Since the coronavirus outbreak began, scientists have tried to find out why children are much less likely than adults to experience serious complications from the infection.
Children make up only a small proportion of those infected with SARS-CoV-2, the coronavirus that causes COVID-19. According to data from NYC Health + Hospitals, a New York City health institution, the risk of complications and death progressively increases with age, as does the fact of suffering from an adjacent disease; In statistics, young people under 17 years of age account for a negligible percentage of all deaths from COVID-19 (0.06%) while adults over 75 years of age account for 48.7% of deaths.
Several hypotheses have been proposed to explain why children do not get so seriously ill . These include the possibility that they have a stronger and more effective initial immune response to the virus than adults (therefore they go through with fewer complications than adults viral diseases such as measles); and that they may have some immunity from recent exposure to similar viruses (some types of coronaviruses that cause common colds have characteristics in common with SARS-CoV-2, and may have created cross-immunity).
Now, new recent scientific research indicates that the answer could lie in healthy blood vessels in children. The journal Nature published in mid-June a comprehensive report that summarizes the studies in this regard.
As Frank Ruschitzka, a cardiologist at Zurich University Hospital in Switzerland, explains to Nature , many critical COVID-19 adults experience clotting in their blood vessels, leading to heart attacks or strokes. Clotting appears to be related to a malfunction of the endothelium, the smooth tissue that lines blood vessels and that normally prevents clotting.
Ruschitzka led a study showing how SARS-CoV-2 can infect endothelial cells, which are found throughout the body. To understand it better, we must imagine the endoletium as a tissue that ‘covers’ or covers all blood vessels.
As well; In a study of three people with COVID-19, two of whom died, Ruschitzka’s team found that SARS-CoV-2 had infected the patient’s endothelium and caused inflammation and signs of clotting. According to Marcel Levi, a hematologist at University Hospital London, this theory could also explain why people with conditions that compromise the endothelium, such as diabetes and hypertension, are at higher risk of severe COVID-19.
Related to this, COVID-19 in critically ill patients has also been linked to the formation of thrombi: on March 9, The Lancet magazine published a study by Chinese scientists in which they documented the alteration of coagulation that led to thrombus formation in the most seriously ill, in a sample of 191 Chinese patients, 54 of whom died during the month of January.
How is the endothelium of children?
According to Paul Monagle, a pediatric hematologist at the Melbourne Children’s Campus, the endothelium is typically in better condition in children than in adults. A child’s endothelium is perfectly configured, ‘brand new’, and then deteriorates with age. Monagle believes that children’s blood vessels can resist a viral attack more efficiently in adults. One observation that supports this hypothesis is that few children with COVID-19 have excessive clotting and damaged blood vessels.
Rejuvenate the endothelium, a possible treatment route
Now, Monagle is trying to understand what happens when the virus enters endothelial cells. The virus likely disrupts communication between cells, platelets, and plasma components involved in clotting, and this breakdown in communication would lead to excessive clot formation. The hematologist hopes that the study of samples from children will offer clues about what is happening in some adults, and also possible therapeutic options: “If we understand what happens to children, a possible treatment route could be to rejuvenate the endothelium of the Adults”.
