Highly accurate test for common respiratory viruses uses DNA as ‘bait’ — ScienceDaily

A brand new test that ‘fishes’ for a number of respiratory viruses without delay utilizing single strands of DNA as ‘bait’, and offers extremely accurate ends in below an hour, has been developed by Cambridge researchers.

The test uses DNA ‘nanobait’ to detect probably the most common respiratory viruses — together with influenza, rhinovirus, RSV and COVID-19 — on the identical time. In comparability, PCR (polymerase chain response) exams, whereas extremely particular and extremely accurate, can solely test for a single virus at a time and take a number of hours to return a end result.

While many common respiratory viruses have comparable signs, they require completely different remedies. By testing for a number of viruses without delay, the researchers say their test will guarantee sufferers get the proper therapy rapidly and will additionally cut back the unwarranted use of antibiotics.

In addition, the exams can be utilized in any setting, and will be simply modified to detect completely different micro organism and viruses, together with potential new variants of SARS-CoV-2, the virus which causes COVID-19. The outcomes are reported within the journal Nature Nanotechnology.

The winter chilly, flu and RSV season has arrived within the northern hemisphere, and healthcare staff should make fast choices about therapy when sufferers present up of their hospital or clinic.

“Many respiratory viruses have similar symptoms but require different treatments: we wanted to see if we could search for multiple viruses in parallel,” mentioned Filip Bošković from Cambridge’s Cavendish Laboratory, the paper’s first creator. “According to the World Health Organization, respiratory viruses are the cause of death for 20% of children who die under the age of five. If you could come up with a test that could detect multiple viruses quickly and accurately, it could make a huge difference.”

For Bošković, the analysis can also be private: as a younger little one, he was in hospital for virtually a month with a excessive fever. Doctors couldn’t work out the reason for his sickness till a PCR machine turned obtainable.

“Good diagnostics are the key to good treatments,” mentioned Bošković, who’s a PhD scholar at St John’s College, Cambridge. “People show up at hospital in need of treatment and they might be carrying multiple different viruses, but unless you can discriminate between different viruses, there is a risk patients could receive incorrect treatment.”

PCR exams are highly effective, delicate and accurate, however they require a bit of genome to be copied tens of millions of occasions, which takes a number of hours.

The Cambridge researchers wished to develop a test that uses RNA to detect viruses straight, with out the necessity to copy the genome, however with excessive sufficient sensitivity to be helpful in a healthcare setting.

“For patients, we know that rapid diagnosis improves their outcome, so being able to detect the infectious agent quickly could save their life,” mentioned co-author Professor Stephen Baker, from the Cambridge Institute of Therapeutic Immunology and Infectious Disease. “For healthcare workers, such a test could be used anywhere, in the UK or in any low- or middle-income setting, which helps ensure patients get the correct treatment quickly and reduce the use of unwarranted antibiotics.”

The researchers primarily based their test on buildings constructed from double strands of DNA with overhanging single strands. These single strands are the ‘bait’: they’re programmed to ‘fish’ for particular areas within the RNA of goal viruses. The nanobaits are then handed by way of very tiny holes referred to as nanopores. Nanopore sensing is sort of a ticker tape reader that transforms molecular buildings into digital info in milliseconds. The construction of every nanobait reveals the goal virus or its variant.

The researchers confirmed that the test can simply be reprogrammed to discriminate between viral variants, together with variants of the virus that causes COVID-19. The method permits close to 100% specificity because of the precision of the programmable nanobait buildings.

“This work elegantly uses new technology to solve multiple current limitations in one go,” mentioned Baker. “One of the things we struggle with most is the rapid and accurate identification of the organisms causing the infection. This technology is a potential game changer; a rapid, low-cost diagnostic platform that is simple and can be used anywhere on any sample.”

A patent on the know-how has been filed by Cambridge Enterprise, the University’s commercialisation arm, and co-author Professor Ulrich Keyser has co-founded an organization, Cambridge Nucleomics, targeted on RNA detection with single-molecule precision.

“Nanobait is based on DNA nanotechnology and will allow for many more exciting applications in the future,” mentioned Keyser, who relies on the Cavendish Laboratory. “For commercial applications and roll-out to the public we will have to convert our nanopore platform into a hand-held device.”

“Bringing together researchers from medicine, physics, engineering and chemistry helped us come up with a truly meaningful solution to a difficult problem,” mentioned Bošković, who acquired a 2022 PhD award from Cambridge Society for Applied Research for this work.

The analysis was supported partially by the European Research Council, the Winton Programme for the Physics of Sustainability, St John’s College, UK Research and Innovation (UKRI), Wellcome, and the National Institute for Health and Care Research (NIHR) Cambridge Biomedical Research Centre.

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