Coronavirus: Addenbrooke’s uses University of Cambridge’s new test that diagnoses Covid-19 in four hours
A new test that inactivates the novel coronavirus at the point of sampling has been developed by University of Cambridge researchers and is being used to screen frontline NHS staff at Addenbrooke’s Hospital.
The test is able to diagnose a Covid-19 infection in four hours, whereas the standard test takes more than 24 hours.
And while the infectious nature of the virus means containment level 3 facilities are required to carry out the current procedure, which slows down the process, the new test can be completed in level 2 facilities, which are more widely available and less restrictive.
The modified polymerase chain reaction (PCR) test was developed by a team led by Professor Stephen Baker at the Cambridge Institute for Therapeutic Immunology and Infectious Disease (CITIID), which is at the centre of the university’s response to the virus.
“PCR tests for coronavirus infection are slow because of the safety requirements necessary for handing this potentially lethal virus,” he said. “Now that we are able to inactivate it, we can dramatically improve the turnaround time from swab to result.
“This will be extremely useful in helping test NHS frontline staff and helping clarify whether self-isolating healthcare staff are infected or negative, potentially allowing them to return to work.”
Samples are taken using a nasal swab and the virus is inactivated before being sent to the lab for testing.
Professor Baker said the team has enough reagents – the chemicals used to detect the virus – for 200 samples a day, five days a week, for the next 10-12 weeks, but hopes to expand this capacity.
It is now being used on NHS healthcare workers at Addenbrooke’s and staff who have been asked to isolate due to potential contact with infected individuals.
PCR tests work by extracting a tiny amount of RNA from the virus and copying it millions of times so that it can be detected.
Using a method based on previous work led by Professor Ian Goodfellow and colleagues in the Department of Pathology, the new test was adapted from the in-house, real-time PCR developed in the routine diagnostics laboratory at Addenbrooke’s by Dr Martin Curran.
It has been validated against the approved Public Health England tests following a collaboration between clinical and occupational health staff at Cambridge University Hospitals (CUH) with the university team.
Prof Paul Lehner said: “Organising the logistics for testing has been a huge challenge. But thanks to a tremendous collaborative effort between CUH and the university, we are now testing frontline healthcare workers as well as people who are off work and in isolation due to potential Covid-19 related contacts.”
Cambridge is at the forefront of the government’s five-pillar plan to drive up testing for SARS-CoV-2, the virus that causes Covid-19.
It was announced on Tuesday that the university is working with pharma companies AstraZeneca and GlaxoSmithKline to set up a new testing laboratory at the university’s Anne McLaren Building for high throughput Covid-19 screening.
The lab will also explore the use of alternative chemical reagents for test kits, which are in short supply and typically manufactured abroad, which is causing delays in accelerating testing in the UK.
And last week, university spin-out company Diagnostics for the Real World announced that it had developed a point-of-care, rapid diagnostic test for patients capable of diagnosing Covid-19 in 90 minutes.
The test, also being evaluated at CITIID, runs on SAMBA II machines, 100 of which are being made available to hospitals across the country thanks to a $3million (about £2.4 million) donation from businessman and philanthropist Sir Chris Hohn. Addenbrooke’s obtained the first 10 SAMBA II machines last week for use in wards with suspected Covid-19 patients. The donation will be matched by the purchase of 10 additional machines by the Cambridge Trust.
The machines are used to test patients and frontline NHS workers.
More than 150 workers at CITIID, based in the Jeffrey Cheah Biomedical Centre on Cambridge Biomedical Campus, have joined the fight against Covid-19.
The institute, which opened its doors in September 2019, has redirected all of its research efforts to tackling the pandemic and the university has announced that CITIID is taking a leading role in the £20million Covid-19 Genomics UK Consortium, which is the government-funded national effort to help understand and control the infection.
Director Prof Ken Smith said: “The world is facing an unprecedented challenge, with potentially millions of lives at risk, which is why over 150 of my colleagues at our new institute are focusing their expertise on the fightback against Covid-19.
“Together with our partners in the NHS and NIHR (National Institute for Health Research), we aim to identify those patients at greatest risk and understand why the coronavirus makes some people so sick while leaving others with only mild symptoms. Ultimately, we hope this will lead to the development of new treatments against this dreadful disease.”
CITIID has what is believed to be the largest containment level 3 facility in any UK academic institution.
Professor Gordon Dougan said: “The state-of-the-art facilities and equipment at CITIID will allow us to do essential work on the novel coronavirus in a safe environment. Our institute, positioned as it is on the thriving Cambridge Biomedical Campus, is perfectly suited to lead Cambridge’s response, working with research and health partners locally, nationally and internationally on this urgent problem.”
Covid-19 patients at Addenbrooke’s are now being recruited to help their work.
The team will take blood and other samples from volunteer patients, and these will be processed in the Department of Medicine’s laboratories before being transferred for storage and further study at CITIID.
Samples will be taken when the patients first arrive at the hospital and during the course of the disease.
The study is part of the Covid-19 BioResource, a collaboration with the NIHR National BioResource.
Analysis of the samples will help the team understand how virus infects us and causes disease and better understand how our immune system responds.
The researchers hope to be able to predict which patients will do well or badly, and their findings could inform the development of new treatments.
Prof Lehner said: “A key challenge for the institute is trying to understand how much of the lung disease seen in Covid-19 patients is caused by the virus itself and how much is due to an inappropriate immune response.
“An answer to this question will help guide how best we treat this devastating condition.”