Transparency data

Weekly statistics for rapid asymptomatic testing in England: 11 March to 17 March 2021

Updated 23 April 2021

Applies to England

Introduction

This statistical publication aims to provide information on rapid testing for people without COVID-19 symptoms in England. This includes:

• the number of LFD tests conducted in England by test result
• the number of LFD tests conducted in England by region
• the number of LFD tests conducted in England in education settings
• the number of LFD and PCR tests conducted in England in care homes

This publication focuses on rapid testing using lateral flow device (LFD) tests, however polymerase chain reaction (PCR) tests are included where appropriate, either for comparison or where regular asymptomatic PCR testing is used. All data used in the report can be found in the ‘Tests conducted’ data tables on the weekly collection page. This includes information on both LFD and PCR tests at lower-tier local authority level.

The figures in this report are not deduplicated and refer only to the number of tests taken, not the number of people tested. Because people can have more than one test, the data should not be compared with prevalence or case positivity rates.

The figures in this report include LFD tests which were registered through the National Testing Programme digital infrastructure. They do not currently include LFD tests conducted where the tests were not registered via this route. LFD tests for the majority of secondary care NHS staff and some testing within the private sector testing are therefore not included.

See the About this data section below for more information.

Background

Types of tests

PCR tests

PCR tests check for the genetic material of the coronavirus in the sample, which is taken using a swab and is processed in a lab via a polymerase chain reaction (PCR). This type of test is predominantly used for:

• anyone who has symptoms
• to confirm a positive LFD test result in certain use cases, including:
  • self-reporting LFDs^{[footnote 1]}
  • cross channel hauliers
• regular asymptomatic testing in social care

Lateral flow device tests

LFD tests, often referred to as rapid tests, test for the presence of proteins called ‘antigens’ which are produced by the virus. They are swab tests that give results in 30 minutes or less, without the need for processing in a laboratory. These tests are primarily used for those who do not have symptoms.

From 21 October 2020, LFD tests were made available in limited capacity except where rapid testing pilots were conducted. Since then, their availability has expanded to a broader range of settings.

Rapid testing for people without symptoms

Rapid testing using LFD tests is currently being offered to people who do not have symptoms, in a range of different settings.

Some LFD testing is carried out at asymptomatic test sites, which are deployed in a range of community settings such as universities, schools, care homes and workplaces. They are also set up by local authorities as part of the community testing program. Testing at these sites is assisted: a person will take a swab test under the supervision of a trained operator who then processes the test then reads and records the result.

Some LFD testing is carried out entirely by individuals themselves (that is an individual takes their own test, unassisted, and reports their own result), however in these specific situations (see the Types of tests section above) if a positive test result is returned the individual is required to take a confirmatory PCR test. For more information see understanding lateral flow tests for people without symptoms.

LFD tests conducted, England^{[footnote 2]}

The number of LFD tests conducted has been increasing overall since their introduction in October 2020. In the latest week (11 March to 17 March), 7,648,022 LFD tests were conducted. The number of LFD tests conducted has risen sharply in each of the latest two weeks, which coincides with return of secondary students to school.

In comparison, in the latest week 1,045,581 PCR tests were conducted. This is the eighth successive week for which more LFD tests were conducted than PCR tests. Previously the number of PCR tests conducted had always been higher than LFD tests. This reflects the increasing use of LFD tests, as well as a decrease in symptomatic people taking a PCR test due to decreasing COVID-19 prevalence.

PCR and LFD tests have different uses and are therefore applied in different situations (see the Types of tests section above for more information). The primary purpose of rapid LFD testing is to identify people with COVID-19 who do not have symptoms. As the number of LFD tests conducted increases, more asymptomatic positive cases are identified earlier and therefore they are less likely to transmit the virus to their contacts.

Of the LFD tests conducted in the latest week, 8,279 tests returned a positive result, and 7,631,131 tests returned a negative result. Since LFD tests were introduced, 111,388 positive results and 31,036,553 negative results have been reported.

