A lung study of people who died from Covid-19 found persistent and widespread lung damage in most cases.
The findings can help doctors understand what is behind a syndrome called “long covid”, in which patients experience symptoms continuously for months.
The scientists leading the study said they also found some specific characteristics of SARS-CoV-2, the virus that causes Covid-19, which may explain why it can be as harmful as so.
Mauro Giacca, a professor at King University, said: “The findings indicate that Covid-19 is not simply a disease caused by the death of cells infected with the virus, but likely a posterity. results of these abnormal cells persisting in the lungs. London, co-lead the work.
The research team analyzed tissue samples from the lungs, heart, liver and kidneys of 41patients who died from Covid-19 at Trieste University Hospital in Italy from February to April 2020.
Professor Giacca said that while his team found no overt signs of viral infection or prolonged inflammation in other organs, they found “really big destruction on ants. structure of the lung “, with healthy tissue” completely replaced by scar tissue “.
“It is highly predictable that one of the reasons why there have been cases of prolonged covid is because the lungs (tissue) are so badly damaged,” he told Reuters.
“Even if someone recovers from Covid, the damage caused can be enormous.”
There is increasing evidence from around the world that a small proportion of people who have previously infected Covid-19 and recover from their initial infection may experience a persistent range of symptoms including fatigue. , brain fog and shortness of breath. This condition is often referred to as “long covid”.
Professor Giacca said that nearly 90% of the 41 patients had some specific characteristics of Covid-19 compared with other forms of pneumonia.
One is a patient with a blood clot in the pulmonary and venous arteries. Another cause is that a number of lung cells are abnormally large and have multiple nuclei – the result of fusing different cells into single large cells in a process called syncytium.
Research published in the Lancet eBioMedicine also found that the virus itself persisted in many types of cells.
Professor Giacca said: “The presence of these infected cells can cause important structural changes in the lungs that can persist for weeks or months and may eventually account for “Long Covid”.