Is it possible to get a false positive Covid-19 test result?
The accuracy of coronavirus tests has been called into question in recent months.
Superdrug became the first high-street retailer to offer a Covid-19 antibody test and numerous websites offer similar tests, including Lloyds Pharmacy. However, sales of its antibody finger prick tests were suspended in April following warnings from a health regulator about the reliability of such tests.
The body said that people who have so far used a finger prick antibody test “should not consider the results to be reliable and should not take any action on it”.
In June 2020, a health select committee questioned Baroness Dido Harding – the head of NHS Test and Trace – on why members of the public were not repeatedly being tested for coronavirus.
Former health secretary Jeremy Hunt, cited evidence compiled by the University of Bristol which found that Covid-19 swab tests produced false negative rates of between 2 per cent and 29 per cent.
However, the accuracy of testing depends on a range of factors including the type of test being used.
For example, 5,000 “Nudgebox” machines, supplied by a biotech called DnaNudge, will provide 5.8 million tests to hospitals, care homes and laboratories in coming months.
Nudgebox was only approved by the Medicines and Healthcare Products Regulatory Agency in April after trials showed that it achieved sensitivity (the rate of positive tests) of 98 per cent and specificity (rate of negative tests) of 100 per cent.
The machines, already in use in eight London hospitals, analyse the DNA in nose swabs and can process up to 15 tests on the spot each day, giving a result in up to 90 minutes.
What are the new Rapid tests, and how can I get one?
The two new tests announced by the Government earlier this month include DNA tests and swab tests. Some 5,000 “Nudgebox” machines, supplied by a biotech called DnaNudge, will provide 5.8 million tests in the coming months, the department said.
The machines, already in use in eight London hospitals, analyse the DNA in nose swabs and can process up to 15 tests on the spot each day, giving a result in up to 90 minutes. They can be operated outside a laboratory and do not require staff to undergo specialist training. More machines will be rolled out across NHS hospitals from September.
The second new test, known as the LamPORE test will be able to process swab and saliva samples to detect the presence of Covdi-19 in 60 to 90 minutes. The new test, developed by Oxford Nanopore which spun out of Oxford University, has the same sensitivity as the widely-used PCR swab test but can process swabs outside specialist laboratories.
A palm-sized machine will process up to 2,000 tests a day while the larger desktop machine will be able to analyse up to 15,000 tests.
These new tests are not available to purchase over the counter or online, but you may be tested using one through the Government’s Test and Trace scheme.
The testing kits may also be introduced to “non-traditional settings” such as schools or could be used in hospitals to provide regular testing of staff.