Autopsy reveals COVID-19 virus in brain, elsewhere in body

An analysis of tissue samples from autopsies of 44 people who died of COVID-19 showed that the SAR-CoV-2 virus spreads throughout the body—including into the brain—and the virus persists for nearly eight months. The study was published in Nature.

Scientists from the National Institutes of Health (NIH) examined autopsy samples taken between April 2020 and March 2021. They conducted extensive sampling of the nervous system, including whole brain, in 11 patients.

RNA and viruses are viable in different organs

All the patients died from COVID-19 and no one was vaccinated. The plasma out of 38 patients who tested positive for SARS-CoV-2, three tested negative and there was no plasma for the remaining 3.

Thirty percent of the patients were female and the mean age was 62.5 years. 27 patients (61.4%) had 3 or more comorbidities. The mean time from symptom onset to death was 18.5 days.

Analysis shows that SARS-CoV-2, as expected, mainly infects and damages the airways and lung tissue. But the researchers also found viral RNA in 84 distinct body sites and body fluids, and in one case isolated the viral RNA 230 days after a patient’s symptoms began. head.

Researchers detected SARS-CoV-2 RNA and proteins in the hypothalamus and cerebellum of one patient and in spinal cord and basal ganglia of two other patients. But they found little brain tissue damage, “despite a significant viral burden.”

Investigators have also isolated viable SARS-CoV-2 virus from various tissues inside and outside the body. Respiratoryincluding brain, heart, lymph nodes, gastrointestinal tract, adrenal glands and eyes. They isolated the virus from 25 of the 55 samples tested (45%).

“We demonstrated viral replication in multiple non-respiratory sites during the first two weeks after symptom onset,” the authors wrote.

They added: “We focused on short periods of time after death, a comprehensive standardized approach to tissue collection, brain dissection prior to fixation, tissue preservation in RNA afterwards, and Rapid freezing of fresh tissue allows us to detect and quantify SARS-CoV-2 RNA levels with high sensitivity via [polymerase chain reaction] and [in situ hybridization]as well as virus isolation in cell culture from a variety of non-respiratory tissues including the brain, which are notable differences from other studies.”

Possible ramifications for prolonged COVID

Senior study author Daniel Chertow, MD, MPH, said in an NIH press release that, prior to conducting the study, “the thinking in this area was that SARS-CoV-2 was primarily a type of coronavirus. respiratory viruses.”

Finding the virus’s presence throughout the body—and sharing those findings with colleagues a year ago—helped scientists explore the relationship between widely infected body tissues and ” persistent COVID” or symptoms that persist for weeks and months after infection.

Part of the Paxlovid RECOVERY trial slated to begin in 2023 includes the extension of the autopsy work outlined in section Nature study, according to co-author Stephen Hewitt, MD, Ph.D., who serves on the steering committee of the RECOVER project. Autopsies in the RECOVER trial included people who had been vaccinated and were infected with worrisome variants—data not available in yesterday’s study.

“We hope to replicate the virus persistence data and study the relationship with COVID,” Hewitt said. “Less than a year later, we have about 85 cases and we’re working to expand these efforts.”