Children who've had COVID-19 are not protected from Omicron - study

New research finds that children and adolescents showed a reduction in cross-neutralization against all of the variants, especially against Omicron.

 People pose with syringe with needle in front of displayed words "OMICRON SARS-COV-2" in this illustration taken, December 11, 2021 (photo credit: REUTERS/DADO RUVIC/ILLUSTRATION/FILE PHOTO)
People pose with syringe with needle in front of displayed words "OMICRON SARS-COV-2" in this illustration taken, December 11, 2021
(photo credit: REUTERS/DADO RUVIC/ILLUSTRATION/FILE PHOTO)

Children who have had COVID-19 or multisystem inflammatory syndrome (MIS-C) are not protected from the Omicron SARS-CoV-2 variant, but those who have been vaccinated are, a new study led by researchers at Boston Children's Hospital found.

How was the study conducted?

In the peer-reviewed study, published in the scientific journal Nature Communications on Friday, the researchers took blood samples from 62 children and adolescents who were hospitalized with COVID-19, another 65 who were hospitalized with MIS-C and 50 outpatients who had recovered from mild COVID-19. The samples were taken between 2020 and early 2021, prior to the appearance of the Omicron variant.

The researchers then introduced a pseudovirus derived from SARS-CoV-2 to the samples and determined how effectively antibodies in the samples destroyed the Alpha, Beta, Gamma, Delta and Omicron SARS-CoV-2 variants.

"Omicron is very different"

They found that children and adolescents showed a reduction in cross-neutralization against all of the variants, especially against Omicron.

“Omicron is very different from previous variants, with many mutations on the spike protein, and this work confirms that it is able to evade the antibody response. Unvaccinated children remain susceptible.”

Dr. Adrienne Randolph

“Omicron is very different from previous variants, with many mutations on the spike protein, and this work confirms that it is able to evade the antibody response,” according to Dr. Adrienne Randolph of Boston Children's Hospital, who led a predecessor study. “Unvaccinated children remain susceptible.”

 Test tubes labelled ''COVID-19 Omicron variant test positive'' are seen in this illustration picture taken January 15, 2022.  (credit: REUTERS/DADO RUVIC/ILLUSTRATION) Test tubes labelled ''COVID-19 Omicron variant test positive'' are seen in this illustration picture taken January 15, 2022. (credit: REUTERS/DADO RUVIC/ILLUSTRATION)

In comparison, children who had received two COVID-19 vaccine doses showed increased effectiveness against the variants.

Randolph said she hopes these findings will encourage parents to get their children vaccinated.