Existing viral RNA tests take 1.5 to 2 hours to give a result. The new test, developed by scientists from the University of Oxford’s Engineering Science Department and the Oxford Suzhou Centre for Advanced Research (OSCAR) in China, works around three times as quick. According to the researchers, the coronavirus test does not require elaborate equipment.
“The beauty of this new test lies in the design of the viral detection that can specifically recognise SARS-CoV-2 (COVID-19) RNA and RNA fragments,” said Prof Wei Huang, one of the research leads. “The test has built-in checks to prevent false positives or negatives and the results have been highly accurate.”
According to the Oxford team, the technology is very sensitive, meaning that patients in the early stages of infection could potentially be identified sooner, helping to reduce the spread of the coronavirus. Current UK testing has been criticised for not being rolled out wide enough, with most members of the public and even many NHS staff not qualifying for testing. The WHO has been vocal that widespread testing is essential in order to identify and contain the spread of the virus.
The Oxford technology requires just simple heat-block that maintains a constant temperature for RNA reverse transcription and DNA amplification, and the results can be read by the naked eye. It uses a simple colour change to identify the presence of the virus. A positive sample changes from pink to yellow. Each test uses three vials, each with different primers. A positive test would turn two vials yellow and leave one pink. This acts as a negative control to confirm the test is working.
The researchers say the new test has been validated with real clinical samples at Shenzhen Luohou People’s Hospital in China. The hospital has used the test kits on 16 clinic samples, including 8 positives and 8 negatives, which have been confirmed by conventional RT-PCR methods and other clinical evidence. The test results using the rapid detection kits were all successful.
“I am proud of our team that have developed a useful technology and can make a contribution in combating CoV-19, and we are very grateful to the hospital’s medical team led by Dr Xizhou Sun, Dr Xiuming Zhang and Dr Dan Xiong for their part in testing this new technology,” said Prof Zhanfeng Cui, director of OSCAR.
The Oxford team is now working to develop an integrated device so that the test can be used at clinics, airports, or even for home use.