Antibodies from a COVID-19 infection linger in most children for up to seven months, even if they had no symptoms, a new study finds.

To come to that reassuring conclusion, researchers analyzed data from 218 children in Texas, ages 5 to 19, who were enrolled in an ongoing survey launched in October 2020 to track COVID-19 antibody status in children and adults over time.

Blood samples were collected from participants before vaccines became available and during the surges of the delta and omicron variants.

While 96% of children who were infected with COVID-19 still had antibodies at least six months later, 58% did not have infection-triggered antibodies at their third and final blood test.

The report, published March 18 in the journal Pediatrics, did not assess the impact of vaccination.

"This is the first study from the Texas CARES survey that includes data from all three time points in the survey," said corresponding author Sarah Messiah. She is a professor of epidemiology, human genetics and environmental sciences at the University of Texas Health Science Center at Houston.

"These findings are important because the information we collected from children infected with COVID-19 didn't differ at all by whether a child was asymptomatic, severity of symptoms, when they had the virus, were at a healthy weight or had obesity, or by gender," she added in a university news release. "It was the same for everyone."

To date, 14 million children in the United States have tested positive for the virus, and these findings help improve understanding of how it affects children, according to Messiah.

"Adult literature shows us that natural infection, plus the vaccine-induced protection, gives you the best defense against COVID-19. There has been a misunderstanding from some parents who think just because their child has had COVID-19, they are now protected and don't need to get the vaccine," Messiah said.

"While our study is encouraging in that some amount [of] natural antibodies last at least six months in children, we still don't know the absolute protection threshold," she added. "We have a great tool available to give children additional protection by getting their vaccine, so if your child is eligible, take advantage of it."