Evidence of COVID-19 virus in brain, elsewhere in body

An analysis of tissue samples from the autopsies of 44 people who died with COVID-19 shows that SAR-CoV-2 virus spread throughout the body—including into the brain—and that it lingered for almost eight months. The study was published in Nature.

The blood plasma of 38 patients tested positive for SARS-CoV-2, three tested negative, and plasma was unavailable for the other 3. Thirty percent of the patients were female, and the median age was 62.5 years. Twenty-seven patient (61.4%) had three or more comorbidities. The median interval from symptom onset to death was 18.5 days.

Analysis showed that SARS-CoV-2, as expected, primarily infected and damaged airway and lung tissue. But the researchers also found viral RNA in 84 distinct body locations and bodily fluids, and in one case they isolated viral RNA 230 days after a patient's symptoms began.

The researchers detected SARS-CoV-2 RNA and protein in the hypothalamus and cerebellum of one patient and in the spinal cord and basal ganglia of two other patients. But they found little damage to brain tissue, "despite substantial viral burden."

The investigators also isolated viable SARS-CoV-2 virus from diverse tissues in and outside the respiratory tract, including the brain, heart, lymph nodes, gastrointestinal tract, adrenal gland, and eye. They isolated virus from 25 of 55 specimens tested (45%).

The authors wrote, "We demonstrated virus replication in multiple non-respiratory sites during the first two weeks following symptom onset." They add, "Our focus on short postmortem intervals, a comprehensive standardized approach to tissue collection, dissecting the brain before fixation, preserving tissue in RNA later, and flash freezing of fresh tissue allowed us to detect and quantify SARS-CoV-2 RNA levels with high sensitivity by [polymerase chain reaction] and [in situ hybridization], as well as isolate virus in cell culture from multiple non-respiratory tissues including the brain, which are notable differences compared to other studies."

Sydney R. Stein et al, SARS-CoV-2 infection and persistence in the human body and brain at autopsy, Nature (2022). DOI: 10.1038/s41586-022-05542-y