A study of the lungs of people who have died from COVID-19 has found persistent and extensive lung damage in most cases and may help doctors understand what is behind a syndrome known as 'long COVID', in which patients suffer ongoing symptoms for months. Scientists leading the research said they also found some unique characteristics of SARS-CoV-2, the virus that causes COVID-19, which may explain why it is able to inflict such harm. "The findings indicate that COVID-19 is not simply a disease caused by the death of virus-infected cells, but is likely the consequence of these abnormal cells persisting for long periods inside the lungs," said Mauro Giacca, a professor at King’s College London who co-led the work.