Heart damage in long Covid, conceptual illustration. Damaged heart surrounded by SARS-CoV-2 coronavirus particles. Long covid is a complication of Covid-19, a respiratory disease caused by the new coronavirus SARS-Cov-2, which emerged in Wuhan, China, in December 2019. Long Covid refers to ongoing symptoms after the initial respiratory disease has resolved. The most common symptoms are fatigue, shortness of breath and joint pain. Less common symptoms include inflammation of the heart and irregular heart beats.