Publication - Research and analysis

Coronavirus (COVID-19): state of the epidemic - 30 April 2021

Published: 30 Apr 2021

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

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Contents
Coronavirus (COVID-19): state of the epidemic - 30 April 2021
Coronavirus (COVID-19): Analysis : State of the Epidemic in Scotland – 30th April 2021

15 page PDF

1.2 MB

Coronavirus (COVID-19): Analysis : State of the Epidemic in Scotland – 30th April 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 the 29 April 2021 on COVID-19 in Scotland. This updates the previous publication published on 23 April 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 level, at a local level and how Scotland currently compares to the rest of the UK. It looks at the vaccination program in Scotland and the effects which 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.

Key Points

  • The reproduction rate R in Scotland is currently estimated as being between 0.8 and 1.0. This is higher than last week.
  • An average of 181 cases were reported per day in the 7 days to 29 April, which is an 18% decrease in reported cases since the 22 April.
  • There were 25 weekly cases per 100,000 in the week to 26 April, which is a decrease since last week. This compares to 302 weekly cases per 100,000 on 8 January and is similar to the weekly case rate observed on 14 September.
  • Case rates saw the sharpest decrease in those aged 20-39, however a slight increase in case rates in those aged 00-19 this week.
  • The estimated proportion of people becoming infected with Covid in Scotland has continued to decrease in the most recent week and is currently above England, Northern Ireland and Wales as determined through the latest weekly ONS survey.
  • Latest modelled estimates suggest there are currently between 1 and 15 new daily infections per 100,000 people in Scotland.
  • Deaths involving coronavirus have declined most in those aged 75-84 over the 3 weeks to 25 April, having gone down by 69%. Deaths in those aged 15-44 and 65-74 have declined by 50% over the same period.
  • Average daily deaths per 100,000 population in Scotland (0.03) are level with England, Wales and Northern Ireland (0.03 each).
  • North Lanarkshire and Moray currently have the highest weekly case rates in Scotland reporting 47 and 46 cases per 100,000 respectively in the last week, while Highland, Argyll and Bute, Aberdeenshire, Orkney, Angus, Scottish Borders and Midlothian reported fewer than 10 weekly cases per 100,000 each in the same time. Shetland and Na h-Eileanan Siar had 0 cases per 100,000 in the last week.
  • At a national level hospital bed and ICU occupancy are projected to fall over the next few weeks, but these both may plateau or increase as a result of schools reopening and other relaxations of non-pharmaceutical interventions.
  • Over 2.7 million people in Scotland have been given a first vaccine against SARS-CoV-2, and over 1.1 million have now received a second dose.
  • The current UK variant of concern remains the dominant strain.

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, 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 (published on 29 April)[2] was between 0.8 and 1.0 (Figure 1), with a growth rate of between -4% and -1%.

Figure 1. R in Scotland over time
The R number has varied over the pandemic with the estimated range moving above 1 in Autumn 2020 and January 2021. For the number of infectious people to fall we need to keep the R number consistently below 1. The latest R value for Scotland (published on 29th April) has increased to between 0.8 to 1.0 compared to the previous weeks estimate of between 0.7 and 0.9 (Figure 1), with a growth rate of between -4% and -1% implying that the number of infectious people is still falling.

As Scotland started to move out of national level stay at home measures, an average of 181 cases were reported per day in the 7 days to 29 April. This is an 18% decrease from the daily average cases recorded a week earlier to 22 April[3]. Average daily cases reported are now under a tenth of the peak of 2,323 in the week to 7 January. Our current position is 25 weekly cases per 100,000 in the week to 26 April[4]. This compares to 302 weekly cases per 100,000 on 8 January and is similar to the weekly case rate observed on 14 September (see Figure 2)[4].

Figure 2. Seven day case rate for Scotland by specimen date. Refers to PCR testing only.
The weekly case rate of diagnosed infection is defined as the number of newly reported, laboratory confirmed cases of SAR-CoV-2 per 100,000 population. This case rate rose from a low of 24.7 in September to 170.1 in October. It then reduced and levelled off at just over 100 by the beginning of December. At the end of December it rose sharply to just over 300 at the start of January. It has been decreasing since then but during March there was a small increase and then it plateaued for two weeks. It has started to decrease again in the last three weeks. The weekly case rate is 25 as at 26th April and is now similar to the weekly case rate observed on 14 September.

