The study, published in the Lancet Respiratory Diseases journal, examined the condition of 259 patients who became severely ill with the virus and required hospitalization.

Five months after they were discharged from hospital, an MRI scan of their vital organs showed some significant differences compared to a group of 52 people who did not have Covid.

The biggest effect was seen in the lungs, where scans were 14 times more likely to show abnormalities.

MRI scans showed that those who developed severe Covid symptoms were three times more likely to show certain brain abnormalities and twice as likely to have kidney problems.

There was no significant difference in heart or liver health.

Dr Petty Raman, from the University of Oxford, says it is clear that people with long-term Covid symptoms are more likely to develop some organ damage.

“The age of the patient, how severe Covid they have, and whether they have other illnesses at the same time are important factors in whether or not there is damage to these vital organs in the body,” he said.

The findings are part of a larger study looking at the long-term effects of Covid on hospital admissions called the BeHosp Covid Study.

The researchers found some symptoms similar to those of organ damage revealed by MRI scans, for example, chest tightness and coughing with abnormalities in the lungs. But not all symptoms experienced by long-term Covid sufferers can be directly linked to what is seen on scans.

Abnormalities in more than one organ are more common among hospitalized patients, who report physical and mental problems even after recovery from the initial infection, Raman said.

“What we see is that people with organ damage detected on MRI, meaning they have more than two organs affected, are four times more likely to report severe and very severe mental and physical impairment,” he said.

“Our findings also highlight the need for long-term multidisciplinary follow-up services focusing on lung and lung health (kidney, brain and mental health), especially for those hospitalized with Covid,” he added.

The research is part of a wider effort to understand the range of different symptoms that make up the syndrome known as prolonged Covid, led by Professor Chris Brightling from the University of Leicester, lead researcher on the BehospCovid study.

“This comprehensive whole-body imaging study confirms that changes in multiple organs appear months after hospitalization due to Covid,” he said.

“The BioHosp Covid study is working to understand why this happens and how we can develop new tests and treatments for prolonged Covid,” he added.