The Covid-19 virus does not confine itself to our nose or our throat : it also lodges in our brain. This was discovered by researchers working for the US government.
Damage to lung tissue and airways
These scientists analyzed biopsies from 44 deceased people who contracted Covid-19. Their autopsies were performed between April 2020 and March 2021. These researchers also sought to study the influence of the SARS-CoV-2 virus on the nervous system. The results of their work have been published in the scientific journal Nature on December 14, 2022.
Note: none of the deceased were vaccinated against Covid-19. 30% of them were women, their median age was 62.5 years and 27 of them had at least three comorbidities. Analysis of their biopsies show lesions in lung tissue and in the respiratory tract.
SARS-CoV-2 present in brain and gastrointestinal tract
Scientists also detected RNA and proteins from SARS-CoV-2 in the hypothalamus (the part of the brain that controls the endocrine system and the vegetative nervous system) and in the cerebellum of one of the deceased. They also found some in the spinal cord and in the basal ganglia (a network of deep structures in the brain) of two other people. The brain tissue was however little damaged, “despite a substantial viral load”.
The Covid-19 virus was also present in other tissues outside the respiratory tract, such as heart, lymph nodes, gastrointestinal tract, adrenal gland and the eyes.
Future possibilities to study the causes of the long Covid
Until now, “experts thought that SARS-CoV-2 was essentially a respiratory virus”, reacted one of the study authors, Dr. Daniel Chertow, public health researcher. Having identified the presence of this virus in several parts of the body may in the future be useful to scientists working on the links between tissue infection and “long Covid” (or at least between tissue infection and persistence of symptoms several months after infection).
“Our results show that in some patients, SARS-CoV-2 can cause a systemic infection and remain in the body for months”, say the researchers. However, they qualify: the people concerned by the autopsies were all unvaccinatedwith health concerns and were relatively old.
Logically, these results cannot be extended as they stand to younger, healthy or vaccinated people. Otherwise, researchers are uncertain whether the same findings can be seen with other variants of Covid-19. New studies are therefore needed to understand the migration of SARS-CoV-2 in our body.