Figure 1: number of LFD and PCR tests conducted, England

This data can be found in the ‘table_1’ and ‘table_2’ tabs of the ‘Tests conducted: 28 May 2020 to 17 March 2021 data tables’ on the weekly collection page.

LFD tests conducted by region, England

The number of LFD tests conducted has increased steeply across all regions in the latest week, continuing the upward trend from the previous week. This follows a decrease between 11 February and 17 February which coincided with half term. Between 11 March and 17 March 2021, the most LFD tests were conducted in the South East followed by the North West.

Figure 2: LFD tests conducted by region, England^{[footnote 3]}

This data can be found in the ‘table_4’ tab of the ‘Tests conducted: 28 May 2020 to 17 March 2021 data tables’ on the weekly collection page.

LFD tests conducted in education settings, England

The rapid testing operation has been rolled out differently across the different education settings, as summarised in the table below. For more information see the NHS Test and Trace statistics methodology.

Setting	Testing started	Frequency	Group tested
Primary schools, school-based nurseries and maintained nursery schools	18 January 2021 1 March 2021	Twice a week Twice a week	Staff Households and bubbles of staff and students
Secondary schools and colleges	4 January 2021 1 March 2021 8 March 2021	Once a week then increased to twice a week Twice a week 3 tests on return (spaced 3 to 5 days apart) then twice a week	Staff and students* Households and bubbles of staff and students Students
Higher education	27 November 2020 25 January 2021	Twice before leaving and twice on return Twice a week	Staff and students Staff and students

*Students in this time period only included children of critical workers and those in vulnerable groups who were currently attending school.

Staff, students, household bubbles and support bubbles who test positive after using a home LFD test kit are required to take a confirmatory PCR test. Individuals who test positive from an LFD test taken at an on-site test centre do not require a confirmatory PCR. For more information on the testing methods for the different phases of education see the NHS Test and Trace statistics methodology.

LFD tests conducted by phase of education

The number of LFD tests conducted within primary schools, school-based nurseries and maintained nursery schools increased substantially between 14 January 2021 and the beginning of February to over 700,000 tests in a week. Between 11 and 17 February the number of tests conducted decreased compared to the previous week, which coincided with half term. In the latest week the number of tests conducted has continued to increase to 885,369 tests. 1,398 positive test results were returned in the latest week within primary schools and nurseries, an increase from 756 positive results in the previous week.

Similarly, within secondary schools and colleges, the number of LFD tests conducted increased gradually since the week commencing 31 December 2020 to over 400,000 in the week commencing 4 February. The number of tests conducted decreased between 11 and 17 February compared with the previous week, which coincided with half term. In the latest week, the number of tests has increased to 5,678,955 tests, a continuation of steep increase in testing seen since the week commencing 4 March when students returned to school. The number of positive test results has increased for 4 consecutive reporting weeks, up to 3,082 positive results in the latest week.

This week the methodology for tests not registered has improved and these tests can now be attributed to a phase of education.

Almost all tests not registered are associated with secondary schools and colleges as they arise due to on-site testing. The number of tests not registered by other phases of education are very small and are therefore not included in this report. From week commencing 11 March, the total number of LFD tests taken in secondary schools and colleges now includes these unregistered tests and the data for previous weeks has been revised accordingly. The full breakdown of tests registered and not registered in secondary schools and colleges is available in ‘table 6’ of the ‘Tests conducted: 28 May 2020 to 17 March 2021 data tables’ on the weekly collection page.

103,891 LFD tests were conducted in the latest week in higher education, which is a slight increase from 92,175 tests in the previous week. The number of LFD tests conducted in higher education peaked between 3 December to 9 December 2020 which coincides with students getting tested to enable them to travel home for the winter break. 104 positive test results were returned in higher education in the latest week, similar to the previous week.

The number of positive test results is not published as a proportion of the total tests conducted due to the data quality. In addition, because there are differences in the testing operation between the different phases of education, they cannot be directly compared. See the Data quality section below for more information.