Case rates saw the sharpest decline in those aged 20-39, however a slight increase in 7 day cases per 100,000 in those aged 00-19 this week (Figure 3).

Figure 3. Seven day case rate in Scotland by age group by specimen date [5]. Refers to PCR testing only.
Figure 3 shows the seven day cases per 100,000 for five different age bands over time.  Each age band shows a similar trend with a peak in cases in January, with the 20-39 age band having the highest case rate and the 00-19 age band having the lowest case rate.  Cases rates reduced in all age group from this peak. Case rates have decreased most in those aged 20-39 this week, and increased slightly in those aged 00-19.

Not everyone who has the virus will be tested, as many people do not realise they have COVID, or have mild symptoms and do not come forward. Latest modelled estimates suggest there are currently anywhere between 50 and 800 people infected in Scotland each day[2]. This means that as of 28 April there were between 1 and 15 new daily infections per 100,000 people.

The number of people in hospital with confirmed Covid for less than 28 days is declining. After peaking at 2,053 on 22 January, this figure has decreased and as of 29 April there were 70 patients in hospital with COVID-19. In addition, there was a fall in daily hospital admissions for people with Covid from a peak of 241 on 11 January to 8 on 25 April[6].

There were 23 deaths registered where Covid was mentioned on the death certificate in the week to 25 April. This is a 4% decrease on the week before, and 97% lower than the peak in April 2020 (663 deaths). The proportion of deaths in care homes has decreased from 36% in mid-December to 13% of total deaths in the week to 25 April. This has also increased from 8% in the week to 22 March, but this needs to be interpreted with caution due to low numbers. Deaths involving coronavirus have declined most in those aged 75-84 and have gone down by 69% in this age group over the 3 weeks to 25 April[7] (Figure 4). Deaths in those aged 15-44 and 65-74 have declined by 50% over this period. Deaths have remained low in those aged 85+ with no change observed in the 3 week period, whereas a 17% increase (from 6 to 7 deaths) has been recorded amongst 45-64 age group in the 3 weeks to 25 April.

Figure 4. Deaths by age group (weekly total by week beginning, NRS) [7]
This figure shows the number of deaths over time for seven different age groups. In April 2020 the number of deaths in the four age groups for 45+ reached a peak with the highest number of deaths being in the 85+ group.  Deaths then declined steeply and the number of deaths were very low in all age groups during July to September.  In October the number of deaths started to increase and then plateaued during November and December for the four age groups 45+. At the end of December deaths rose steeply again to another peak in January with the highest deaths being in the 85+ group. The number of deaths has since declined steeply with the largest decrease in the 85+ age group observed first followed by a sharp decline in the 75-84 age group. Over the last three weeks to 25 April, deaths is those aged 75-84 have gone down by 69%. Similarly in those aged 15-44 and 65-74 deaths have gone down by 50% and no change in the 80+ age group. Note that the number of deaths in all age groups is now low. Deaths in the under 44s have remained very low throughout the whole period.

How Scotland compares with the rest of the UK

The latest ONS survey estimates that the proportion of the population infected in the community in Scotland (0.16% people currently testing positive for Covid-19 from 18-24 April) has continued to decrease in the most recent week. However this is still above England (0.10%), Northern Ireland (0.11%) and Wales (0.06%). In the week to the 24 April the estimated rate of community infection was 1 in 640 people in Scotland, compared to 1 in 1,010 for England, 1 in 1,570 for Wales and 1 in 940 for Northern Ireland[8]. Average daily deaths in Scotland (0.03 per 100,000 in the week to 29 April) are level with England, Wales and Northern Ireland (0.03 each). The Coronavirus Infection Survey estimated that in the week to 11 April, 57.8% of the adult population in Scotland would have tested positive for antibodies against Covid-19, as a result of having the infection in the past or being vaccinated. This compares to 68.3% in England, 61.0% in Wales, and 62.5% in Northern Ireland[9].

