A new 12-minute coronavirus test soon to be on offer at Boots could prove problematic, a medical expert has warned.
Paul Hunter, a professor in medicine at the University of East Anglia, said the benefits of the £120 nasal swab would be “very limited”, in part because a negative test tells you nothing about whether you are going to be positive a day or two later.
The pharmacy chain said the technology, made by life sciences company LumiraDx, will be rolled out in selected stores over the next few weeks, and that the service has a 97% accuracy rate.
But Professor Hunter told BBC Radio 4’s Today programme: “The big problem with this sort of testing, apart from the price... is that it seems to be targeted at people who don't yet have symptoms so the chances of them being positive is actually very low.”
Watch: Coronavirus: Boots announces 12-minute COVID tests
He noted that if many of the 3% of tests that give incorrect results give false positives, “most of the positives from the tests would actually be false positives, because asymptomatic people probably have less than 1% chance of being positive anyway.
“A test like that would throw more false positives than negatives if the false positive rate is around 2-3%.
“The other thing is that a negative test today tells you nothing really about whether you are going to be positive a day or two later.”
He added that many asymptomatic people who test positive are probably recovering from the virus earlier and the virus may be non-infectious, “so a lot of the positives probably aren't going to be important in terms of posing a risk to infection”.
There would be some contexts and settings in which the tests could prove useful, he said, such as at job interviews or TV appearances “where they wanted to see if that time you were likely to be negative”, but “it would probably be limited”.
Boots has also launched a 48-hour testing service that is currently available in 10 stores in London, Birmingham, Manchester, Edinburgh and Glasgow, and plans to extend the programme to more than 50 outlets across the nation.
The service is available as a private pre-flight test for customers travelling abroad, or as a solution for those who would prefer peace of mind before seeing friends and family.
Seb James, managing director of Boots UK and ROI, said the programme was being implemented as a way to help ease the pressure on the nation’s health services.
“Boots has supported the government’s COVID-19 testing programme from the very start and offering this new in-store service is the next step in our efforts to fight against the pandemic,” he said.
“We hope that by offering this testing option in local community stores, Boots can help ease pressure on the NHS and the government by providing additional access to testing and crucial reassurances for people across the UK.”
Customers who are not displaying any COVID-19 symptoms can book an in-store test through the company’s website boots.com.
In-store testing at Boots comes alongside the rollout of COVID-19 testing in some UK airports.
As of last week, passengers flying from Heathrow to Hong Kong will have the option of paying for a rapid test before checking in, costing £80. The results will be available within the hour.
Some destinations require proof of a negative result on arrival, including Hong Kong and Italy.
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