Anyone in the UK who has symptoms can apply online via the government website for a free coronavirus PCR swab test, which tells you whether you currently have COVID-19.
In addition, an increasing number of providers are selling private COVID-19 tests to the public, including high street pharmacy chains Boots, Superdrug and Lloyd’s pharmacy.
But these tests, which can cost anything from £40 to several hundred pounds, all offer slightly different things – and there are important caveats about what they can tell you, and who should use them.
We explain what you need to know if you want to get tested, including the difference between the types of coronavirus test, what’s available and what’s legitimate, as well as the limitations of current tests.
Coronavirus testing explained
Get the lowdown on the different types of tests, how the testing process works and understanding your results:
- Getting tested for coronavirus
- How does testing and tracing work?
- Understanding your COVID-19 PCR test results
- What’s happening with antibody testing?
- Do antibodies mean you’re immune?
- Can you buy an antibody test?
If you think you have COVID-19
Diagnostic swab test
The PCR swab test, taken from inside the nose and/or mouth, is the main one used by the NHS testing service and indicates whether a person is currently infected with the virus.
- This type of test takes longer to process as the samples need to be analysed in a lab.
- Currently, anyone with symptoms can get a coronavirus test as part of the UK testing and tracing programs.
- You can request the swab test online, and it can be done at a drive-through testing centre, at a mobile testing unit, or via a home-test kit.
The government website urges people to request a test as soon as they develop symptoms, and says testing must be done within the first five days of having symptoms.
If your test needs to be posted, you also need to allow time for it to arrive within that time.
The test involves swabbing the inside of your nose and the back of your throat, using a long cotton bud. You have to do it yourself and it can be unpleasant as the swab needs to go quite deep.
Testing in hospital is available for patients and some NHS workers, and a new rapid results antigen test has been introduced in these settings.
Private COVID-19 test services
An increasing number of private clinics – and now high street pharmacies – are marketing coronavirus swab testing services, either via a home test kit, clinician home visit, or clinic appointment (though some won’t see you if you have symptoms).
These tests are expensive: they are about £110-160 for a home or in-store test kit and up to £350 for a home visit. Estimates for results turnaround are between 24-72 hours.
What do the big chains offer?
To check if you currently have COVID-19:
- Boots: PCR swab test, £120 (in-store, currently available, similar to NHS one, processed in a lab, musn’t have symptoms, can be used as proof for travel if required)
- Lloyds: PCR swab test, £119 (delivered to you/posted, currently available, similar to NHS one, processed in a lab, not recommended as proof for travel)
To check if you previously had COVID-19:
- Superdrug: Antibody fingerprick test, £69 (delivered to you/posted, processed in a lab)
However, we don’t think anybody should have to pay for a pricey private test, and there are limitations around what the Boots and Superdrug offerings, in particular, can tell you.
Rapid coronavirus tests
As the name suggests, these tests – also commonly called lateral flow tests – have a quicker turnaround time than PCR tests, but there has been some debate about their ability to pick up asymptomatic infections.
They’re also done using a throat or nasal swab, with results available in around 30 minutes.
Mass testing of asymptomatic people is being rolled out across local authorities in England, particularly targeting people who are unable to work from home during the national lockdown.
This type of test is already being administered to many NHS workers at regular intervals.
Lateral flow test kits are also available through some private providers, but mostly they’re wholesale bundles intended for businesses.
Some scientists say that these tests have an important role to play in population screening, while others are concerned that false negatives could contribute to a false sense of security.
How does testing and tracing work?
The testing and tracing systems operate under slightly different guises across the UK. These are:
- England: NHS Test and Trace
- Scotland: Test and Protect
- Northern Ireland and Wales: Test, Trace, Protect
The basic steps for the testing and tracing systems operating across the UK are:
- Isolate: as soon as you have symptoms and for at least 10 days, while anyone you live with must isolate for 14 days from the onset of your symptoms
- Test: request a test as soon as possible
- Result: a positive result means you continue to isolate for the time set out above, if it’s negative you and anyone you live with can stop isolating
Share contacts: if you get a positive result, you will be contacted with instructions of how to share details of people with whom you have had close, recent contact and places you have visited.
How to tell if an NHS Test and Trace message is a scam – be alert for scammers taking advantage of the crisis
Understanding your COVID-19 swab test results
NHS advice says you do not need to isolate if you receive a negative result, as long as everyone in you household or support bubble with symptoms also tests negative, and if you haven’t been told to isolate by NHS Test and Trace.
Some doctors have raised concerns about the false negative rate for coronavirus testing, where your test is negative but you do actually have the virus, leading to possible false reassurance.
It is not known what the rate of false negatives is (a report in the British Medical Journal estimated it is between 2% and 29%), but a negative result from a swab test is conveyed to patients in very definitive terms – ‘you did not have the virus when the test was done’ – without any information about what might affect the result or its accuracy.
