Autopsies Reveal Startling New Information
By JIM WAPPES, UNIVERSITY OF MINNESOTA
Scientists
from the National Institutes of Health (NIH) tested samples from autopsies that
were performed from April 2020 to March 2021. They conducted extensive sampling
of the nervous system, including the brain, in 11 of the patients.
RNA and viable virus in various organs
All
of the patients died with COVID-19, and none were vaccinated. The blood plasma of 38 patients tested positive for SARS-CoV-2, 3 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 patients (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.”
Possible ramifications for ‘long COVID’
Senior
study author Daniel Chertow, MD, MPH, said in an NIH news release that, prior to the work, “the
thinking in the field was that SARS-CoV-2 was predominantly a respiratory
virus.”
Finding
viral presence throughout the body—and sharing those findings with colleagues a
year ago—helped scientists explore a relationship between widely infected
bodily tissues and “long COVID,” or symptoms that persist for weeks and months
after infection.
Part
of an NIH-funded Paxlovid RECOVER trial that is expected to begin in 2023
includes an extension of the autopsy work highlighted in the Nature study, according to coauthor Stephen
Hewitt, MD, PhD, who serves on a steering committee for the RECOVER
project. Autopsies in the RECOVER trial include people who both
were vaccinated and infected with variants of concern—data that wasn’t
available in yesterday’s study.
“We’re
hoping to replicate the data on viral persistence and study the relationship
with long COVID,” Hewitt said. “Less than a year in we have about 85 cases, and
we are working to expand these efforts.”
Reference:
“SARS-CoV-2 infection and persistence in the human body and brain at autopsy”
by Sydney R. Stein, Sabrina C. Ramelli, Alison Grazioli, Joon-Yong Chung,
Manmeet Singh, Claude Kwe Yinda, Clayton W. Winkler, Junfeng Sun, James M.
Dickey, Kris Ylaya, Sung Hee Ko, Andrew P. Platt, Peter D. Burbelo, Martha
Quezado, Stefania Pittaluga, Madeleine Purcell, Vincent J. Munster, Frida
Belinky, Marcos J. Ramos-Benitez, Eli A. Boritz, Izabella A. Lach, Daniel L.
Herr, Joseph Rabin, Kapil K. Saharia, Ronson J. Madathil, Ali Tabatabai,
Shahabuddin Soherwardi, Michael T. McCurdy, NIH COVID-19 Autopsy Consortium,
Karin E. Peterson, Jeffrey I. Cohen, Emmie de Wit, Kevin M. Vannella, Stephen
M. Hewitt, David E. Kleiner & Daniel S. Chertow, 14 December 2022, Nature.
DOI: 10.1038/s41586-022-05542-y