COVID-19 is a disease caused by a virus called SARS-CoV-2. The virus – and your immune system’s reaction to it, inflammation – can damage your lungs, causing them to scar and stiffen or fill with fluid.

This video is by the National Heart, Lung, and Blood Institute (NHLBI), part of the National Institutes of Health (NIH).

Learn more: https://www.nhlbi.nih.gov/coronavirus
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