SARS-CoV-2 can travel from the lungs to the heart, brain, and nearly every organ system in the body. The coronavirus can replicate in human cells outside of the respiratory system. Understanding how the virus survives could lead to better treatment for those who are infected. The findings are primarily based on data from fatal Covid cases, not long Covid patients. All six autopsy patients who died more than a month after exhibiting symptoms had SARS-CoV-2 RNA found in their brains. One patient died 230 days after the onset of symptoms, implying that extended Covid can last weeks or months. To identify and quantify viral levels, NIH researchers used a range of tissue preservation techniques.