The coronavirus that causes COVID-19, SARS-CoV-2, can spread within days from the airways to the heart, brain and almost every organ system in the body, where it may persist for months, a study has found.

In what they describe as the most comprehensive analysis to date of the virus’s distribution and persistence in the body and brain, scientists at the U.S. National Institutes of Health said they found the pathogen is capable of replicating in human cells well beyond the respiratory tract.

The results, released online Saturday in a manuscript under review for publication in the journal Nature, point to delayed viral clearance as a potential contributor to the persistent symptoms wracking so-called long-COVID sufferers. Understanding the mechanisms by which the virus persists, along with the body’s response to any viral reservoir, promises to help improve care for those afflicted, the authors said.