‘You cannot fight a fire blindfolded’, said WHO chief Tedros Adhanom Ghebreyesus. Without testing, those who are infected cannot be isolated, and hence the spread of the virus cannot be halted. Efficient testing is the key to stopping an epidemic from the beginning, with its positive effects evident in nations such as China, South Korea and Singapore.
As the WHO and scientists around the world urge nations to maximise testing as the COVID-19 pandemic unfolds, a new method of testing has been developed by University of Oxford’s Department of Engineering, and The Oxford SuZhou Centre for Advanced Research (OSCAR), situated in China.
What does this mean for testing?
Testing times of the new method are over three-times faster than current viral RNA detection tests, reports the team led by Prof. Zhangfeng Cui and Prof. Wei Huang. Results are available in just over half an hour, as opposed to the 1.5 to 2 hours of previous methods, with a promising level of accuracy as shown through trials with real clinical samples from Shenzhen Luohu People’s Hospital in China.
‘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. The test has built-in checks to prevent false positives or negatives and the results have been highly accurate.’ says Prof. Wei Huang.
Why does it matter?
The new testing methods are not only quicker and more convenient, it is also highly sensitive. Infection may therefore be identified at sooner stages, potentially decreasing the spread of this highly infectious virus.
Quicker testing could make all the difference to frontline NHS workers. Under current government advice, they have to take themselves out of the workforce and self-isolate if they come into close contact with anyone with the virus or exhibit any symptoms, in order to prevent infecting patients in vulnerable groups.
Current methods of detection involve real-time RT-PCR (reverse transcription polymerase chain reaction) of respiratory samples, which can be a sputum sample or a swab in the back of the throat or nose. Viral RNA within the samples are reverse transcribed into cDNA, enabling genes specific to beta coronaviruses and to COVID-19 to be amplified, ultimately allowing the original viral RNA to be quantified and analysed.
The new technology enables reverse transcription of viral RNA and amplification of the resulting DNA with a simple heat-block, which is required to maintain a constant temperature. The rapid results can then be interpreted by the naked eye. The lack of complicated equipment involved in the new testing method means that the test may be helpful in rural areas, with the Oxford scientists now working to develop rapid testing kits suitable for use in airports, and potentially in homes.