Researchers have identified significant abnormalities in the lungs of coronavirus infected people. In some cases, significant damages were seen in the lungs.
The experts of Oxford University conducted the research. They used a novel scanning technique to identify the damages not picked up by conventional scans, reports BBC.
Covid-19 could be causing lung abnormalities still detectable more than three months after patients are infected, researchers suggest.
They used a gas called xenon during MRI scans to create images of lung damage.
Lung experts said a test that could spot long-term damage would make a huge difference to Covid patients.
The xenon technique sees patients inhale the gas during a magnetic resonance imaging (MRI) scan.
Prof Fergus Gleeson, who is leading the work, tried out his scanning technique on 10 patients aged between 19 and 69.
Eight of them had persistent shortness of breath and tiredness three months after being ill with coronavirus, even though none of them had been admitted to intensive care or required ventilation, and conventional scans had found no problems in their lungs.
The scans showed signs of lung damage - by highlighting areas where air is not flowing easily into the blood - in the eight who reported breathlessness.
The results have prompted Prof Gleeson to plan a trial of up to 100 people to see if the same is true of people who had not been admitted to hospital and had not suffered from such serious symptoms.
He is now planning to work with GPs to scan people who have tested positive for Covid-19 across a range of age groups.