Boris Johnson has placed his faith in millions of cheap, reliable tests that provide results in minutes as a route out of future lockdowns caused by a resurgence of coronavirus.
Speaking a few hours before Tuesday’s announcement that Liverpool would be the first city in the UK to conduct population-wide testing for Covid-19, the prime minister declared that the quick turnround tests would “enable us to defeat this virus by the spring”.
As England prepares to enter its second national lockdown on Thursday, the government’s Operation Moonshot plan to deliver a mass population testing programme is back under the spotlight.
According to documents reviewed by the Financial Times, the Department of Health has awarded contracts worth at least £1bn to companies providing rapid testing. Many of the technologies relating to these contracts will feed into the Liverpool trial, in which everyone living or working in the city will be eligible for a test from Friday.
The strategy will hinge on new lateral flow tests, which give results in 20 minutes and can be performed on either a throat or a saliva sample, as well as conventional swab tests and loop-mediated isothermal amplification (Lamp) technology.
The pilot is expected to last about two weeks, with tests being deployed by the army, and could allow teachers, pupils and hospital staff to be tested weekly.
But scientists have raised concerns over the accuracy of some of the lateral flow tests being used, which are prone to missing cases of active infection. Meanwhile, delays in assessing technologies produced in the UK have led to frustration over government contracts being awarded to overseas companies.
Contracts
The government has so far signed at least 10 contracts with companies based in the UK, US and China, totalling more than £1bn, for rapid testing technology and logistics, according to publicly available contracts on the EU public procurement site, Ted, and information shared with the non-profit legal firm the Good Law Project.
The FT shared its calculations with the Department of Health, which declined to comment on the contracts, citing commercial sensitivity.
Despite a drive to turbocharge the UK diagnostics industry, the contracts show that the Department of Health spent £138m on millions of lateral flow tests produced by US company Innova, whose tests will be used in the Liverpool pilot.
It has spent more than £80m on two tests made by US companies Abbott and LumiraDX, which is also being offered by the pharmaceuticals retailer Boots, according to the documents. One person close to the procurement process said the government had also spent an unspecified sum on lateral flow tests produced by the Chinese company Zhejiang Orient Gene and the Korean medtech company SD Biosensor.
Another contract published last week shows that the government spent more than £1.35m to fly lateral flow tests from China to the UK, although it did not disclose further details.
“We’ve yet to find a UK-based lateral flow test that’s good enough,” according to a person directly involved in the validation process
The Innova tests, expected to play a main role in the Liverpool trial, were found to have 100 per cent specificity, avoiding false positives, and 96 per cent sensitivity, avoiding false negatives, in clinical trials.
However, the company’s instructions state that the tests can pick up infections from people “who are suspected of Covid-19 by their healthcare provider within the first five days of the onset of symptoms” and that they are designed for use by trained healthcare and laboratory staff.
“The Innova test is not approved for community use,” said Jon Deeks, professor of biostatistics at Birmingham university. “This is dangerous and not how science should proceed.”
One person close to the validation process said that some field studies of the tests in community settings, such as universities, had produced poorer results than others, indicating the need for robust training.
The different testing technologies
The government has mostly focused its investment on four testing technologies.
While the gold-standard reverse transcription polymerase chain reaction (PCR) tests are highly accurate, they are time consuming to process and require lab equipment and clinical expertise to analyse. They allow scientists to take a sample containing a very small amount of virus RNA, convert it to DNA, and multiply it so it can be detected.
Limited lab capacity and problems with the supply of reagents have meant that turnround times have remained stubbornly high for RT-PCR testing, with fewer than one in four results returned within 24 hours, contrary to what Mr Johnson promised in June.
To tackle the problem, a contract published in September shows that the government spent £6.4m on two state-of-the-art “End Point PCR” machines that can each process up to 150,000 samples per day. They were trialled at a government laboratory in Milton Keynes last month, according to the contract.
Lamp tests have been heralded by some as a more efficient alternative to traditional RT-PCR. Though they are generally much faster than conventional swab tests, for the most part Lamp technology still requires laboratory processing, which takes time and resources.
The government has signed contracts worth more than £430m with two UK companies, Optigene and Oxford Nanopore, for the supply of Covid-19 Lamp tests.
Infected individuals have Covid-19 in their saliva. Tests using saliva samples have been found to detect as much of the virus as does a throat swab. Some companies, such as Chronomics, have developed PCR tests that work on saliva samples.
Tests that give results at the same point they are administered, also known as point of care tests, are considered the government’s best bet for ramping up testing. Some use the lateral flow technology, where a saliva or swab sample is put into a well, a liquid reagent is added and a line appears in a window indicating positive or negative.
Unlike RT-PCR tests that look for the virus’s genetic material, lateral flow tests tend to look for a protein antigen that lives on a virus’s surface. As these do not amplify the virus, they are less likely to detect lower levels.
Validation
On Monday, the government announced that it had passed its 500,000 daily test target. But insiders say more ambitious end-of-year targets have been scaled back because of the slow rate with which new tests are being cleared for use.
A presentation given by NHS Test and Trace in mid-September, seen by the FT, shows that the government had hoped to run 1.5m tests a day by the end of October, and up to 3m tests a day by the end of January.
A government-backed project called the Condor programme, run by researchers at Oxford and Manchester universities, has drawn much of the criticism for the slow validation process.
Researchers running Condor have acknowledged frustration at the speed, which they share, but said it was absolutely crucial that the tests the population used were sufficiently accurate.
One person involved in the government’s testing strategy said of Condor: “Have you seen a snail go backwards?”
The government has since set up a separate, but parallel, group to validate new technologies, managed out of a Public Health England science park at Porton Down.
The Department of Health said it was working “tirelessly to make sure everyone who needs a test can get one”, including through new technology to “test more people and deliver rapid results”.
https://news.google.com/__i/rss/rd/articles/CBMiP2h0dHBzOi8vd3d3LmZ0LmNvbS9jb250ZW50L2ZmODRkMzkzLTdjODMtNDQ3Yi04MTBmLTNmODE4YjI4ZDgyY9IBP2h0dHBzOi8vYW1wLmZ0LmNvbS9jb250ZW50L2ZmODRkMzkzLTdjODMtNDQ3Yi04MTBmLTNmODE4YjI4ZDgyYw?oc=5
2020-11-04 04:01:17Z
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