Government advice does tell people to continue isolating if you’re feeling unwell, even with a negative test result, so if you’re unsure, it’s best to stay at home.
If you’ve had a negative results from a rapid lateral flow coronavirus test and don’t have any symptoms, take the result with a grain of salt as evidence shows that these are prone to false negatives in asymptomatic cases.
There are also worries about the lack of information about an inconclusive test result, with patients simply being told their test is unclear and to apply for another one, but no information as to why this might be or how to avoid invalidating the test on another try.
If you receive an unclear result and you have symptoms, you must self-isolate for 10 days from the onset of symptoms, but if you don’t, you don’t have to self-isolate.
If you test positive, you must self-isolate for 10 days from when your symptoms started, or 10 days from getting your result if you are asymptomatic.
Anyone in your household or support bubble must also self-isolate for 10 days either from when your symptoms started or from when you got your result if you’re asymptomatic.
In England and Wales, you should be contacted by NHS Test and Trace after testing positive. In Northern Ireland, you will be contacted by the PHA Contact Tracing service, and in Scotland, you’ll be contacted by the National Contract Tracing Service.
If you’ve had a positive result from a lateral flow – or rapid – coronavirus test, you need to take a PCR test to confirm the result.
What about antibody tests?
Antibody tests are meant to show whether a person has already been infected with coronavirus. They work by detecting the presence of the antibodies our bodies produce to kill the virus.
Expanding accurate antibody testing would help experts understand how far the virus has spread, and how many people might have had it asymptomatically, or with mild symptoms.
How accurate are antibody tests?
Antibody tests are measured on specificity – which measures the proportion of ‘true’ negatives – and sensitivity, which measures the proportion of ‘true’ positives,
Jon Deeks, Professor of biostatistics at the University of Birmingham, says that while a positive result is fairly definitive, a negative result is less certain.
Professor Deeks explains that antibodies might not present as strongly in people with mild or no symptoms and studies so far have mostly been done on patients with severe cases – so this could skew the data for how accurate the tests are.
Still plenty of unknowns around COVID-19 immunity
It is hoped that once someone has had COVID-19, they are immune to the disease, but crucially, this is still uncertain.
The presence of antibodies in your blood can tell you you’ve been exposed to the virus, and therefore can also offer some information about how you reacted to it, but at the moment that’s about it.
The World Health Organisation (WHO) says: ‘We expect that most people who are infected with COVID-19 will develop an antibody response that will provide some level of protection. What we don’t know yet is the level of protection or how long it will last.’
It warned against making assumptions about a person’s immunity to coronavirus based on antibody testing. A positive result can’t yet be interpreted as a stamp of immunity, and there have been some suspected incidences of reinfection.
Any level of immunity can only be assumed in the short term because we just don’t have long-term data yet on how this virus behaves.
The Advertising Standards Authority (ASA) has banned some advertising from private clinics including the London Vaccination Clinic, Solihull Health Check Clinic and the Corona Test Centre London for claiming that a positive antibody test would show that people were immune to the disease.
Antibodies or T-cells?
Antibodies are also not the only way to gauge immunity from a disease. T-cells (a type of white blood cell) also play a role in the body’s immune response by mobilising the body’s defence mechanisms and destroying infected cells.
Researchers have discovered a T-cell response to coronavirus in people who didn’t have antibodies, but more research needs to be done in this area.
Can you get an antibody test?
Antibody tests, which identify if you’ve previously been infected with COVID-19, are available to buy from a range of private providers – most commonly they require a blood sample which is taken by a healthcare professional.
Antibody tests where you take your own blood sample with a home finger-prick test and send it to a lab for analysis were banned for a period of time, while the sampling process was being investigated by the Medicines and Healthcare Products Regulatory Agency (MHRA) to see whether it’s viable.
Superdrug has now relaunched its home fingerprick antibody test, which it says it compliant with the evolving MHRA guidance. The test is available through Superdrug’s online doctor service and costs £69.
The MHRA warns that ‘anyone using a sample collection kit to test for COVID-19 must read the instruction leaflet carefully. It is very important that you have a clear understanding of the process because if the sample is not collected properly, the result may not be accurate.’
Other private health companies such as Qured, Medichecks, DocTap and Forth are offering to send a healthcare worker to your house to administer the test, or selling antibody tests along with an in-person doctor’s appointment. This generally costs about £85-£130 per test.
We don’t think it’s worth spending money on an at-home coronavirus antibody test currently, as there’s a risk that they could give a false sense of security, and they can’t tell you much right now on an individual level.
Self-test coronavirus kits – where you take the test and read the results yourself at home – are not approved for sale in the UK and any company selling these is doing so illegally.
It’s important to note that you should continue to follow government advice around social distancing regardless of an antibody test result.
Story last updated: 5 November 2020 This story was originally published in March 2020 but has been regularly updated to reflect new information and rules around testing.