In the last two years, regular coronavirus testing - with PCR or lateral flow tests - has become a part of daily life for millions. Many believe that regular testing - especially if they are going to be in crowded environments or around someone vulnerable - is part of being a responsible citizen.
But are they right?
There are several question marks over the efficacy, reliability, and safety of tests, which are important to be aware of when making the decision when and whether to test.
The widely-regarded "gold standard" test for confirming a case of COVID-19, the PCR test, is not without some quite significant controversy, owing to its history of creating "fake epidemics" with an overabundance of false positives.
The PCR test is very sensitive, and can have trouble distinguishing serious respiratory diseases, like whooping cough, from less serious ones, like influenza, and even the common cold.
The New York Times reported a cautionary tale from 2007, when a hospital in the USA falsely declared a pertussis (whooping cough) epidemic, on the basis of PCR testing. The PCR returned many positive results for pertussis, meaning parts of the hospital were shut down, staff furloughed, and even beds in the ICU taken out of commission.
However, when the test results were taken to the lab to verify, and using the definitive test of growing the bacterium, Bordetella pertussis, in the laboratory, it was found all the positive results were false. Not one of the "positive cases" actually had whooping cough at all, but rather, they were afflicted with ordinary respiratory illnesses like the common cold.
Reflecting on the situation, Dr. Cathy A. Petti, an infectious disease specialist at the University of Utah, said the story had one clear lesson:
"The big message is that every lab is vulnerable to having false positives," Dr. Petti said. "No single test result is absolute and that is even more important with a test result based on PCR."
This echoes concerns voiced by the PCR test's inventor, Nobel Prize-winning scientist, Kary B. Mullis, who warned that, due to his test's very sensitive nature, "anybody can test positive for anything with the PCR. It doesn't tell you that you're sick".
PCR test technology works by amplifying results many times, and the number of positive results it returns for any given condition, depends on how many amplifying cycles are carried out when the results are analysed. A high number of cycles will result in a lot of positive results; a low number will result in a lower number. As a result of this, PCR tests have been labelled "unfit for purpose" where it comes to diagnosing infectious illness, with a positive result described as "scientifically meaningless" by some experts.
It's important to remember, as qualified by the test's inventor, that these tests were never designed to detect infectious illness, and that history dictates they do not do this reliably. A lot of the UK's pandemic response was based on the number of "positive cases", but as we have seen, these are not necessarily an indication that someone is seriously ill (or even ill at all).
Therefore, mass testing regimes can create false anxiety in individuals (who may test positive when in reality they have nothing more than a cold) and also put political pressure on governments to take drastic action to reduce "positive cases", when actually, no such action is required as many or most positive results may be false.
This is also so for the lateral flow tests, which many experts have warned against. The Guardian newspaper issued a report in 2021 warning of the dangers and inadequacies of the lateral flow test. According to the Guardian, lateral flow devices are "inaccurate and may cause more harm than good". The newspaper quotes Professor J. Deeks of Birmingham University and the Royal Statistical Society, and colleagues, who have stated in the British Medical Journal:
"The UK government is widening the rollout of the Innova lateral flow test without supporting evidence, and we understand that this may soon extend to further home use. This may cause serious harm. We call on the government urgently to change course.”
Many other experts harbour deep reservations about these tests, with Clinical Professor of Public Health, Allyson Pollock of Newcastle University, stating in the New Scientist that mass screening using lateral flow tests should not have been widely introduced before being tested for accuracy in the community. Pollock states: “[Lateral flow tests] have not been evaluated outside of a laboratory setting.”
Further than the tests' questionable efficacy, is the issue of safety. Inserting a swab far up the nasal cavity is an unorthodox method by which to test for a virus (which is usually done via blood test) and does not come without its risks. This invasive procedure can - especially when roughly or carelessly administered, which many report it often is, even in healthcare settings - penetrate the delicate membranes at the top of the nasal cavity, and cause brain fluid to leak.
Reports have also found that nasal swabs can be contaminated due to poor quality controls.
Of very troubling concern is that some companies have been found to be using PCR tests to harvest and sell human DNA, without either the knowledge nor consent of the patients.
It is important to carefully study and evaluate all of this information, before deciding when and whether to submit to PCR or lateral flow testing regimes.
As medical procedures that carry risks, these interventions should be regulated by the same laws on informed consent and ethical medicine as governs the rest of medicine in the UK. However, we are aware they are often not, and that many hospitals are known to engage in deeply unethical, coercive, and potentially illegal tactics, designed to force patients to undergo testing - even withholding urgent treatments and surgeries if patients decline.
We recommend getting legal advice should you find yourself in this situation. Robust medical ethics and human rights laws exist to protect your right to choose freely where it comes to your medical choices, and no individual should ever be coerced into any medical treatment or procedure that they do not want.
As with all things, free, uncoerced, and fully informed consent matters.