Guy's and St Thomas' prove effectiveness of new COVID-19 test

Clinical researchers at Guy’s and St Thomas’ NHS Foundation Trust have proved a new COVID-19 test to be effective at identifying patients that might transmit the virus.

The researchers were the first to evaluate of the effectiveness of the first British tests to be validated in the laboratory by Public Health England, and produced by British-based SureScreen Diagnostics.

Earlier this week, the UK government announced it has purchased 20 million of the SureScreen lateral flow antigen tests which give a result in under half an hour.

Since June 2020, the research team, working with scientists at King’s College London, have been helping improve the accuracy of this antigen test and working to see if can be safely used in hospitals.

The Guy’s and St Thomas’ team, led by Professor Jonathan Edgeworth, consultant microbiologist, first helped the test achieve a CE marking (a European safety accreditation). They then assessed a number of different lateral flow tests alongside the gold-standard polymerase chain reaction (PCR) method in the laboratory. They compared the different tests for their ability to identify patient swabs that contain infectious SARS-CoV-2 virus (the virus which causes COVID-19).

Their research found that although the SureScreen and other lateral flow tests were not as sensitive as the PCR tests, they did successfully identify samples with live virus in them. This means that the test picks up patients that are most likely to transmit the virus.  They also predicted that the tests would help clinical and infection control teams in the hospital.

On 31 December 2020, the SureScreen test began to be embedded into the Guy’s and St Thomas’ emergency department (A&E). The test is now being used on about 700 patients each week to rapidly identify symptomatic patients with COVID-19. It also helps to identify a few COVID-19 patients in A&E each day who often have mild or no symptoms but could still potentially transmit COVID-19 when they are admitted to hospital.

When the test was carefully embedded in the clinical assessment process, it was found to be safe and effective for use in A&E.

The Guy’s and St Thomas’ team have now linked the test results into patients Electronic Health Record (EHR). EHR is a system which securely stores patient data and information, so that it can be securely shared with patients and clinicians. In a hospital this helps to provide more coordinated and efficient care to patients.

Jonathan Edgeworth, consultant microbiologist at Guy’s and St Thomas’ and professor of clinical infectious diseases at King’s College London, said: “It is fantastic that we have been able to support the implementation of this new, fast antigen test, which we have shown is both safe and effective to use in the hospital. Our team have also overcome the challenge of getting rapid electronic recording and communication of results from wherever they are performed, which had been a major barrier to their widespread use.” He added: “I hope these advances can help with rolling out this test to other hospitals and perhaps more widely as part of mass population testing in schools and across the community.”