Situation by local authority within Scotland

North Lanarkshire and Moray currently have the highest case rates in Scotland with 47 and 46 weekly cases respectively being reported per 100,000 in the week to 26 April. There was a 21% decrease in cases per 100,000 in North Lanarkshire from the week to 19 April, whereas Moray has recorded a 38% increase in case rates in the same time[4]. There are mostly moderate and low levels of cases across Scotland, with moderate levels of cases observed across the central belt (Figure 5). Highland, Argyll and Bute, Aberdeenshire, Orkney, Angus, Scottish Borders, and Midlothian each had fewer than 10 weekly cases per 100,000 in the week to 26 April. Shetland and Na h-Eileanan Siar had 0 cases per 100,000 in the last week[4].

Figure 5. 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 across Scotland’s Local Authorities. The colours range from green with under 1 weekly case, through light blue with 1 – 20 weekly cases, dark blue 20-50 weekly cases,  purple 50-150 weekly cases and red with over 150 weekly cases per 100,000. North Lanarkshire has the highest case rate in Scotland with 47 weekly cases being reported per 100,000, followed by Moray with 46 weekly cases per 100,000 in the week to 26th April. Na h-Eileanan Siar and Shetland are showing as green with no cases per 100,000 population. All other Local Authorities are showing as light or dark blue.

The most recent modelling predicts that for the week ending 15 May, there are no local authorities with at least a 75% probability exceeding 50 cases per 100,000 population (Figure 6)[2]. This is unchanged from last week.

Figure 6. Maps of probability of Local Authorities exceeding 50, 100, 300 and 500 cases per 100,000 population in the period 9-15 May 2021 [10]
This figure shows the probability of Local Authorities having more than 50, 100, 300 and 500 cases per 100,000 population. Hotspot is defined as an area that is predicted to exceed the cases threshold. The most recent modelling predicts that for the week ending 15 May, there are no local authorities with at least a 75% probability exceeding 50 cases per 100,000 population.

Children and Education

Children in early learning and childcare and those in primaries 1-3 went back to school or nursery on 22 February, and all children in primaries 4-7 went back on the 15 March. There has also been a phased return to secondary schools, with some Senior Phase (S4-S6) pupils returning to school on a part-time basis to attend practical lessons from the 22 February and all secondary school pupils (S1-S6) returning on a part-time basis from the 15 March. Most children and young people returned to full time education on the 12th or 19th April.

Over the last week there was a slight increase in the total number of COVID- 19 cases in children, which has gone up from 366 cases in the week to 18 April to 388 cases in the week ending 25 April. This is still low compared to all other weeks since mid-September. 7 day cases per 100,000 have increased slightly in the over 12 year olds in the week ending 25 April, and the highest proportion of cases still observed in those under 12 (159 cases). However, there was a fall in 7 day cases per 100,000 in those aged 5-11 (Figure 7)[11]. There has been an increase in testing amongst all age groups, except for 18-19 year olds, in week ending 25 April. Test positivity rates have increased in those aged 16-19, however decreased in those aged 2-15 the same period[11]. Overall, the proportion of school, early learning and childcare settings with incidents remains low.

Figure 7. Seven day case rate in Scotland by age group by specimen date for children. Refers to PCR testing only.
This figure shows the 7-day case rate of school pupils who tested positive for COVID-19, grouped in five age groups, during the period 14 February 2021 to 18 April 2021. The rates for all age groups have varied over time with a sharp increase in rates for the 18-19 age group in the middle of February. The rates for most age groups have decreased in the week to 25 April, with the sharpest fall in 7 day cases per 100,000 observed in those aged 5-11 and increased slightly in the over 12 year olds.

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[2]. From this survey we can say that contacts are higher than seen during the lockdown period (averaging around 3 daily contacts) with a current level of 3.3 daily contacts. Contacts within the work and school setting have shown a decrease in the last two weeks by 32% and 88% respectively. Mean contacts within the 'other' setting (contacts outside of the school, home or work settings) have increased by approximately 11% over the same period. Individuals aged 60 and over have increased their contacts in the last two weeks, while average contacts for those aged under 60 have remained level or have shown a decrease.

Self-reported compliance with the current regulations and guidance has decreased since January but remains at a high level. On 27-28 April, 72% of people reported ‘complete’ or ‘almost complete’ compliance[12].

