How long does natural immunity to COVID last in children, according to science

One of the great unknowns about COVID-19 is related to how long each person remains immune to infection, both in those who have the disease and those who have been vaccinated with one of the available formulations.

To analyze what is happening among children with this issue, a team of researchers from Texas Health Houston University, in the US, analyzed data from 218 children throughout the state of Texas.

And they concluded that children previously infected with COVID-19 develop natural circulating antibodies that last at least seven months, as published in the journal Pediatrics.

For the study, experts analyzed data from children between the ages of five and 19 who enrolled in the Texas CARES survey, which had begun in October 2020, with the aim of assessing the status of antibodies to SARS-CoV-2 over time among a population of adults and children.

The volunteers provided the researchers with three separate blood draws, in samples that were collected prior to vaccination but also during waves of the Delta and Ómicron variants.

To date, researchers have completed three different phases of the study, and so far data showed that while 96% of people infected with coronavirus maintained antibodies until seven months later, more than half (58%) of the sample tested negative for infection-induced antibodies in its third and final measurement. The results do not include the impact of vaccine protection.

“Information on the durability of natural immune responses specific to SARS-CoV-2 in children is important to inform strategies for pediatric vaccination and mitigation of community transmission, both for current variants and for possible future variants,” stressed the authors in the publication of their conclusions.

However, they stressed that “the actual incidence and longitudinal presence of the natural (non-vaccine-induced) antibody response to SARS-CoV-2 infection are not known in the pediatric population due to the high proportion of asymptomatic infection and the prioritization of testing for adults and people with disease serious at the beginning of the pandemic”.

However, they emphasized that “this information is important for the field as not all parents can or will choose to vaccinate their children.”

Sarah Messiah is one of the authors of the paper and professor at UTHealth, noting that “this is the first study in the Texas CARES survey that includes data from the three time points of the survey.”

“The findings are important because the information we collected from children infected with COVID-19 did not differ at all if a child was asymptomatic, the severity of symptoms, when they had the virus, if they were at a healthy weight or obesity, or by gender. They were the same for everyone,” said the expert.

For her, “studies in adults show that natural infection, plus vaccine-induced protection, is the best defense against COVID-19.” He added: “There has been a misunderstanding on the part of some parents who think that just because their child has had COVID-19, he is now protected and does not need to be vaccinated. While our study is encouraging because a certain amount of natural antibodies last at least six months in children, we do not yet know the absolute threshold of protection. The vaccine is a great tool to protect children.”

KEEP READING