People living with long Covid after being admitted to hospital are more likely to show some damage to major organs, according to a new study, reports BBC.
MRI scans revealed patients were three times more likely to have some abnormalities in multiple organs such as the lungs, brain and kidneys.
Researchers believe there is a link with the severity of the illness.
It is hoped the UK study will help in the development of more effective treatments for long Covid.
The study, published in Lancet Respiratory Medicine, looked at 259 patients who fell so ill with the virus that they were admitted to hospital.
Five months after they were discharged, MRI scans of their major organs showed some significant differences when compared to a group of 52 people who had never had Covid.
The biggest impact was seen on the lungs, where the scans were 14 times more likely to show abnormalities.
MRI scans were also three times more likely to show some abnormalities in the brain - and twice as likely in the kidneys - among people who had had severe Covid.
There was no significant difference in the health of the heart or liver.
Dr Betty Raman, from the University of Oxford and one of the lead investigators on the study, says it is clear that those living with long Covid symptoms are more likely to have experienced some organ damage.
"Five months after being discharged from hospital for Covid, we found more abnormalities in the lungs, brain and kidneys in those patients than in the group who had never had Covid," she said.
"The patient`s age, how severely ill they were with Covid, as well as if they had other illnesses at the same time, were all significant factors in whether or not we found damage to these important organs in the body."