Detect Covid with swab samples from mobiles

A team of researchers has developed an accurate, non-invasive, and low-cost method of testing for Covid-19 using samples taken from the screens of mobile phones.

The team led by University College London researchers analysed swabs from smartphone screens rather than directly from people, and found that people who tested positive by the regular nasal swabbing PCRs were also positive when samples were taken from phone screens. The new method - known as Phone Screen Testing (PoST) - detected the Covid-19 virus on the phones of 81 to 100 per cent of contagious people with a high viral load, suggesting it is as accurate as antigen lateral flow tests.

The PoST is an environmental test, rather than a clinical test, and it is both non-invasive and less expensive than a traditional nasal swabbing PCR. This means not only is it suitable for rollout in lower-income countries, but it also removes the discomfort of current Covid-19 testing options, potentially increasing take-up of regular testing among the general population. In addition, PoST sampling takes less than a minute and does not require medical personnel, which eases mass adoption in big facilities and large-scale applications, the researchers said. The findings are published in the journal eLife.

"Like many, I was very worried about the economic and social impact that the pandemic would leave behind, particularly in lower-income countries. We knew that the only effective way to stop the spreading is to regularly test as many people as possible, but this was not happening because it's too expensive and uncomfortable," said Rodrigo Young from the UCL Institute of Ophthalmology, who led the research at Diagnosis Biotech, a Chilean startup.