Researchers from the Centers for Disease Control and Prevention, the University of Utah in Salt Lake City, and Columbia University in New York City, USA, determined that children are as likely to contract COVID-19 as children. adults, but it is cases of minors are much more likely to be asymptomatic. To reach this conclusion, the specialists collected data from households in Utah and New York.
In this way, they found that age has little effect on a person’s chances of contracting the virus. However, they confirmed that younger people were significantly less likely to suffer from severe symptoms from the virus, But the highlight was that only half of the children who contracted the virus had a symptomatic case, compared with 88% of adults.
The study findings add to the growing body of evidence that children and adolescents generally are safer from the virus than older people and have a low risk of serious complications or death.
The researchers published their findings in JAMA Pediatrics. The study covered 1,236 people from 310 households and consisted of asking participants to regularly collect nasal swabs to test for the virus, between September 2020 and April 2021. They also completed surveys reporting possible COVID-19 symptoms they were experiencing.
Overall, of the participants in New York, there were 7.7 positive cases per 1,000 people, double the rate of 3.8 cases per 1,000 that occurred in Utah. New York City, in general, has proven to be one of the US COVID-19 hot spots due to its population density. The researchers combined data from both cities and divided the participants into age cohorts.
In the case of children 0 to 4 years old, 6.3 out of every 1,000 contracted the virus during the study period. Additionally, 4.4 out of 1,000 children ages 5 to 11 and 6 out of 1,000 children ages 12 to 17 tested positive for COVID-19.
Adults included in the study had similar rates of COVID-19, with 5.1 in 1,000 contracting the virus. Although the infection rates were similar, the children who were infected were in much better health than the older ones.
Half of the children in the two youngest age groups, 0-4 and 5-11, were asymptomatic when contracting the virus.
Even the slightly older children in the study, those ages 12 to 17, had high rates of asymptomatic cases, and 45% of those infected did not present any symptoms.
However, the numbers were drastically different for the adults in the study. Only 12% of the adults in the study had asymptomatic cases because the virus is much more difficult for older people to treat.
“A larger fraction of SARS-CoV-2 infections in children were asymptomatic and probably would not have been detected without the study’s evidence, supporting the hypothesis that (COVID-19) infections among children have not been substantially determined during the COVID-19 pandemic, “ wrote the researchers in Jama.
The reasons why children are at less risk of severe illness were explained by several studies. One of them published in the JCI Insight magazine was led by Betsy Herold, a scientist at the Albert Einstein College of Medicine in New York. He found that children have particularly strong mucosal immunity. They pointed out that boys have mucous membranes that act like the layered “stone walls” that protected medieval cities from invaders. They are made up of epithelial cells – which also line many internal organs – that coexist with dendritic cells and macrophages of the immune system, according to Dr. Herold.
Protein-covered epithelial cells act as sentinels. When they detect something strange, such as a new virus, they alert cells to start releasing proteins called “interferons”, which help coordinate the body’s immune response.
Meanwhile, another finding of COVID-19 in children was recently published in the journal Nature Biotechnology by scientist Roland Eils and his colleagues from the Center for Digital Health, which depends on the Berlin Health Institute in Germany. They found that children’s upper airways are “pre-activated” to fight the coronavirus. Their airways are packed with sentinel cells, including some that are excellent at recognizing the coronavirus.
That presence allows children to immediately activate their innate immune systems, releasing interferons that help stop the virus before it can establish itself, Eils said. In contrast, adults have far fewer sentinels on surveillance and take about two days to respond to the virus. By the time those cells are activated in adults, the virus may have multiplied exponentially, and control becomes much more difficult.
When innate immunity fails to control a virus, the body can turn to the adaptive immune system, the second line of defense that adapts to each unique threat. The adaptive system creates antibodies, for example, tailored to every virus or bacteria that the body encounters.
But with the massive arrival of the Delta variant, the number of cases of sick and even hospitalized children in the United States began to increase. New studies indicated that one of the reasons that could influence the development of severe conditions in childhood is related to diseases or syndromes that children already have before infection by the coronavirus. Found between 30% and 70% of hospitalized children with COVID-19 in the United States had underlying conditions that increase their risks, such as Down syndrome, obesity, lung disease, diabetes, or immunodeficiencies. Premature babies are also at higher risk, as are children who have undergone cancer treatment.
Although in the US where the study was carried out, all adults have the possibility of being vaccinated against COVID-19, there are wide sectors that reject them. Regarding children ages 5 to 11, who may be vaccinated when the FDA approves their application, the relatively low severity of COVID-19 cases among boys has left many parents wondering if they need to even vaccinate their children. when available. L surveys show that parents of children seem to be evenly divided on whether or not they will get the COVID-19 vaccine. A survey, conducted by the National Child Health Survey from CS Mott Children’s Hospital in Michigan Medicine in July, indicated that 39% of parents said their children of receiving age had already been inoculated with a coronavirus vaccine. However, 40% of parents also said it was “unlikely” that their children would be vaccinated.
Although children are the least at risk from contracting coronavirus, specialists believe that their vaccination will help stop the pandemic, since they are usually transmitters of the virus to their relatives.
In the US, the FDA regulatory agency is considering giving emergency approval to the Pfizer-BioNTech vaccine for children between 5 and 11 years old, which is expected to occur at the end of this month. In that country, adolescents 12 years of age and older can already receive it.
In Argentina, the approval of the Sinopharm vaccine for children between 3 and 11 years old was announced on October 1. For teens ages 12 to 17, Pfizer and Moderna are approved.