Related Experiment Video

Updated: Feb 7, 2026

Dynamic Monitoring of Seroconversion using a Multianalyte Immunobead Assay for Covid-19
08:48

Dynamic Monitoring of Seroconversion using a Multianalyte Immunobead Assay for Covid-19

Published on: February 16, 2022

3.5K

Febrile seizure risk following monovalent COVID-19 mRNA vaccination in US children aged 2-5 years

Steven A Anderson1, Elizabeth R Smith2, Zhiruo Wan2

  • 1US Food and Drug Administration, Silver Spring, MD, USA.

Vaccine
|February 5, 2026
PubMed

Insights

The monovalent mRNA-1273 COVID-19 vaccine showed a small increased risk of febrile seizures in children aged 2-5 years within 2 days of vaccination. The BNT162b2 vaccine did not show a statistically significant increase in febrile seizure risk.

Area of Science:

  • Pediatric infectious disease
  • Vaccine safety research
  • Epidemiology

Background:

  • The safety of COVID-19 vaccination in pediatric populations is crucial for public health.
  • Monovalent mRNA vaccines (mRNA-1273 and BNT162b2) were authorized for children aged 2-5 years.
  • Febrile seizures are a known potential adverse event in young children.

Purpose of the Study:

  • To assess the risk of febrile seizures following monovalent COVID-19 mRNA vaccination in children aged 2-5 years.
  • To compare the incidence of febrile seizures in the immediate post-vaccination period with a later control period.

Main Methods:

  • A self-controlled case series analysis was conducted using three commercial insurance databases.
  • The study compared febrile seizure risk in the 0-1 day interval post-vaccination to a 8-63 day control interval.
  • Conditional Poisson regression and meta-analyses were used to estimate incidence rate ratios (IRR) and confidence intervals (CI).

Main Results:

  • The mRNA-1273 vaccine was associated with a statistically significant increased incidence of febrile seizures (IRR: 2.52) in the 0-1 day period.
  • For the BNT162b2 vaccine, the IRR for febrile seizures was elevated but not statistically significant (IRR: 1.41).
  • The risk difference for mRNA-1273 was 3.22 per 100,000 doses, with a non-significant CI.

Conclusions:

  • A small, elevated incidence rate ratio of febrile seizures was observed within 0-1 days following mRNA-1273 vaccination in children aged 2-5 years.
  • The study did not find a statistically significant increase in febrile seizures following BNT162b2 vaccination in this age group.
  • Findings contribute to the ongoing monitoring of COVID-19 vaccine safety in pediatric populations.
Abstract

Keywords:
COVID-19 vaccineModernaPfizer-BioNTechSafety

More Related Videos

Detection of Polyfunctional T Cells in Children Vaccinated with Japanese Encephalitis Vaccine via the Flow Cytometry Technique09:37

Detection of Polyfunctional T Cells in Children Vaccinated with Japanese Encephalitis Vaccine via the Flow Cytometry Technique

Published on: September 23, 2022

2.3K
A High-Throughput Multiplexed Screening for Type 1 Diabetes, Celiac Diseases, and COVID-1906:46

A High-Throughput Multiplexed Screening for Type 1 Diabetes, Celiac Diseases, and COVID-19

Published on: July 5, 2022

3.3K

Related Concept Videos

Vaccinations01:51

Vaccinations

Overview
51.7K
Regulated mRNA Transport02:22

Regulated mRNA Transport

In eukaryotes, transcription and translation are compartmentalized; an mRNA is first synthesized in the nucleus and then selectively transported to the cytoplasm for protein synthesis. Before transport, a pre-mRNA undergoes several steps of post-transcriptional modifications including splicing, 5' capping, and the addition of a poly-adenine tail. Various proteins bind to the pre-mRNA during these modifications. The mRNA transport takes place with the help of multiple proteins playing...
7.0K
Nuclear Export of mRNA02:31

Nuclear Export of mRNA

Before mRNAs are exported to the cytoplasm, it is crucial to check each mRNA for structural and functional integrity. Eukaryotic cells use several different mechanisms, collectively known as mRNA surveillance, to look for irregularities in mRNAs. Irregular or aberrant mRNA are rapidly degraded by various enzymes. If a defective mRNA escapes the surveillance, it would be translated into a protein which would either be non-functional or not function properly. One of the primary irregularities in...
8.8K
mRNA Stability and Gene Expression02:51

mRNA Stability and Gene Expression

The structure and stability of mRNA molecules regulates gene expression, as mRNAs are a key step in the pathway from gene to protein. In eukaryotes, the half-life of mRNA varies from a few minutes up to several days. mRNA stability is essential in growth and development. The absence of the proteins regulating its stability, such as tristetraprolin in mice, can cause systemic issues, including bone marrow overgrowth, inflammation, and autoimmunity.
Cis-acting Elements involved in mRNA stability
6.7K
pre-mRNA Processing02:01

pre-mRNA Processing

In eukaryotic cells, transcripts made by RNA polymerase are modified and processed before exiting the nucleus. Unprocessed RNA is called precursor mRNA or pre-mRNA to distinguish it from mature mRNA.
Once about 20-40 ribonucleotides have been joined together by RNA polymerase, a group of enzymes adds a “cap” to the 5’ end of the growing transcript. In this process, a 5’ phosphate is replaced by modified guanosine that has a methyl group attached to it (7-Methyl...
57.6K
Nonsense-mediated mRNA Decay02:27

Nonsense-mediated mRNA Decay

The Upf proteins that carry out nonsense-mediated decay (NMD) are found in all eukaryotic organisms, including humans. Each protein has an individual role, but they need to work in collaboration. Upf1 is an ATP-dependent RNA helicase that unwinds the RNA helix. Because Upf1 can unwind any RNA, Upf2 and Upf3 are required to help Upf1 discriminate between nonsense and normal mRNAs.
Usually, Upf3 binds to an Exon Junction Complex (EJC) at mRNA splice sites. If a ribosome fully translates the mRNA,...
11.9K