Coronavirus (COVID-19): ONS Infection Survey – headline results – 24 June 2022

The COVID-19 Infection Survey aims to measure:

• how many people across England, Wales, Northern Ireland and Scotland test positive for a COVID-19 infection at a given point in time, regardless of whether they report experiencing symptoms
• the average number of new positive test cases per week over the course of the study
• the number of people who test positive for antibodies

The regular reporting of Covid-19 Infection Survey (CIS) data for Scotland on the Scottish Government website will stop after the publication on 1 July 2022. The latest CIS data for Scotland can now be found in the Public Health Scotland (PHS) weekly report. The latest estimates for England, Wales, Northern Ireland and Scotland will continue to be available in the ONS weekly bulletin and datasets on the ONS website. If you have any feedback on this change please contact covidinfectionsurvey@gov.scot.

We would like to thank those who have read and used these articles in their personal and professional lives, and provided feedback on its format and content.

All data are provisional and subject to revision.

Main points

In the week 11 to 17 June 2022, the estimated percentage of people testing positive for COVID-19 in Scotland was 4.76% (95% credible interval: 4.16% to 5.40%). There was an increase in the percentage of people testing positive for COVID-19 in Scotland in the most recent week, likely caused by infections compatible with Omicron variants BA.4 and BA.5.

In the same week, it is estimated that 250,700 people in Scotland had COVID-19 at any given time (95% credible interval: 218,900 to 284,400); this equates to around 1 in 20 people (95% credible interval: 1 in 25 to 1 in 19) (see note 1). These estimates contain all variants of COVID-19.

In the week 12 to 18 June 2022, there was an increase in the percentage of people testing positive for COVID-19 in England, Wales and Northern Ireland likely caused by infections compatible with Omicron variants BA.4 and BA.5. Estimates for these nations are as follows:

• in England, the estimated percentage of people testing positive for COVID-19 was 2.50% (95% credible interval: 2.36% to 2.64%), equating to around 1 in 40 people (95% credible interval: 1 in 40 to 1 in 40)
• in Wales, the estimated percentage of people testing positive for COVID-19 was 2.25% (95% credible interval: 1.75% to 2.83%), equating to around 1 in 45 people (95% credible interval: 1 in 55 to 1 in 35)
• in Northern Ireland, the estimated percentage of people testing positive for COVID-19 was 3.26% (95% credible interval: 2.56% to 4.05%), equating to around 1 in 30 people (95% credible interval: 1 in 40 to 1 in 25)

In recent weeks, the estimated percentage of people testing positive for COVID-19 increased for most ages in Scotland.

In Scotland, the percentage of people testing positive for COVID-19 compatible with Omicron BA.1, BA.4 and BA.5 increased in the week 11 to 17 June 2022. Meanwhile the trend in the percentage of people with infections compatible with Omicron variant BA.2 was uncertain.

Modelled estimates of the percentage of people living in private households testing positive for COVID-19 in Scotland

In this publication, the reference week for positivity estimates is 11 to 17 June 2022 for Scotland, and 12 to 18 June 2022 for England, Wales and Northern Ireland. Data are based on confirmed positive test results (see note 13) for COVID-19 of those living in private residential households, excluding those living in care homes or other communal establishments.

The positivity rate is the percentage of people who have tested positive for COVID-19 on a polymerase chain reaction (PCR) test at a point in time. The ONS use current COVID-19 infections to mean testing positive for SARS-CoV-2, with or without having symptoms, on a swab taken from the nose and throat.

It is estimated that in the most recent week (11 to 17 June 2022), the percentage of people in Scotland that had COVID-19 was 4.76%. A 95% credible interval for this figure is 4.16% to 5.40% (see note 4 for further information about credible intervals).

In the same week, the ONS estimate that 250,700 people in Scotland had COVID-19 at any given time. A 95% credible interval for this figure is 218,900 to 284,400. This equates to around 1 in 20 people (95% credible interval: 1 in 25 to 1 in 19).

