Covid-19 is above all a respiratory disease, but in people who did not survive it, American researchers observed that the virus was present throughout the body: from the eyes to the brain via the testicles.
Covid-19 essentially causes respiratory symptomsyet autopsies performed on people who died of the disease show that the virus is “ capable of spreading throughout the body “. A group of researchers attached to the National Institutes of Health (NIH), whose headquarters is located in Bethesda in the United States, carried out 44 analyzes post mortem on unvaccinated patients who died in hospital and searched for the presence of SARS-coV-2 throughout the human body. The chosen patients were between 40 and 70 years old and had been infected with SARS-CoV-2 for 8 to 18.5 days at the time of their death.
Scientists have confirmed the presence of the coronavirus in 84 different anatomical locations, both tissues and biological fluids. The respiratory system remains the group of organs most affected by viral infection, but the coronavirus has also been identified in the eyes, skin, muscles and even the brain. These results appeared in Nature.
Coronavirus present from head to toe
Among the 44 bodies available to scientists, samples from the brain were only possible on 11 of them. In 90% of cases, the coronavirus was present in the brain, in particular in the hypothalamus and the cerebellum for patients who died of a particularly virulent infection, and in the cervical spinal cord as well as in the basal ganglia (a structure deep brain) in patients for whom the infection was longer.
This research shows that, if the coronavirus replicates preferentially in the respiratory sphere, it can spread throughout the body. Coronavirus subgenomic RNA (a type of RNA produced only during active virus replication) has been isolated from almost all tissues analyzed and in some biological fluids such as the plasma or fluid accumulated in the lungs as a result of illness (pleural fluid). The scientists also succeeded in reculturing SARS-CoV-2 virions isolated from the heart, lymph nodes or even the digestive tract of autopsied patients. This suggests that regions of the body other than the respiratory sphere can serve as a “virus factory”.
This study improves our knowledge regarding the spread of the coronavirus in the human body. Nevertheless, it was done on patients who died between 2020 and 2021, so before the appearance of the Omicron sub-variants – the latter might have a different behavior. In addition, 60% of people autopsied had several comorbidities that might influence the spread of the virus in the body.
