Information on lateral flow testing for people who have to leave home for work.
What is rapid testing?
Rapid testing using lateral flow devices (LFDs) involves taking and processing tests for COVID-19 directly at the point of care (e.g. workplace, care home). Samples are taken using nose and throat swabs and results are provided in around 30 minutes. Lateral flow tests look for parts of the surface of the virus (antigen) that are present during active COVID infection.
Currently, LFDs are targeted at people who do not have coronavirus symptoms (asymptomatic). Anyone with symptoms of COVID-19 should isolate and access a PCR test. Find more information about accessing PCR tests in North Yorkshire.
Rapid testing is an additional measure that can be used to try and reduce the risk of infection. The benefit of lateral flow tests is that they can provides results quickly, without the need for delay in sending swabs to a laboratory. However, as with many tests decreasing turnaround time means that there is also a decrease in accuracy.
A negative lateral flow test result does not mean that an individual definitely does not have COVID-19 and that there is therefore no risk. Individuals with a negative lateral flow test result should continue to practice social distancing, hand and respiratory hygiene, and all other existing infection prevention measures to try and decrease the spread of disease.
The purpose of rapid testing with LFDs is to identify additional cases in asymptomatic people who would otherwise not have been detected, to prevent further spread of infection. Lateral flow tests are not currently approved for serial testing of close contacts to bypass the need to self-isolate (‘test to enable’).
North Yorkshire rapid testing programme
North Yorkshire County Council have received approval from the Department of Health and Social Care to introduce a local rapid testing programme focusing on critical workforces across the County. We will be working with employers to set up lateral flow testing through individual workplaces, similar to the model currently employed in care homes and schools. The programme will be rolled out in a phased manner, starting with critical category 1 and 2 responders.
In addition to providing the lateral flow tests, We will also provide training and support for staff as the process is rolled out. Working directly with employers helps to ensure that staff testing is carried out regularly and results are acted upon immediately, which will give the most benefit from lateral flow devices.
More information on the local rapid testing programme and the organisations eligible to apply will be made available on this website once the programme is operational.
National workplace rapid testing programme
Businesses with more than 50 employees are now eligible to apply to join the national workplace rapid testing programme.
You can register to order tests if:
- your business is registered in England
- you employ 50 people or more
- your employees cannot work from home
For more information please contact email@example.com.
Other rapid testing programmes
Rapid testing using LFDs is being offered directly to NHS staff, adult care homes and educational settings (primary, secondary and specialist) across the County.
For more information on these national programmes please visit:
How accurate are lateral flow tests?
The preliminary evaluation report found Innova LFDs are very good at correctly identifying people who do not have coronavirus – 99.68% of people in the evaluation who did not have COVID-19 were correctly given a negative test result. This means that 0.32% of people who did not have COVID-19 were incorrectly told that they did have coronavirus (false positives).
However, LFDs are not as good at correctly identifying people who do have coronavirus (sensitivity). The Innova evaluation found that 76.8% of people who would have been picked up as positive cases on PCR testing received a positive result with a lateral flow test. However, this varied depending on who was taking and processing the tests: when done by trained laboratory staff 79.2% of positive cases were correctly identified, when done by trained healthcare workers 73% of positive cases were correctly identified, and when done by self-trained members of the public 57.5% of positive cases were correctly identified. This means that there is a significant proportion of people who would have tested positive with a PCR test who received a negative lateral flow test result (false negative rate between 20.5% and 42.5%).
Lateral flow tests perform better at picking up cases with a high viral load (i.e. more virus is present), who are thought to potentially be the more infectious cases. However, even some of these will be missed.
This is why a negative lateral flow test result does not mean that an individual definitely does not have COVID-19 and that there is therefore no risk. Individuals with a negative lateral flow test result should continue to practice social distancing, hand and respiratory hygiene, and all other existing infection prevention measures to try and decrease the spread of disease.
What are the risks and benefits of lateral flow testing?
- Around one third of COVID cases are in people who do not have COVID symptoms (asymptomatic). Undertaking regular testing of asymptomatic people should lead to the detection of cases that otherwise would not have been picked up. These people can then be isolated and any close contacts identified, which can help break chains of COVID transmission.
- LFDs provide rapid results (processing time 30 minutes), without the need to send tests to a laboratory. It is possible to respond to positive results quickly by isolating individuals and decreasing the risk of further spread.
- LFDs will not pick up all COVID cases, although they are more likely to pick up cases with high viral loads (who are potentially more infectious).
- There is a risk that people who have a negative lateral flow result will assume they do not have COVID and will therefore behave as though they cannot spread disease (i.e. no longer feel it is necessary to socially distance, wear a face covering, regularly wash their hands etc.)
- LFDs are an additional measure of protection but it is very important that they should be used in conjunction with the above measures, not replace them. Complacency could lead to an unintentional increase in the spread of disease.
Who should use lateral flow tests, and how often?
Currently, LFDs are targeted at people who do not have coronavirus symptoms (asymptomatic). Anyone with symptoms of COVID-19 should isolate and access a PCR test (find more information about accessing PCR tests in North Yorkshire).
As part of the roll out of community testing programmes, the national advice during lockdown is to focus lateral flow testing on individuals who are permitted to leave home for work (including essential voluntary work) and who are unable to access asymptomatic testing through other routes. Priority is for critical workers working to support communities and the pandemic response, particularly those whose jobs put them at a higher risk of infection and transmission.
Many workplaces and other environments will be able to operate in a COVID secure manner, where there is very low risk of COVID transmission. However, some people will be required to work in places and situations where there is an increased risk of transmission (e.g. if social distancing is not possible due to the nature of the work undertaken, or they are interacting closely with individuals who are COVID positive or have unknown COVID status). These groups are at a higher risk of exposure and so are more likely to benefit from lateral flow testing.
Antigen testing (including lateral flow tests and PCR tests) only tells you if virus is detectable in the body at the time that the test was done. It is possible that an individual could become infectious shortly after taking the test. The interval between tests needs to be short enough to increase the chance of catching someone with COVID when the virus is detectable, but not so short that the testing programme becomes a significant burden.
NHS and care home staff are currently advised to test their staff twice a week. However, shift/working patterns of staff will need to be taken into account, so a different interval may be more practical (e.g. once every 8 days for people working 4 days on/4 days off, on the day they start their shift).
What happens if I get a positive lateral flow test result?
A positive result means it is likely you had coronavirus when the test was done.
You and anyone you live with must self-isolate immediately and keep self-isolating until you're no longer infectious. The self-isolation period includes the day you had the test and the next 10 full days.
You may be contacted by the NHS or your local council and asked for information to help alert your close contacts.
Support if you need to isolate
If you are required to self-isolate following a positive test result and need help with shopping or other essentials, please let family, friends or neighbours know how they can help you. If you don’t have anyone else to call on, you can contact us and we will direct you to help in your area.
If you do not have access to the internet, our contact centre is open seven days a week between 8am and 5.30pm so please call 01609 780780.
Exception: If you have a positive LFD result taken through an NHS, care home or primary education setting then you will need to isolate and complete a confirmatory PCR test. If the PCR test is positive you continue to follow the guidance above. If the PCR test is negative there is no need to continue isolation.