The percentage of people testing positive for COVID-19 in Scotland increased in the most recent week (Figure 1).

Modelled daily estimates of the rate of COVID-19 infections in private households, and accompanying credible intervals, are represented in Figure 1 by the blue line and grey shading. The model smooths the series to understand the trend and is revised each week to incorporate new test results.

Official reported estimates of the rate of COVID-19 infections in private households are based on the modelled estimate for the midpoint of the most recent week at the time of publication. Official reported estimates, and accompanying credible intervals, are represented in Figure 1 and Figure 2 by the point estimates (blue circles). In Figure 2, pale blue circles denote 14-day weighted estimates while the official reported weekly estimates are denoted by dark blue circles.

Figure 1: Modelled daily estimates and official reported estimates of the percentage of the population in Scotland testing positive for COVID-19 between 7 May to 17 June 2022, including 95% credible intervals (see notes 2,3,4,5,6,14)

 

Figure 2 shows the trend in the official weekly reported estimates of the percentage of those living in private households testing positive for COVID-19 between 3 October 2020 and 17 June 2022. The reference date for the most recent estimate is 14 June 2022.

The estimated percentage of people testing positive for COVID-19 in Scotland increased between late-January and mid-March 2022. The estimate for the week 14 to 20 March 2022 was the highest estimate for Scotland since the survey began. Between late-March and early-May, the estimated percentage of people testing positive in Scotland decreased. In the last two weeks, the percentage of people testing positive for COVID-19 has increased. All official reported estimates displayed in this chart are available in the accompanying dataset on the ONS website.

Figure 2: Official reported estimates of the percentage of the population in Scotland testing positive for COVID-19 between 3 October 2020 and 17 June 2022, including 95% credible intervals (see notes 3,4,5,6,7,14)

 Age analysis of the percentage of people living in private households testing positive for COVID-19 in Scotland

In recent weeks, the estimated percentage of people testing positive for COVID-19 increased for most ages in Scotland (Figure 3).

Figure 3: Modelled daily estimates of the percentage of the population in Scotland testing positive for COVID-19, by reference age, between 7 May to 17 June 2022, including 95% confidence intervals (see notes 2,5,6,8) 

    

Modelling by single year of age leads to a higher degree of uncertainty in comparison with the overall models for Scotland. This is indicated by wider credible intervals and therefore results should be interpreted with caution.

Modelled daily estimates of the percentage of people testing positive for COVID-19 by single year of age in each of the four nations of the UK are available in an accompanying dataset on the ONS website and are presented in an interactive chart in the ONS weekly bulletin.

Modelled estimates of the percentage of people living in private households testing positive for COVID-19 in each of the four nations of the UK

Figure 4 shows modelled daily estimates of the percentage of the population living in private households testing positive for COVID-19 in each of the four nations of the UK.

In the most recent week (11 to 17 June 2022 for Scotland, 12 to 18 June for England, Wales and Northern Ireland), the estimated percentage of people testing positive for COVID-19 increased in all four nations.

Figure 4: Modelled daily estimates of the percentage of the population testing positive for COVID-19 in the four UK nations, between 8 May and 18 June 2022 for Scotland, and 8 May and 18 June for England, Wales and Northern Ireland, including 95% credible intervals (see notes 2,3,4,5,6)

      

Modelled estimates of the proportion of the population living in private households testing positive for COVID-19 for the most recent week can be found in Table 1.