Hospital bed and ICU occupancy are projected to fall over the next few weeks, but these both may plateau or increase as a result of schools reopening and other relaxations of non-pharmaceutical interventions (Figure 8)[2].

Figure 8. Medium term projections of modelled ICU bed demand, from Scottish Government modelling [13]
shows the projections of modelled demand for ICU beds required over time and displays a better and worst case scenario which are related to the success of the vaccine roll out. The actual number of beds required has been following the better case scenario so far with the projected demand to continue to fall in the next few weeks but may plateau or increase as a result of schools reopening and other relaxations of non-pharmaceutical interventions. Both scenarios are based on current vaccine roll-out plans and efficacy assumptions. The difference between the two projections reflects uncertainty about behaviour and compliance as interventions are relaxed.  Actual data does not include full numbers of CPAP. ICU bed actuals include all ICU patients being treated for Covid-19 including those over 28 days

Vaccinations are continuing across the priority groups and over 61% of the adult population in Scotland has now been vaccinated with the first dose[4]. The first vaccines were administered on Tuesday 8 of December and 2,796,810 had received their first dose by 29 April 2021, a 1.5% increase from the 22 April[3]. By the 29 April over 35,000 residents in care homes had received their first vaccination along with over 53,000 care home staff. In older adult care homes just over 90% of residents have now received their second dose. By age group, almost 100% of individuals aged 55+ and 91% of those aged 50-54 had received their first vaccination (Figure 9). 91% of the over 80s, 84% of those aged 75-79, 77% of those aged 70-74 and 50% of those aged 65-69 have received their second dose. Overall, 1,184,629 (26%) of those aged 16 and over had received their second dose by 29 April[6]. There are continual decreasing hospitalisations and deaths among those groups vaccinated first (Figure 4).

Figure 9. Estimated percentage of people vaccinated by 29 April 2021
The first vaccines were administered on Tuesday 8 of December and 2,796,810 had received their first dose by 29th April 2021, a 1.5% increase from the 22nd April. For the ten age groups identified, six groups have more than 98% vaccinated (everyone age 55+) and for age groups 60-64 and 70-79, 100%, for age group 50-54, 91%, have been vaccinated. 91% of over 80s, 84% of those aged 75-79, 77% of the 70-74 year olds and 50% of the 65-69 year olds have received their second dose by 29th April.

The proportion of people surveyed who said they would be likely to be vaccinated for COVID-19 remains high. 63% of all respondents have already received at least their first vaccine dose. Of those not vaccinated, 74% report they are likely to be vaccinated when a vaccine becomes available to them[14].

How the virus is changing

The variant of the virus commonly known as the UK variant (VOC-20DEC-01) remains the dominant strain in Scotland[15]. This new variant of Covid is more transmissible[16]. It is likely that infection with this variant is associated with an increased risk of hospitalisation and death compared to infection with non-VOC viruses[17].

Other variants of concern (VOCs) are being monitored by sequencing of SARS-CoV-2 samples (Figure 10). To date there are four VOCs and nine variants under investigation[18]. Up to 28 April, there have been 34 genomically confirmed cases of the variant VOC-20DEC-02 (first seen in South Africa) detected in Scotland, (up two since the previous week). There have been 10 confirmed cases of the variant VOC-21JAN-02 (first identified from Brazil) which is an increase of 1 since last week. There have also been a number of cases of other variants, which are currently under investigation, including 30 cases of VUI-21FEB-03 (first seen in Nigeria) (up 2 from last week) and 13 cases of VUI-21APR-01 (first identified in India), an increase of 8 in the past week. There is some 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[19][20][21].

Figure 10. Variants detected in Scotland by sequencing (data up to 28 April and reported weekly [22])
The figure shows the number of cases for the variants of concern and variants of interest detected by sequencing in Scotland during the period 25 January 2021 to 28 April 2021. VOC-20DEC-02, first found in South Africa, has been increasing steadily since late January from 3 cases initially and is currently at 34 cases. VUI-21FEB-03, first identified in Nigeria, has seen a rapid increase since mid-March to 30 genomically confirmed cases to 28 April. There are also 13 cases of VUI-21APR-01, first identified in India.

Next steps

The Scottish Government continues to work closely with Public Health Scotland to monitor the course of the epidemic using several data sources. Each week this report will provide an overview of 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 problem 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