One of the peculiar quirks of the Covid era is our newfound preoccupation with the ins and outs of testing.
Right at the beginning of the pandemic, when we were seeing the first trickle of cases on our hospital wards, all we knew about the SARS-CoV-2 testing was that it wasn’t very good.
As many as a third of infected cases were producing false negatives, which may have been, in part, due to the unfamiliarity we had with even using the swabs – how far should they go in? Nose or mouth first? What bottle does it go in?
Flash forward six months and everyone is now an expert, or so it seems. And our fractured testing system has only got more complicated, after Boots announced it would offer a new rapid test that can give you a Covid result in just 12-minutes. The catch? It’ll cost you £120.
Testing in the UK has been a contentious subject since the start of the pandemic, riddled with endless controversies, including the abject failure of the outsourced test and trace system.
The government offers four pillars of Covid testing: 1 & 2 are nose and throat swabs, which look for specific sequences of genetic material in the lab, detecting current infection, called RT-PCR. Pillar 1 is for hospital patients and Pillar 2 the outsourced community testing programme. Pillar 3 is antibody tests, looking for recent or past infection. Lastly, Pillar 4 is surveillance, and is a combination of the above.
But the Boots test, known as the LumiraDx, is a different type altogether, called an antigen test to detect current infection. So is this pricey, private test a good addition to the testing arsenal?
In short, no.
Firstly, all tests have limitations – producing both false negatives and false positive results. Even for the gold standard, false negatives still occur between one in three and one in 50 positive cases, meaning an infected person would be walking around thinking they are disease-free.
Notably the Lumira test is “comparable to” but not the same as the current swab testing, increasing the false negative rate further, especially at a delay from symptoms.
Worse, even if you are infected early on, you can still test negative and then positive again just a day later, as the amount of virus in your body changes rapidly, so the “peace of mind” this can give you is short-lived.
Regardless, for those that might be thinking of popping into Boots on the way to see Grandma, this may seem an attractive option – if you can afford it. And therein lies one of the biggest problems with this set-up, on two levels.
The first is cost. This kind of quick-access testing could enable a more normal life, but is currently only available to those with considerable disposable income at hand. It’s a markedly unjust arrangement, and is morally questionable. Testing is a vital public service – every Briton should have equal access to testing, regardless of income or circumstance.
The stakes are even higher for NHS workers who are still struggling to access the tests they need to continue working. It’s not right that healthcare professionals who are at a higher risk of contracting Covid are second in line to those with a spare £120 in their pockets.
“The right solution here, both in ethical terms and for public health, would be a ubiquitous, freely available testing system, with rapid turnaround.”
Already we have had iatrogenic outbreaks on vulnerable cancer wards, and as community prevalence continues to rise this is an ever increasing risk. NHS staff are also parents and carers, accessing rapid and reliable tests for their dependents means we can return clinical staff back to the wards again ASAP without extended self-isolation.
The contrast of an expensive, high-street rapid test available when staff themselves aren’t being routinely tested throws this disparity into sharp relief.
The second is the clinical interpretation – despite Boots advertising this as for those with no symptoms, the Lumira appears to be only licensed for those “with symptoms or at risk of infection”. The worry here is that such a test will be used by those who can afford it, not as clinically intended, to ignore the guidelines as they are currently, or take additional risks, which may spread the virus further.
The right solution here, both in ethical terms and for public health, would be a ubiquitous, freely available testing system, with rapid turnaround. While NHS Scotland has indeed ordered LumiraDx tests themselves, NHS England is only managing to turnaround 15% of tests in 24 hours, with waits up to a week for the results, which makes them next to meaningless.
Ultimately, Covid testing is in disarray. As cases rise, the percentage of contacts reached dwindles ever further, and despite the tier lockdowns, no significant reversal of the spread has occurred in any region.
While advances in testing are welcome, they need to be equitably introduced, and prioritised to where they can have the greatest impact in combatting the pandemic.
The risk here is that Boots’ new test is likely to do more harm than good, and further divide an already increasingly unequal society, at a time when we should be pulling closer together.
Dr Dominic Pimenta is an author and doctor.