Table 1: Modelled weekly estimates of the percentage of the population testing positive for COVID-19 in the four UK nations, between 11 and 17 June 2022 for Scotland, and 12 and 18 June for England, Wales and Northern Ireland, including 95% credible intervals (see notes 2,3,4,5,6)

 

Nation	Estimated percentage of the population that had COVID-19	Estimated number of people who had COVID-19	Estimated ratio of people who had COVID-19
England	2.50% (2.36% to 2.64%)	1,360,600 (1,285,600 to 1,438,200)	1 in 40 (1 in 40 to 1 in 40)
Northern Ireland	3.26% (2.56% to 4.05%)	59,900 (46,900 to 74,400)	1 in 30 (1 in 40 to 1 in 25)
Scotland	4.76% (4.16% to 5.40%)	250,700 (218,900 to 284,400)	1 in 20 (1 in 25 to 1 in 19)
Wales	2.25% (1.75% to 2.83%)	68,500 (53,300 to 85,900)	1 in 45 (1 in 55 to 1 in 35)

Modelled estimates of the percentage of people living in private households testing positive for COVID-19 by COVID-19 Infection Survey sub-regions

The ONS have created sub-regions across the UK for the purposes of this survey. In Scotland, these sub-regions are comprised of Health Boards. For a list of sub-regions in Scotland, see note 9.

In the most recent week (11 to 17 June 2022), estimates for the percentage of people testing positive were similar for all CIS sub-regions in Scotland. The estimates ranged from 4.65% in CIS sub-region 125 (NHS Greater Glasgow & Clyde) (95% credible interval: 3.96% to 5.42%) and CIS sub-regions 126 (NHS Lothian) (95% credible interval: 3.98% to 5.42%), to 5.03% in CIS Region 123 (NHS Grampian, NHS Highland, NHS Orkney, NHS Shetland and NHS Western Isles) (95% credible interval: 4.31% to 5.93%).

This data is shown in Figure 5, and is also available as a dynamic map (see notes 3,4,5,9,10,11,12).

Sub-regional estimates are based on a different model to the headline estimates, and should not be compared to headline positivity estimates. The sub-regional figures may differ from the headline estimates because they are averaged over a longer time period.

There is a higher degree of uncertainty in our sub-regional estimates because of a smaller sample size in each sub-region relative to their respective national sample. This is indicated by wider credible intervals and therefore results should be interpreted with caution. Overlapping credible intervals indicate that there may not be a true difference between the estimates.

Figure 5: Modelled estimates of the percentage of the population within each CIS sub-region who would have tested positive for COVID-19, between 11 and 17 June 2022 for Scotland, and 12 and 18 June for England, Wales and Northern Ireland (see notes 3,5,9,10,11,12)

  

Number of new COVID-19 infections in Scotland

The ONS provides estimates of incidence rate, a measure of new PCR positive cases per day per 10,000 people in a given time period. The ONS analysis of incidence covers an earlier time period to analysis of the percentage testing positive.

In Scotland, during the week 28 May to 3 June 2022, it is estimated that there were 42.74 new PCR-positive COVID-19 cases per 10,000 people per day (95% credible interval: 35.70 to 50.50) (see note 4). This equates to 22,500 new positive cases in Scotland per day (95% credible interval: 18,800 to 26,600). In the week ending 3 June 2022, the estimated number of new PCR-positive COVID-19 cases per day increased in Scotland.

Modelled daily estimates and official reported estimates of incidence rates are available in the accompanying dataset on the ONS website.

For more information on how estimates of incidence are calculated, please see the COVID-19 Infection Survey methodology article.

Estimated percentages of those testing positive for COVID-19 by variant

The World Health Organization (WHO) have defined names for variants of concern.

Currently, variants under surveillance in the UK are:

• Omicron, including sublineages BA.1, BA.2, BA.3, BA.4 and BA.5
• Delta: B.1.617.2 and its genetic descendants

The ONS publish weekly breakdowns of infections by variant and Cycle-threshold (Ct) values in the accompanying technical dataset on the ONS website. Ct value, reflects the quantity of virus (also known as viral load) found in a swab test. A lower Ct value indicates a higher viral load.

The Coronavirus (COVID-19) Infection Survey: technical dataset includes analysis of the genetic lineages of coronavirus seen in the sequenced samples (see notes 15 and 16). Since March 2022, Omicron BA.2 infections have been the most common in all UK countries. Between 16 May and 12 June 2022, 73.5% of all sequenced COVID-19 infections in the UK were Omicron BA.2 (or its sub-lineages) infections, 15.2% were Omicron BA.5 infections, 9.8% were Omicron BA.4 infections, and 0.2% were Omicron BA.1 (or its sub-lineages) infections.

