Importance The United States Food and Drug Administration noted a potential safety concern for seizure in children aged 2-5 years receiving the ancestral monovalent COVID-19 mRNA vaccines. Objective To evaluate febrile seizure risk following monovalent COVID-19 mRNA vaccination among children aged 2-5 years. Design, Setting, and Participants The primary analysis evaluated children who had a febrile seizure outcome in the 0-1 days following COVID-19 vaccination. A self-controlled case series analysis was performed in three commercial insurance databases to compare the risk of seizure in the risk interval (0-1 days) to a control interval (8-63 days). Exposure Receipt of dose 1 and/or dose 2 of monovalent COVID-19 mRNA vaccinations. Main Outcomes and Measures The primary outcome was febrile seizure (0-1 day risk interval). Analysis A conditional Poisson regression model was used to compare outcome rates in risk and control intervals and estimate incidence rate ratios (IRR) and 95% confidence intervals (CIs). Meta-analyses were used to pool results across databases. Results The primary meta-analysis found a statistically significant increased incidence of febrile seizure, in the 0-1 days following mRNA-1273 vaccination compared to the control interval (IRR: 2.52, 95% CI: 1.35 to 4.69, risk difference (RD)/100,000 doses = 3.22 (95%CI -0.31 to 6.75)). For the BNT162b2 vaccination, the IRR was elevated but not statistically significant (IRR: 1.41, 95%CI: 0.48 to 4.11, RD/100,000 doses = -0.25 (95%CI -2.75 to 2.24). Conclusions and Relevance Among children aged 2-5 years, the analysis showed a small elevated incidence rate ratio of febrile seizures in the 0-1 days following the mRNA-1273 vaccination. Based on the current body of scientific evidence, the safety profile of the monovalent mRNA vaccines remains favorable for use in young children.

中文翻译：

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美国 2-5 岁儿童接种祖先单价 COVID-19 mRNA 疫苗后热性惊厥风险评估

重要性 美国食品和药物管理局指出，接受祖传单价 COVID-19 mRNA 疫苗的 2-5 岁儿童可能会出现癫痫发作的潜在安全问题。目的 评估 2-5 岁儿童单价 COVID-19 mRNA 疫苗接种后热性惊厥的风险。设计、设置和参与者 主要分析评估了在接种 COVID-19 疫苗后 0-1 天内出现热性惊厥结果的儿童。在三个商业保险数据库中进行自我对照病例系列分析，比较风险区间（0-1 天）与对照区间（8-63 天）的癫痫发作风险。暴露 单价 COVID-19 mRNA 疫苗接种第 1 剂和/或第 2 剂的收据。主要结果和措施 主要结果是热性惊厥（0-1 天风险间隔）。分析 使用条件泊松回归模型来比较风险区间和控制区间的结果率，并估计发生率比 (IRR) 和 95% 置信区间 (CI)。荟萃分析用于汇集跨数据库的结果。结果 主要荟萃分析发现，与对照间隔相比，在 mRNA-1273 疫苗接种后 0-1 天内，热性惊厥的发生率显着增加（IRR：2.52，95% CI：1.35 至 4.69，风险差 (RD)） /100,000 剂 = 3.22（95%CI -0.31 至 6.75））。对于 BNT162b2 疫苗接种，IRR 有所升高，但无统计学意义（IRR：1.41，95%CI：0.48 至 4.11，RD/100,000 剂 = -0.25（95%CI -2.75 至 2.24）。 结论和相关性 在 2 岁儿童中-5年，分析显示接种mRNA-1273疫苗后0-1天内热性惊厥的发病率略有上升。根据目前的科学证据，单价mRNA疫苗的安全性仍然有利于使用在幼儿中。