The AI system on the Tianhe-1 computer can go through hundreds of images generated by computed tomography (CT) and gave a diagnosis in about 10 seconds, according to the National Supercomputer Centre in Tianjin, which hosts the machine. The accuracy of the analysis was higher than 80 per cent “and increasing steadily every day”. China has offered free use of the machine around the world, but US Centres for Disease Control says it does not recommend using scans to diagnose Covid-19.