In response to an increase in the COVID-19 Omicron variants BA.4 and BA.5, the ONS has reintroduced its main variant analysis which is also included in this article. The following main variant analysis is not based on genome sequencing but is based on whether the S gene is detected in the swab tests. The Omicron variants BA.1, BA.4 and BA.5 have changes in one of the three genes that the coronavirus survey swab test detects, which means the S-gene is no longer detected. When there is a high viral load (for example, when a person is most infectious), not detecting the S-gene in combination with detecting the other two genes (ORF1ab and N-genes) is a reliable indicator of these variants. However, as the viral load decreases (for example, if someone is near the end of their recovery from the infection), not detecting the S-gene is a less reliable indicator of these Omicron variants. The Omicron variant BA.2 does not have changes in the S-gene, and therefore all three genes, or the S-gene and either ORF1ab or N, will usually be detected in infections with this variant.

The main variant analysis is for a reference day, and therefore is not directly comparable with the sequence data. It measures the percentage of the population with a positive test compatible with the Omicron BA.1, BA.4 and BA.5 variants or BA.2 variant.

There is a higher degree of uncertainty in estimates for Scotland in comparison to England, as shown by wider confidence intervals. Not all cases that are positive on the ORF1ab and N-genes will be the Omicron BA.1, BA.4 or BA.5 variant, and not all cases that have a detectable S-gene will be the Omicron BA.2 variant.

Figure 6 shows modelled daily estimates of the percentage of the population in Scotland testing positive with infections compatible with the Omicron BA.1, BA.4 and BA.5 variants or BA.2 variant.

In Scotland, the percentage of people testing positive for COVID-19 compatible with Omicron BA.1, BA.4 and BA.5 increased in the week 11 to 17 June 2022. Meanwhile the trend in the percentage of people with infections compatible with Omicron variant BA.2 was uncertain.

Figure 6: Modelled daily estimates of the percentage of the population in Scotland testing positive with infections compatible with Omicron BA.1, BA.4 and BA.5 and compatible with Omicron BA.2, between 7 May and 17 June 2022, including 95% credible intervals (see notes 2,4,5,15,16,17)

The main variant analysis by UK country and by regions of England are available in the accompanying technical dataset on the ONS website.

More information on how the ONS measures variants from positive tests on the survey can be found in the Understanding COVID-19 variants blog. The COVID-19 Infection Survey methodology article gives more detail about how the ONS sequence the virus’ genetic material.

Whole Genome Sequencing is produced by Wellcome Trust Sanger Institute and analysis is produced by research partners at the University of Oxford. For more details please see the ONS weekly bulletin.

Further information

This article is published at 12:00 noon, at the same time as the Office for National Statistics (ONS) release their bulletin which contains estimates for England, Wales, Northern Ireland and Scotland. This is later than the standard release time for official statistics of 09.30 am and has been approved by the Office for Statistics Regulation.

Early management information from the COVID-19 Infection Survey is made available to government decision-makers to inform their response to COVID-19. Occasionally, the ONS may publish figures early if it is considered in the public interest. The ONS will ensure that it pre-announces any ad hoc or early publications as soon as possible. These will include supporting information where possible to aid user understanding. This is consistent with guidance from the Office for Statistics Regulation (OSR).

An updated antibodies dataset containing data about the proportion of people living in private households in Scotland who would have tested positive for COVID-19 antibodies was published on 15 June 2022 on the ONS website. An article containing main points of these estimates was published on the Scottish Government website. This release includes modelled estimates of the percentage of adults (aged 16 years and above) in Scotland, and children (aged 8 to 15 years) in Great Britain, with antibodies against SARS-CoV-2.

