The cause of death from COVID-19 is the accumulation of the coronavirus itself in the lungs, according to experts from New York University. This contradicts the current versions that the patient is killed by concomitant infections or an autoimmune reaction. The researchers tell more about this in an article in the journal Nature Microbiology.
The researchers took samples of the lung contents of 589 patients who were on a ventilator. In 142 of them, who underwent bronchoscopy, it was also possible to obtain samples of the contents directly from the lower respiratory tract.
The scientists determined the microbial composition of the samples, and also studied the state of immune cells. In those who eventually died, the number of viral particles in the lower respiratory tract was on average 10 times greater than in the survivors. At the same time, the researchers did not find a noticeable difference in the composition of bacteria and fungi in the samples of the deceased and survivors. This may be a consequence of the course of antibiotics that all seriously ill patients received, but, in any case, a bacterial infection in these cases could hardly be recognized as the cause of death of patients.
The researchers also found no significant autoimmune reactions. At the same time, the production of proteins important for “memorization” was reduced by 50% in the deceased patients" new microbes and preparing the body to counteract them. Apparently, violations of the adaptive immunity allow viral particles to accumulate in the lungs, which leads to death, the authors of the work believe.
The use of antiviral drugs for seriously ill patients on a ventilator is not welcome now – there are no specialized remedies for COVID-19 yet, and other means can worsen the patient’s condition due to side effects. However, it is possible that the drugs will still have a positive effect, the researchers admit. They also hope that they will be able to find a way to strengthen adaptive immunity and help the body fight infection.
