The UK is to offer antibody testing to the general public this week for the first time.
Who will be able to get a test?
Anyone aged 18 or over in England, Wales, Scotland or Northern Ireland will be able to opt in to a programme when they get a PCR test.
They will be sent two finger-prick tests to complete at home and this will inform the UK Health Security Agency (UKHSA) of the antibody response to different coronavirus variants.
Up to 8,000 people will be enrolled in the programme, which is run by the UKHSA alongside NHS Test And Trace.
When should the tests be taken?
The first of the two tests should be taken as soon as possible after receiving a positive PCR test result, while the second should be taken 28 days later.
It is important that the first antibody test is taken as soon as possible so that the body hasn’t yet had the chance to generate a detectable antibody response to the infection.
The second test, taken 28 days later, will measure antibodies generated in response to the infection.
What is an antibody test?
The test checks for antibodies in your blood.
Your body makes antibodies when you get an infection and the antibodies help fight the infection.
If you have COVID-19 antibodies, then it’s likely you have had the virus before – even if you did not have obvious symptoms.
According to the NHS, it is not known if having antibodies can stop you getting the virus again.
What if I’ve been vaccinated?
According to the US Centers for Disease Control and Prevention, if you do an antibody test after your vaccine, you might test positive for antibodies on some – but not all – tests, depending on which type of antibody the test detects.
The UK government says that the antibody tests used in the programme from this week will detect your body’s response to the virus or vaccination, however it will not be able to tell if you currently have COVID-19.
It adds that you can still enrol in the programme and use the tests if you have had a COVID-19 vaccine.
When do I get my results?
The government’s coronavirus testing webpage says that you should have your result within three to seven days of taking the test and it will usually arrive by text or email.
You should read the message carefully to make sure you understand what your result means.
A positive result in this case is good news – the test detected COVID-19 antibodies, meaning you are likely to have some protection. However, it is still possible to spread the virus if you have it.
A negative result means the test did not detect COVID-19 antibodies.
Most people make antibodies within 28 days of being infected or vaccinated but it can take longer than that.
A void result means the test did not work – possibly because there was a problem with the test kit or the blood sample was not big enough. It is still important to record this result for the purposes of the research programme.
What if I think the result is wrong?
No at-home test is 100% accurate all of the time and we’re dealing with a new virus, so we’re still understanding how our bodies respond to it.
For example, we still don’t know for sure how long antibodies last.
If you have concerns about your result, call 119 (free from mobiles and landlines) between 7am and 11pm any day of the week. They can provide support in 200 languages as well as well as InterpreterNow – a free online British Sign Language interpreter.
Are there any privacy concerns?
You can read about the details that will be collected and processed here.
Do I still need to be careful around others if I have the virus but I have antibodies?
Yes. Regardless of your antibody test result, you must follow the same guidelines as everyone else to protect yourself and others from the virus. Remember, you might have antibodies, but the vulnerable person in your household might not.