Factsheet: understanding the testing landscape for COVID-19

Testing, tracing, and isolating are a core part of the UK’s toolkit in the fight against COVID-19, and are likely to remain so until the majority of the UK population is vaccinated. Tests can identify whether someone currently has the disease, helping to pinpoint isolated cases and outbreaks. Tracing works by identifying the contacts of a confirmed case and asking them to self-isolate for 10 days if necessary.

Testing, tracing, and isolating are a core part of the UK’s toolkit in the fight against COVID-19, and are likely to remain so until – and even after – the majority of the UK population is vaccinated.

The testing landscape is fast-moving and complex to navigate. The CBI has created this factsheet to complement our guidance on NHS Test and Trace and private workplace testing, to help you understand the terms you might encounter when engaging with testing or third-party healthcare providers.

What’s the latest insight and information?

People can access tests through NHS Test and Trace and privately if they have symptoms. Increasingly people can also privately access tests if they are without symptoms either for the purposes of travelling or for peace of mind. Recently this type of asymptomatic testing has also been trialled by the government in various community and workplace settings, with view to aiding the economy to reopen when feasible.

There are several types of test with different pros and cons, from the gold-standard RT-PCR used by NHS Test and Trace to quick and cheap rapid antigen tests.

The government has announced that asymptomatic testing is being expanded to those that cannot work from home during the current national lockdown. Read the CBI’s response to the announcement. Looking ahead the government is working across departments to scale up workforce testing in the weeks to come, with the CBI engaging on this issue.

What types of tests are available to businesses?

There are a variety of different COVID-19 tests available, with trade-offs between accuracy, pace, cost, and usability – which may impact which scenarios or workplace settings they are most suitable for. These can often depend on whether tests are point-of-care or lab analysed:

• Lab analysed tests see samples collected and sent to labs – generally producing more accurate tests but with a longer waiting time
• Point-of-care tests are currently intended to be used outside a lab by a health professional or trained employee, with a quicker turnaround but potentially less accurate results.

Accuracy is measured against two factors:

• Sensitivity: The ‘true positive’ rate – i.e. how well a test detects positive results for people who actually have the disease. For employers, a test with a lower sensitivity rate is more likely to lead to staff having to self-isolate unnecessarily
• Specificity: The ‘true negative rate’ – how well a test detects negative results for people who don’t have the disease. For employers, a test with a lower specificity rate could risk infectious individuals continuing to enter the workplace. This risk can be mitigated with a higher frequency of testing.

Employers should note that no test will be completely accurate, and it will only give a result for that point in time at which a test is taken. Testing should therefore complement, not replace, other COVID-secure measures introduced by firms to stop the spread of the virus, as outlined in the CBI’s factsheet on returning to work safely.

The government advises that businesses discuss with their provider what tests are appropriate for their workplace dependent on use, case and need for accuracy and frequency. The most commonly deployed tests in use by government and some businesses, and which your firm might want to consider introducing, include:

Viral/diagnostic tests – to see if you’re currently infected

• RT-PCR: Regarded as the gold-standard in testing, RT-PCR tests are highly sensitive and specific. However, they are slightly more expensive and can have a longer turnaround time due to being lab analysed. They are performed using a nasal and throat swab and, in most cases, require a medical professional to administer. Most tests conducted by NHS Test and Trace use RT-PCR technology. In the UK these have an analytical sensitivity and specificity of greater than 95%
• Lateral flow device (LFD) antigen: With the ability to be performed in a laboratory or point of care setting, these swab or saliva tests are cheaper and quicker than RT-PCR tests, with results available in 60 minutes or less. Antigen tests tend to have high sensitivity (making positive results highly accurate) but can have lower specificity (meaning there is a margin of error for negative results). Lateral flow devices, a mechanism that allows test results to be more easily interpreted by eye, are used without the need for specialised equipment. Lateral flow devices are most commonly used in pregnancy tests. To date this style of test has been used in community testing including in high local tier areas such as Liverpool, care homes, universities and for HGV drivers crossing the border to France. At present, research and analysis from Public Health England and Oxford University show the accuracy of LFDs to be of 99.68% specificity, an overall sensitivity of 76.8% and a sensitivity of over 95% for those with high viral loads
• RT-LAMP: A test using a swab or saliva samples. Quicker and cheaper than RT-PCR, with results that can be read by eye. The OptiGene RT-LAMP test has been approved, with a sensitivity of 79% and specificity of 100%, rising in samples with a higher viral load
• LamPORE test: A novel, lab analysed test using LAMP technology combined with nanopore sequencing, again able to process both swab and saliva samples. Analysis from Oxford University has suggested the test has a sensitivity of 99.1% and a specificity of 99.6%.

Antibody/serology test – to see if you’ve been infected in the past

• Antibody: Test that detects whether someone has had COVID-19 using a finger prick or blood test. An antibody test does not tell someone whether they currently have the virus, if they’re immune, or whether they can spread it to others.

Frequently Asked Questions

How do tests and testing providers get approved?

The UK’s approvals process requires COVID-19 tests and providers to meet a number of criteria. The Medicines and Healthcare Regulatory Agency (MHRA) regulates testing kits. Testing kits approved for use must have a valid CE mark to show that the manufacturer has met the minimum safety and performance requirements for the product.

The MHRA has also developed Target Product Profiles (TPPs), setting out how different tests work, the standards they should meet (for example the level of sensitivity and specificity), and their target scope – for example, target use, user, and use setting. PCR tests should be processed by UKAS-accredited labs. Adverse experiences with medical devices like testing kits can be reported to the MHRA using the Coronavirus Yellow Card reporting site.

The government has also set out the minimum standards testing providers must meet in its guidance for self-declaring as a private sector COVID-19 testing provider. A list of providers who have declared they meet these standards (with government performing due diligence tests) can be found here.

What are the routes available for employees to get a test?

The NHS Test & Trace programme continues to provide testing for anyone with symptoms of the virus as well as tracing their contacts. Read the government’s workplace guidance on Test & Trace. The CBI has also produced a factsheet on NHS Test & Trace and the app.

Some employers are undertaking private workplace testing, working closely with local public health authorities to share learnings. The government has produced practical guidance for employers who want to offer workplace testing for asymptomatic employees in addition to the list of approved providers mentioned above.

Businesses are now able to register their interest to receive in bulk lateral flow tests free of charge to distribute to staff who are unable to work from home during the current lockdown. The government will provide the testing kits and staff communication tools whilst businesses will be required to set up a test site and train staff to operate it. 

Further resources

• Read the CBI’s guidance around the impact of testing on employers and employees, including our factsheets on NHS Test & Trace and on private workplace testing for COVID-19
• Watch the CBI’s webinar with Baroness Dido Harding, Executive Chair of NHS Test and Trace, and Rebecca Weston, COO of Sellafield, to gain insight into how one firm is approaching workplace testing
• Watch the CBI’s webinar with Ben Osborn, MD and UK Country Manager of Pfizer, and Professor Devi Sridhar, Chair of Global Public Health at the University of Edinburgh, which provides insight into COVID-19 vaccination and the continued importance and potential of mass testing
• Read the government’s practical guidance for employers who want to offer workplace testing for asymptomatic employees and the government’s list of approved private testing providers.