A rapid Covid-19 test that uses a laser to detect changes in the blood could identify carriers before they become infectious to others. A team of quantum physicists in the UAE this week claimed their device could be 85 to 90 per cent accurate. QuantLase Imaging Lab, owned by a company listed on the Abu Dhabi stock exchange, said the technology could help to contain the virus until a vaccine becomes available. With results in seconds, it said the technology could be used in mass testing programmes with a high degree of accuracy. But how exactly does it work? <em>The National </em>explains. A machine that tests a drop of blood using a laser beam of light. It was developed by QuantLase Imaging Lab, the medical research arm of International Holdings Company, which has been studying the change in cell structure of virus-infected blood. All that is required is a tiny spot of blood, in the same way diabetics check their glucose levels. That is then collected on a slide, which is inserted into a machine. A laser is then shone on to the blood sample, which projects a pattern that is captured by a camera. This pattern is analysed by an algorithm which compares it with thousands of other samples to determine whether the person is healthy or sick. “There is a significant change between an unhealthy blood cell and a healthy blood cell,” said Dr Pramod Kumar, head of research at QuantLase Lab and a research fellow at University of Exeter in the UK. “Based on this we can distinguish the infected person from a healthy one at a mass level and very quickly.” Blood cells of a healthy person appear perfectly round under laser light, but that ring is destroyed in unhealthy cells, making them look scattered. “If we shine a laser on a blood cell and if there is an infection, the blood cell gets deformed or is changed in shape, size, density, morphology. There are various kinds of changes in a blood cell. And because of this change, light gets scattered,” said Dr Kumar, who is a quantum physicist. “Light gets rebounded and makes a particular pattern on the screen, which will give the signature of the defect of the blood cell due to infection. This is the central idea behind it.” Dr Kumar said it can detect any viral infection in the blood. All viruses have a signature shape, including the coronavirus. And the algorithm searches for what it looks for in the blood. “Covid-19 is specific in its outline,” said Peter Abraham, executive director of lab owner International Holding Group. QuantLase said it is 85 per cent to 90 per cent accurate. “It gives very few false positives, 4 per cent. We are more concerned that no positive people get negative results. We are trying to improve this accuracy and precision,” said Dr Kumar. Up to 10 per cent of samples require retesting as the algorithm cannot determine the result either way. Although standard PCR Covid-19 tests, which search for the DNA of the virus using a nasal swab, are highly accurate when conducted in the lab, they are often far from perfect when used on the ground. Experts say it is not possible to determine the exact false positive rate of PCR tests, but they are estimated to generate false negative results for almost one in three infected people, according to <em>Popular Science</em>. So the 4 per cent false positive rate of the laser Covid-19 test would appear to be a significant improvement. “How is this easier or better than a nasal swab? Significantly. Because a nasal swab takes hours. This fundamentally is done in seconds,” said Mr Abraham. Mr Abraham said its accuracy will also improve over time using artificial intelligence to improve the algorithm’s ability to spot a Covid-19 infected blood cell. “The accuracy at the moment is very strong. This will take it even further because we have an ability to use AI to do that work,” he said. The new technology has been tested against 6,000 samples which have been provided by the UAE government. “We are working in parallel with the government and they are supporting us very well in giving us infected patients’ samples,” said Dr Kumar. “We are at 13 sites,” added Mr Abraham. “We have already tested it on 6,000 patients. And when we say testing, it is working.” He said there has been significant interest in the test since it was announced earlier this week, including among some very big players globally. The company expects to receive the necessary approvals in the “coming weeks”. “The ultimate aim would be to manufacture in the UAE but this is something we need to do worldwide. “We need to share this with the world.”
