The government has presented plans for the British to carry out antibody tests against coronaviruses at home, with finger prick kits that will be available on Amazon and Boots.
But what are these tests – and do they work?
What is an antibody test?
An antibody test can detect whether a person has ever had a coronavirus and has since recovered. The test, performed by a device that pricks your finger for blood, works by testing your blood for anti-coronavirus antibodies to see if they have already beaten the virus and acquired some immunity against it. He can do it in about 15 minutes.
The coronavirus swab test that the government is currently using can only tell if a person has the virus, not if they had it and recovered. These swab tests also take much longer to get a result.
The antibody test is also called a “serological test”.
The government hoped to launch millions of antibody tests in the coming weeks, but Chinese supplies have so far failed the sensitivity and specificity tests.
Ministers will attempt to recover taxpayer dollars spent on fingerprint testing after a Oxford University trial found that they returned inaccurate results.
The failure is a major setback as it was hoped that antibody tests would show who had already developed immunity, thus providing a faster route out of the lockout.
Last week, however, Professor Karol Sikora, a private oncologist and Dean of Medicine at the University of Buckingham, validated a test kit using samples from the staff of his clinics, which were then verified. by a private laboratory.
It has been found that around 6% of staff have the virus, but more importantly, those under 40 who tested positive returned negative, suggesting that the test may not be useful to the general population.
What is an antigen test?
An antigen test detects the presence (or absence) of an antigen, not an antibody. An antigen is a structure within a virus that triggers the immune system’s response to fight infection. It can be detected in the blood before antibodies are made.
An antigen test is effective because it can take a few days for the immune system to build enough antibodies to be detected in a test, however, antigens can be detected almost immediately after infection. So, in theory, the test can tell a lot sooner if someone has the virus.
Antigen tests are used to diagnose HIV, malaria and the flu.