-31
Midlothian	777	-118
Dundee City	771	-66
Glasgow City	770	-274
South Lanarkshire	760	-236
East Dunbartonshire	759	-238
East Ayrshire	756	+29
West Lothian	755	-39
Fife	752	-29
Clackmannanshire	719	-253
Falkirk	670	-173
South Ayrshire	665	-62
Stirling	662	+6
Aberdeenshire	615	+69
City of Edinburgh	594	-154
Argyll and Bute	552	-280
Aberdeen City	522	-21
East Lothian	489	-154
Highland	480	-122
Dumfries and Galloway	468	-97
Angus	451	-111
Scottish Borders	440	-31
Perth and Kinross	398	+51
Shetland Islands	275	-9
Moray	250	+6
Orkney Islands	246	+156
Na h-Eileanan Siar	128	-53
Scotland	678	-136

The most recent modelling predicts, based on data up to 13 September, that for the week commencing 26 September 2021, there are 29 local authorities which are expected to exceed 50 cases per 100,000 population with at least 75% probability. Of these, 13 local authorities are expected to exceed 300 cases per 100,000 with at least 75% probability. These are East Ayrshire, East Dunbartonshire, East Renfrewshire, Fife, Glasgow City, Inverclyde, North Ayrshire, North Lanarkshire, Renfrewshire, South Ayrshire, South Lanarkshire, West Dunbartonshire and West Lothian. There are no local authorities which are expected to exceed 500 cases per 100,000 population with at least 75% probability (Figure 6)^[18].

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.

Over the last week there was a decrease in the total number of Covid-19 cases in young people aged under 20, which has gone down from 17,241 cases in the week to 5 September to 14,220 cases in the week ending 12 September. 7 day cases per 100,000 have also decreased in all age groups in the week ending 12 September (Figure 7). The percentage of cases made up of children under 12 was just under 47% (6,627 cases) compared to just under 44% (7,535 cases) in the previous week^[19].

The rate of testing decreased amongst all age groups in the week ending 12 September, except for 0-1 and 2-4 year olds. Test positivity rates have decreased in all age groups 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 17.8% in week ending 12 September, from 17.5% of positive cases in the previous week. Hospital admissions (3 week rolling average) in children increased across all age groups in the period 19 August to 8 September compared to the previous three-week period (12 August – 1 September). Hospital admissions related to Covid-19 in children are the highest since the start of the pandemic.

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 for most age groups, with the exception of the 18-29 year olds where there has been a 55% reduction in contacts. This has driven an overall reduction of approximately 10% in the last two weeks (comparing surveys pertaining to 26th August - 1st September and 9th September - 15th September) with a current level of 4.6 daily contacts.

Contacts within the work have decreased by 20% in the last two weeks whereas contacts within the home and other setting (contacts outside home, school and work) have remained at a similar level.

The proportion of individuals using public transport decreased from approximately 25% to 22% with individuals visiting a non-essential shop also decreasing, from 42% to 39%, 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 7-8 September, 65% of people reported 'complete' or 'almost complete' compliance^[20].

Hospital and ICU occupancies are rising. The scale of any future increase in hospital occupancy and intensive care use is highly uncertain, and depends on the number of infections (Figures 8 and 9)^[21].

Vaccinations are continuing across the priority groups and 91% of the 16+ population in Scotland has now been vaccinated with the first dose^[23]. The first vaccines were administered on Tuesday 8 December and 4,148,734 people had received their first dose by 16 September 2021^[24]. By age group, almost 100% of individuals aged 55+, 96% of those aged 50-54, 91% of those aged 40-49, 83% of those aged 30-39, 76% of those aged 18-29, and 66% of those aged 16-17 have received their first vaccination (Figure 10). Almost 100% of individuals aged 60+, 97% of those aged 55-59, 93% of those aged 50-54, 86% of those aged 40-49, 74% of those aged 30-39, 61% of those aged 18-29, and 9% of those aged 16-17 have received their second dose. Overall, 3,795,897 people (83% of those aged 16 and over) had received their second dose by 16 September^[25]. There remains a low level of deaths amongst the vaccinated individuals (Figure 4).

The proportion of people surveyed who said they have been vaccinated for Covid-19 is high. 90% of all respondents have already received at least their first vaccine dose. Of those not vaccinated (and small base must be noted), 5% report they are likely to be vaccinated when a vaccine becomes available to them^[26].

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 ^{[27] [28] [29]}. It quickly replaced Alpha (VOC-20DEC-01), first identified in the UK, as the dominant strain in Scotland, and 64,169 cases have now been identified as Delta to 15 September 2021.

To date there are five 'variants of concern' (VOCs) and eleven 'variants under investigation' (VUIs)^[30]. 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^{[31] [32] [33]}. Up to 15 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 11).

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^[35]. 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%)^[36]. 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^[37]. The vaccine effectiveness expert committee recently published their consensus view on the effectiveness of different vaccines on infections, symptomatic disease, and severe disease ^[38].

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.

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.