Figure 3: number of LFD tests conducted in education, by phase of education, England

This data can be found in the ‘table_6’ tab of the ‘Tests conducted: 28 May 2020 to 17 March 2021 data tables’ on the weekly collection page.

LFD tests conducted by staff, students, household bubbles and support bubbles

In the latest week 626,755 LFD tests were taken by staff in secondary schools, in comparison with 756,227 tests taken by staff in primary schools, school-based nurseries and maintained nursery schools. The number of tests conducted by primary, nursery and secondary school staff has continued to increase over the last 4 reporting weeks. This follows a low number of tests in the week commencing 11 February, coinciding with half-term.

In the latest week, 3,867,007 tests were taken by students in secondary schools. This has increased over the last 4 reporting weeks with a steep increase observed since week commencing 4 March, coinciding with students return to school.

216,900 tests were taken by individuals that belong to a household bubble of a student or staff member at school or nursery and 20,634 were taken by individuals in their support bubbles. The number of tests conducted by household and support bubbles has increased since they were first reported in the previous week.

Figure 4: number of LFD tests conducted by staff and students in secondary schools, England

This data can be found in the ‘table_7’ tab of the ‘Tests conducted: 28 May 2020 to 17 March 2021 data tables’ on the weekly collection page.

Tests conducted and registered to care home settings, England

Asymptomatic testing, using both rapid LFD tests and PCR tests has been rolled out differently across different care home settings and their residents, staff and visitors, as summarised in the table below.

The number of tests conducted in care homes includes staff, residents and visitors tested via test kits directly sent to the care home which were registered. It will not include care home staff residents, or visitors who are tested via a different route, for example at a regional or local test site or a mobile testing unit or tests that were not registered.

For more information see the NHS Test and Trace statistics methodology.

Setting	Dates	Frequency	Test kit
Care home residents	7 June 2020 to present 22 Feb 2021 to present	Monthly In the event of an outbreak: day 1 and between days 4 to 7 In the event of an outbreak: day 1 and between days 4 to 7 at HPT discretion	PCR LFD
Care home staff	7 June 2020 to present 23 Dec 2020 to present	Weekly In the event of an outbreak: day 1 and between days 4 to 7 Twice weekly In the event of a positive case in the care home: daily until 5 days without a positive	PCR LFD
Care home indoor visitors	8 Mar 2021 to present 8 Mar 2021 to present 2 Dec 2020 to present*	Weekly – essential care givers Twice weekly – essential care givers On arrival	PCR LFD LFD
Care home visiting professionals – CQC inspectors	14 Dec 2020 to present 22 Mar 2021 to present	Weekly Before a visit	PCR LFD
Care home visiting professionals – all other professionals	14 Dec 2020 to present	On arrival, unless part of a regular testing regime and can provide proof of a negative result within 72 hours	LFD

*Close contact visits with LFD testing began on 2 December 2020 but ceased on 6 January 2021 because of the national lockdown. Throughout the period of national restrictions, visits were limited to outdoors, in visiting pods, or with a substantial screen; as well as those in exceptional circumstances such as end of life.

PCR and LFD tests conducted and registered to care home settings, England

The number of PCR tests conducted within care homes increased overall from 40,000 tests in the week commencing 25 June 2020 to over 550,000 tests in the week commencing 7 January 2021. This has decreased across the last 2 months to 431,791 tests in the latest week (11 to 17 March 2021) as prevalence and the number of outbreaks has reduced.

The number of LFD tests conducted within care homes increased steeply from the week commencing 10 December 2020 to over 560,000 tests in the week commencing 4 February 2021. Since then, the number of LFD tests conducted has decreased slightly to 536,257 tests in the latest week (11 to 17 March 2021) as prevalence and the number of outbreaks has reduced.

