Article: UK's testing policy makes their Covid19 numbers meaningless

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May 1st was the deadline that UK Health Secretary Matt Hancock set for the NHS to be testing 100,000 people every 24 hours.

Seeing as the 100,000 was just an arbitrary number, set up for PR purposes to make the government look dynamic and pro-active, whether or not they actually hit this target is moot.

Nevertheless, steadfast in their duty to discuss only that which does not matter, the mainstream media are locked in a fierce debate over the statistics. One which not only buries the lead but burns off its fingerprints and pulls out its teeth first.

Some people claim the 122,000 tests is MORE than his promised 100,000 daily tests. Others point out that since those 122,000 tests were only on 73,000 people he actually missed the target.

Both are missing the point: The testing policy as a whole is producing potentially meaningless data.

For example UK apparently just admitted to testing 50,000 people twice in one day.

This is potentially significant because it's evidence to support the numerous anecdotal reports of patients being repeat-tested for Covid19 without ever getting a positive result (and sometimes without displaying any symptoms). But it's also itself a symptom. A natural side-effect of some very poor NHS advice.

The latest version NHS guidance for managing Covid19 says this about PCR tests:

Beware false-negative upper airway sample if clinical picture is typical

Clinicians are being advised that if they have a patient with "typical" symptoms of Covid19, that any negative test could be a "false negative" and potentially disregarded.

This might explain why doctors would want to redo some tests, but selectively ignoring negative results is a highly irresponsible policy, especially if you base those decisions on a "typical clinical picture" for a disease with a very common pattern of symptoms.

The "typical" clinical presentation of Covid19 is a fever, cough and shortness of breath. This is far too vague to be used to clinically diagnose anything, and could obviously lead to thousands of patients with flu, colds or other minor respiratory infections being listed as Covid19 cases. Either because they were tested for Covid19 repeatedly until they got a positive result, or because they had their negative result dismissed as a "false negative" and were clinically diagnosed.

Clearly this approach could artificially inflate the number of Covid19 cases. This would be true even if your test was a reliable diagnostic tool. The PCR test they use to "diagnose" Coronavirus infection is not reliable.

In fact, the evidence calling these tests into question is pretty extensive (you can read Kevin Ryan's detailed write-up here):

An early study, done in China, found two PCR tests from the same patient at the same time could return different results. Another Chinese study (since retracted for unexplained reasons) found the PCR tests returned huge numbers of false positives. In the UK a batch of tests was discovered to be contaminated with Coronavirus. In the US, the tests were found to react to the negative control sample when they should not (potentially leading to false positives). In Germany, an 84-year-old man tested positive, leading to his entire nursing home being quarantined. It was later found he actually only had a common cold. During the SARS outbreak of 2003, PCR tests in Canada were found to respond to all coronaviruses, not just SARS-Cov. In a report dismissing the idea of "re-infection", South Korea's CDC claimed PCR tests produce false positives because they cannot tell the difference between a live virus and a dead one, adding that patients could continue to test positive for months after their immune system has killed the virus.

PCR tests cannot be relied upon to produce good data. When you combine their use with guidelines instructing doctors to disregard negative results, rely on clinical diagnosis for an incredibly common symptomatic presentation, and re-test thousands of people every day, you have created a perfect storm for misdiagnosis.

Whether through contrivance, panic or incompetence, Matt Hancock's much-hyped mass testing plan is potentially little more than a waste of time and resources.