Analysis on the percentage of people testing positive that reported COVID-19 symptoms was published on 22 June 2022 on the Scottish Government website and the ONS website. The latest analysis on how often individuals in Scotland are reporting social contact with other people outside their own household (either socially distanced or physical contact) was published on 11 May 2022 on the Scottish Government website and the ONS website. The article published on 22 June 2022 on the ONS website also includes UK level analysis on reinfections with COVID-19, and risk factors of reinfections with COVID-19. The latest analysis on characteristics associated with testing positive was published on 25 May 2022 on the ONS website.

An article on the prevalence of ongoing symptoms following COVID-19 infection in the UK was published on the ONS website on 1 June 2022. This release includes estimates of the prevalence of self-reported “long COVID”, and the duration of ongoing symptoms following confirmed COVID-19 infection, using UK data to 1 May 2022.

An article on the cumulative number of people in the UK who have tested positive for COVID-19 since the start of the survey was published on 22 April 2022 on the Scottish Government Website and ONS website. This release includes modelled cumulative percentages of the population who have tested positive for COVID-19 during the survey period by country.

An article on characteristics associated with third vaccination uptake was published on 21 April 2022 on the ONS website. This release includes modelled likelihood of receiving a third vaccination against COVID-19 by various screened characteristics, and age groups, for the UK.

How this data can be used

The data in this bulletin can be used for:

• estimating the number of positive cases among the population living in private households, including cases where people do not report having any symptoms
• identifying differences in numbers of positive cases between UK countries and different regions in England
• estimating the number of new cases and change over time in positive cases

The data cannot be used for:

• measuring the number of cases and infections in care homes, hospitals and/or other communal establishments
• providing information about recovery time of those infected

The results in this article are:

• provisional and subject to revision
• based on infections occurring in private households
• subject to uncertainty; a credible or confidence interval gives an indication of the uncertainty of an estimate from data analysis

Methodology

The results are based on nose and throat swabs provided by participants to the study, obtained from fieldwork which started in Scotland on 21 September 2020.

The results are for private households only, and do not apply to those in hospitals, care homes or other communal establishments. The population used in this analysis relates to those living in private households aged two years and over.

In Scotland, in the latest six-week period (7 May to 17 June 2022), there were 34,203 swab tests from 27,866 people, with a total of 1,008 positive samples in 998 people from 824 households. In the latest two-week period (4 to 17 June 2022), there were 8,908 swab tests from 8,908 people, with a total of 370 positive samples in 370 people from 294 households.

The COVID-19 Infection Survey bulletins and datasets available on the ONS website also include results for England, Wales and Northern Ireland.

The Welsh Government and the Department of Health in Northern Ireland also publish results from the COVID-19 Infection Survey for Wales and Northern Ireland respectively:

• Welsh Government
• Department of Health in Northern Ireland

Further details on methodology can be found in the COVID-19 Infection Survey methodology article.

Notes

1. The ratios presented are rounded to the nearest 100 if over 1,000, to the nearest 10 if under 1,000, to the nearest 5 if under 100 and to 1 if under 20. This may result in credible intervals that appear to be similar to the estimated average ratio. These ratios do not represent a person's risk of becoming infected, since risk of infection depends on a number of factors such as contact with others or whether a person has been vaccinated.
2. There is more uncertainty around estimates for the latest three reported days (as shown by the vertical dashed line), as lab results for this period are still being processed at the time of publication. Additional swab tests that become available after this publication are included in subsequent models, meaning that modelled estimates can change as additional data is included.
3. Modelled estimates are not directly comparable with the 14-day weighted estimates provided in the accompanying dataset on the ONS website. The 14-day weighted estimates underpin the modelled estimates and are provided for context. 14-day weighted estimates are not directly comparable with the weekly modelled estimates due to the differing methodology, however they have been included in Figure 2 as they were reported as the official estimates for Scotland before the weekly modelled estimates became available.
4. The model used to provide these estimates is a Bayesian model: these provide 95% credible intervals. A credible interval gives an indication of the uncertainty of an estimate from data analysis. 95% credible intervals are calculated so that there is a 95% probability of the true value lying in the interval. A credible interval gives an indication of the degree of uncertainty of an estimate, showing the precision of a sample estimate.
5. There is a higher degree of uncertainty in estimates for Wales, Northern Ireland and Scotland relative to England. This is indicated by wider credible intervals and therefore results should be interpreted with caution.
6. The blue line and shading represent the modelled trend and credible intervals based on the latest data. The point estimates and error bars represent the official weekly estimates and their credible intervals, which are based on the modelled estimate for the midpoint of the week at the time of publication.
7. As there was no publication on 15 January 2021 there are no official estimates available for the week ending 9 January 2021. However, ONS conducted some additional analysis to assess what the estimate may have been, therefore this estimate is included in Figure 2, shown in light grey.
8. A confidence interval gives an indication of the degree of uncertainty of an estimate, showing the precision of a sample estimate. The 95% confidence intervals are calculated so that if we repeated the study many times, 95% of the time the true unknown value would lie between the lower and upper confidence limits. A wider interval indicates more uncertainty in the estimate.
9. The table below contains the composition of each CIS region in Scotland, by Health Board and Local Authority area. Local Authority areas map to the Health Board areas.

