Children who contract coronavirus develop natural circulating antibodies that last for at least seven months, according to a new study led by researchers at UTHealth Houston. The study was published today in the specialist magazine Pediatrics released.
The researchers examined data from 218 children aged 5 to 19 from a Texas state census. The survey began in October 2020 with the goal of determining antibody status in the adult and child population in Texas over time.
Volunteers who took part in the study provided the researchers with three separate blood samples. Samples were taken prior to the introduction of the vaccine and during the delta and omicron variants. So far, the researchers have completed three distinct phases of the study.
Absolute protection threshold not yet known
“This is the first study from the Texas CARES survey to include data from all three survey time points,” said Sarah Messiah, the study’s corresponding author and professor of epidemiology, human genetics and environmental sciences at the UTHealth School of Public Health on the Dallas campus. “These results are important because the information we collected from the children infected with Covid-19 did not differ according to whether a child was asymptomatic, the severity of the symptoms, when they got the virus, whether they were healthy was overweight or obese, nor by gender. It was the same for everyone.”
While 96 percent of children infected with Covid-19 still had antibodies up to seven months later, well over half (58 percent) of the sample was negative for infection-related antibodies at the third and final measurement. The results do not take into account the effects of vaccination protection.
The findings, Messiah said, are just a first step in understanding the impact of the virus on children. To date, 14 million children in the US have tested positive for the virus, she said.
“The adult literature tells us that natural infection and vaccination offer the best protection against Covid-19. Some parents feel that just because their child has contracted Covid-19, they are now protected and not need to be vaccinated and that is a misunderstanding. While our study is encouraging in that some level of natural antibodies persists in children for at least six months, we do not yet know the absolute protection threshold. We have a great tool at our disposal to Giving kids an extra layer of protection by getting vaccinated, so use it if your child is eligible,” Messiah said.