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Rapid coronavirus test trials missed more than 50 per cent of positive cases 

Operation Moonshot has come crashing down to Earth in Liverpool as one of the rapid coronavirus tests that was lined up for a mass-testing scheme has been revealed not to work.

Officials in the city have now cancelled plans to start a huge trial of Optigene Direct RT-Lamp tests, bought because they give swab results in just 20 minutes.

But, catastrophically, the tests have missed more than 50 per cent of positive cases in a trial in Manchester, meaning they risk dangerously undermining the number of people who are actually infected.

Trials in Salford were scaled back after just six weeks, in part due to concerns about the accuracy of the OptiGene Lamp test, according to The Guardian.

Scientists on Greater Manchester’s Mass Testing Expert Group reported a positive-detecting accuracy of just 46.7 per cent and found that ‘a high proportion of samples collected from infected individuals in a ‘real world’ setting would not be detected’. 

Liverpool City Council has now said it will not use the tests which, it had been hoped, would form part of the city’s pilot of whole-city testing which starts today.

All of the city’s 500,000 residents are being encouraged to get swab-tested for Covid-19 during the lockdown as walk-in test sites are springing up across the city. It is the first time the Government has opened testing up to members of the public who don’t have symptoms of disease.

Liverpool today becomes the first city in England to open up coronavirus testing to all of its residents, regardless of whether they have symptoms or not (Pictured: A testing centre at Stanley Park near Anfield)

The military have been drafted in to help with the mass testing scheme and three soldiers are pictured at Pontins holiday park at Ainsdale Beach in Southport

The military have been drafted in to help with the mass testing scheme and three soldiers are pictured at Pontins holiday park at Ainsdale Beach in Southport

A testing centre is pictured in Wavertree in Liverpool. The city's 500,000 residents will be able to get tested with rapid swab-testing machines as well as the usual PCR swab tests which take a few days to return results

A testing centre is pictured in Wavertree in Liverpool. The city’s 500,000 residents will be able to get tested with rapid swab-testing machines as well as the usual PCR swab tests which take a few days to return results

The findings of the Manchester trial raise major questions about one of the main tests in the Government’s mass-screening strategy, which Boris Johnson this week heralded as the UK’s main route back to normality.

The Department of Health has disputed the results, calling them ‘incorrect’ and maintaining that the test is good. 

But in a letter seen by the Guardian, scientists from the Manchester group (MTEG) said: ‘The current available data from the Manchester pilot shows low sensitivity (46.7 per cent) of the Direct RT-Lamp platform.’

According to the newspaper, the scientists said they had ‘significant concerns’ and felt the data did not support a large scale rollout of the tests to staff in clinical settings, such as hospitals and care homes.

Plans being developed under Operation Moonshot will reportedly see 10 million people tested every day at a cost of £100 billion.

On Thursday, Prime Minister Boris Johnson said that technical advances in testing, including a different type of rapid testing being piloted in Liverpool, could be a ‘real way forward through the crisis’.

Pregnancy-style lateral flow tests that give results in minutes and can be carried out without supervision are part of pilot schemes across the city.

Mr Johnson told a Downing Street press conference: ‘These really are full of promise, I do think that testing does offer a real way forward for this country.’

He said mass rapid testing would allow a return towards normal life.

‘The advantage of this approach is that you can tell whether people are infectious or not immediately, within 10 to 15 minutes,’ he said.

‘Without having to worry about the time taken to get the answer from the current testing system, you can help those people to self-isolate if they test positive, and if they test negative, then of course, they’re free to do things with other people who test negative in something close to a normal way.’

However, some experts have urged caution, saying rapid tests are not as accurate as standard PCR swab tests processed in the lab and could result in people who are infectious being told they are not.

Professor Mark Wilcox, co-chair of DHSC’s Technical Validation Group, said a pilot of the rapid LAMP test used in Manchester but carried out elsewhere showed it had an overall sensitivity of nearly 80%, rising to over 96% for individuals with a higher viral load.

‘The direct LAMP tests used in Manchester have been validated in other laboratories and in real-world testing for use in different settings,’ he said.

‘It is incorrect to claim the tests have a low sensitivity, with a recent pilot showing overall technical sensitivity of nearly 80% rising to over 96% in individuals with a higher viral load, making it important for detecting individuals in the infectious stage.

‘The challenge now is to understand the reasons for the difference in claimed sensitivity in one evaluation versus those in multiple others.’

Read more at DailyMail.co.uk


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