CIS Region Code	Health Boards	Local Authority Areas
123	NHS Grampian, NHS Highland, NHS Orkney, NHS Shetland and NHS Western Isles	Aberdeen City, Aberdeenshire, Argyll & Bute, Highland, Moray, Na h-Eileanan Siar, Orkney Islands, Shetland Islands
124	NHS Fife, NHS Forth Valley and NHS Tayside	Angus, Clackmannanshire, Dundee City, Falkirk, Fife, Perth & Kinross, Stirling
125	NHS Greater Glasgow & Clyde	East Dunbartonshire, East Renfrewshire, Glasgow City, Inverclyde, Renfrewshire, West Dunbartonshire
126	NHS Lothian	City of Edinburgh, East Lothian, Midlothian, West Lothian
127	NHS Lanarkshire	North Lanarkshire, South Lanarkshire
128	NHS Ayrshire & Arran, NHS Borders and NHS Dumfries & Galloway	Dumfries & Galloway, East Ayrshire, North Ayrshire, Scottish Borders, South Ayrshire

10. Sub-regional estimates are based on a different model to the headline estimates. Our sub-regional estimates are calculated as an average over a thirteen-day period and should not be compared to the headline positivity estimates which are for a single reference date. Therefore, the sub-regional figures may differ from the headline estimates because they are averaged over a longer time period. If a trend is changing quickly, the figures shown in Figure 5 may not reflect the change we are seeing in our headline estimates.
11. To provide more precision to sub-regional estimates, ONS updated its method on 26 November 2021 to model the last 13 weeks of data instead of the last 7 weeks of data, as in previous releases.
12. The colour scale on this map was altered in the publication on 24 June 2022 to accommodate increased infection levels. Therefore, colour scales in sub-regional charts are not comparable across bulletins.
13. Estimates are based on confirmed positive test results. The remaining swabs are either negative and included in analysis, or inconclusive and not included in analysis. Some swabs are test failures, which also are not included in analysis. The impact of excluding inconclusive results on estimates of positive infections is likely to be very small and unlikely to affect the trend.
14. Due to the timeliness of the data received from the laboratories and occurrence of public holidays there are gaps and overlaps between some of the official estimates, this does not impact the comparability of these estimates.
15. Omicron BA.1, BA.4 and BA.5 variant-compatible positives are defined as those that are positive on the ORF1ab-gene and N-gene, but not the S-gene. This group includes Omicron BA.1.1.
16. Omicron BA.2 variant-compatible positives are defined as those that are positive on the S-gene, in addition to one or both the ORF1ab-gene and N-gene.
17. Data should be treated with caution. Not all infections positive on the S-gene will be the Omicron BA.2 variant, and some infections with pattern ORF1ab+N will also be the Omicron BA.2 variant where the S-gene was not detected for other reasons, such as low viral load.