The week commencing the 11 March 2021 was the eighth successive week for which more LFD tests were conducted than PCR tests. Previously the number of PCR tests conducted had always been higher than LFD tests. This reflects the increasing use of LFD tests, as well as a decrease in symptomatic people taking a PCR test due to decreasing COVID-19 prevalence.

Of the LFD tests conducted in the latest week (11 to 17 March 2021), 430 tests returned a positive result, and 535,667 tests returned a negative result. Since LFD tests were introduced, 20,442 positive results and 5,228,418 negative results have been reported.

Figure 5: number of LFD and PCR tests conducted in care homes, England

This data can be found in the ‘table_8’ and ‘table_9’ tab of the ‘Tests conducted: 28 May 2020 to 17 March 2021 data tables’ on the weekly collection page.

About this data

Lateral flow device tests were first made available from 21 October 2020 in England. This data contains LFD tests reported through the existing National Testing Programme digital infrastructure and does not include LFD tests conducted where the tests were not registered via this route that is used to collect data for this report.

The following use cases for LFD tests are not currently reporting results digitally into Test and Trace systems, and therefore are excluded from this report:

• testing for the majority of NHS secondary care staff
• testing for some staff in private sector industries
• testing for some hauliers, these are published separately see haulier coronavirus testing

In these cases, test results should be reported directly into Public Health England. In future, all LFD tests will be reported via the existing National Testing Programme digital infrastructure and will be included.

A full explanation of the data sources and methods used to produce these statistics can be found in the NHS Test and Trace statistics methodology.

Data quality

Given the importance of this service and the commitment of NHS Test and Trace to be open and transparent with the public it serves, this data is being released at the earliest possible opportunity. However, this data should be treated with caution whilst the understanding of the data and its quality improves.

The requirement for care home staff to register negative LFD test results was suspended between 31 December 2020 and 15 January 2021 inclusive, following a change in guidance issued on 23 December 2020 to increase testing in care home staff. As a result, a proportion of LFD tests conducted on care home staff will not be included for these dates.

An LFD test produces a result on the device almost immediately, without it being automatically recorded, therefore some results might not be captured. For settings where self-reporting LFD testing procedures^{[footnote 4]} are in place, it is likely that the number of tests conducted are underreported. It is however their statutory duty to do so, and easier reporting tools are being rolled out to support these individuals to report their tests as quickly and efficiently as possible. It is possible that tests with a negative result are more likely to be affected, therefore it is not advisable to calculate a positivity rate with the data.

Positive test results are not published as a proportion of the total number of tests conducted. There are several reasons why it is not advisable to calculate a positivity rate with this data:

• the number of tests conducted is not deduplicated and refers to the number of tests taken and not the number of people tested. Because people can have more than one test, the number of tests conducted therefore cannot be compared with prevalence or case positivity rates

• rapid testing is primarily used for repeat testing of asymptomatic individuals and the frequency of testing varies across different settings, therefore positivity rates would not be directly comparable

• the potential underreporting of tests conducted by individuals self-reporting is more likely to affect negative test results than positives thus skewing any positivity rate calculation

More information on data limitations and how the figures in this publication can and can’t be used is outlined in the NHS Test and Trace statistics methodology.

Future developments

We continue to explore the feasibility of adding new breakdowns to the publication on rapid testing to support user needs. Over the coming months, we intend to make data available on the following:

• individuals tested in care homes (staff, residents, visitors)

• rapid testing for asymptomatic NHS staff

• rapid testing in public and private industries

• community testing programme

For feedback and any further questions, please contact statistics@dhsc.gov.uk.

1. Self-reported results from LFDs are where the individual carrying out the test on themselves is expected to report their own test and subsequent result. ↩

2. Counts of LFD tests conducted do not include tests which weren’t reported through the National Testing Program digital infrastructure. ↩

3. Absolute number of tests conducted in each region and does not take into consideration population of regions. ↩

4. Self-reporting LFDs are where the individual carrying out the test on themselves is expected to report their own test and subsequent result. ↩