Comparison of febrile seizures in children with or without coronavirus disease-2019: A single-center observational study.

BACKGROUND: Febrile seizure (FS) is one of the most common neurological manifestations of coronavirus disease-2019 (COVID-19) in children. We compared the clinical characteristics of FS in patients with and without COVID-19 during the pandemic period. METHODS: This retrospective single-center study included patients aged 0-18 years who visited the pediatric emergency department (ED) with FS from January 1, 2022, to April 30, 2022. RESULTS: A total of 186 patients visited the pediatric ED with FS during the study period: 123 (66.1%) were positive for COVID-19 and 63 (33.9%) were negative. Patients with COVID-19 were predominantly male (70.7% vs. 50.8%, p = 0.007) and older (2.4 vs. 1.8 years, p = 0.005) than those without COVID-19. A higher proportion of patients with COVID-19 were of atypical age (age > 5 years or <6 months) than those without COVID-19 (26.8% vs. 9.5%, p = 0.006). This was especially true for those aged >5 years (22% vs. 4.8%, p = 0.003). Patients with COVID-19 had a higher probability of multiple episodes of convulsion within 24 h than those without COVID-19 (10.6% vs. 1.6%, p = 0.037). Among patients with COVID-19, males had a shorter fever-to-seizure duration than females (3 h vs. 6.5 h, p = 0.045). CONCLUSIONS: Patients with FS with COVID-19 tend to be predominantly male and have older age of onset than those without COVID-19. Because of the atypical age of onset and probability of multiple convulsion episodes, vigilance for FS is needed in patients with COVID-19, especially males.

The Association Between COVID-19 and Febrile Seizure: A Retrospective Case-Control Study.

BACKGROUND/OBJECTIVE: Throughout the pandemic, febrile seizures have resulted from infection secondary to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The objective of this study is to determine if there is an increased association between COVID-19 and febrile seizures as compared with other causes of febrile seizures. METHODS: This was a retrospective case control study. Data were collected from the National Institute of Health (NIH) supported National COVID Cohort Collaborative (N3C). Patients from 6 to 60 months who were tested for COVID-19 were included; cases were defined as COVID-19-positive patients whereas controls were defined as COVID-19-negative patients. Febrile seizures diagnosed within 48 hours of the COVID-19 test were considered to be associated with the test result. Patients were subjected to a stratified gender and date matching design followed by a logistic regression controlling for age and race. RESULTS: During the study period, 27,692 patients were included. Of those, 6923 patients were COVID-19-positive, among which 189 had febrile seizures (2.7%). After logistic regression, the likelihood of having febrile seizures concurrently with COVID-19 as compared with other causes was 0.96 ( P = 0.949; confidence interval, 0.81, 1.14). CONCLUSIONS: There were 2.7% of the patients with COVID-19 that were diagnosed with a febrile seizure. However, when subjected to a matched case control design with logistic regression controlling for confounding variables, there does not appear to be an increased risk of febrile seizures secondary to COVID-19 as compared with other causes.

The Impact of Omicron Wave on Pediatric Febrile Seizure.

BACKGROUND: The coronavirus disease 2019 (COVID-19) omicron (B.1.1.529) variant reduced the risk of severe disease compared with the original strain and other variants, but it appeared to be highly infectious, which resulted in an exponential increase in confirmed cases in South Korea. As the number of confirmed cases increased, so did the number of pediatric patients' hospitalization. This study aims to evaluate the frequency and clinical features of febrile seizure associated with the COVID-19 omicron variant in children. METHODS: We retrospectively reviewed the medical records of children aged under 18 years with febrile seizure who were tested for COVID-19 from February 2020 to April 2022 at Ajou University Hospital, South Korea. Based on the dominant variants, we divided the period into the pre-omicron (from February 2020 to December 2021) and omicron periods (from January 2022 to April 2022) and compared the clinical characteristics between the two. Also, we compared the clinical characteristics of febrile seizure between COVID-19 positive and negative group during the omicron period. RESULTS: Among the 308 children, 211 patients (9.2 patients/months) and 97 patients (24.3 patients/months) were grouped into pre-omicron and omicron periods, respectively. Compared with the pre-omicron period, patients in the omicron period showed significantly higher mean age (pre-omicron vs. omicron, 22.0 vs. 28.0 months; P = 0.004) and COVID-19 positive results (pre-omicron vs. omicron, 0.5% vs. 62.9%; P < 0.001). As the COVID-19 confirmed cases in the omicron period increased, the number of COVID-19 associated febrile seizure also increased. In the omicron period, 61 children were confirmed to be positive for COVID-19, and COVID-19 positive group showed statistically significant higher mean age (positive vs. negative, 33.0 vs. 23.0 months; P = 0.003) and peak body temperature than the negative group (positive vs. negative, 39.1°C vs. 38.6°C; P = 0.030). Despite the lack of significance, COVID-19 positive group showed longer seizure time, multiple seizure episodes, and higher prevalence of complex febrile seizure. CONCLUSION: The frequency of COVID-19 associated febrile seizure increased in the omicron periods. In addition, in this period, children with febrile seizure diagnosed with COVID-19 had a higher mean age and higher peak body temperature.

Background incidence rates of adverse events of special interest related to COVID-19 vaccines in Ontario, Canada, 2015 to 2020, to inform COVID-19 vaccine safety surveillance.

BACKGROUND: Background incidence rates are critical in pharmacovigilance to facilitate identification of vaccine safety signals. We estimated background incidence rates of 11 adverse events of special interest related to COVID-19 vaccines in Ontario, Canada. METHODS: We conducted a population-based retrospective observational study using linked health administrative databases for hospitalizations and emergency department visits among Ontario residents. We estimated incidence rates of Bell's palsy, idiopathic thrombocytopenia, febrile convulsions, acute disseminated encephalomyelitis, myocarditis, pericarditis, Kawasaki disease, Guillain-Barré syndrome, transverse myelitis, acute myocardial infarction, and anaphylaxis during five pre-pandemic years (2015-2019) and 2020. RESULTS: The average annual population was 14 million across all age groups with 51% female. The pre-pandemic mean annual rates per 100,000 population during 2015-2019 were 191 for acute myocardial infarction, 43.9 for idiopathic thrombocytopenia, 28.8 for anaphylaxis, 27.8 for Bell's palsy, 25.0 for febrile convulsions, 22.8 for acute disseminated encephalomyelitis, 11.3 for myocarditis/pericarditis, 8.7 for pericarditis, 2.9 for myocarditis, 2.0 for Kawasaki disease, 1.9 for Guillain-Barré syndrome, and 1.7 for transverse myelitis. Females had higher rates of acute disseminated encephalomyelitis, transverse myelitis and anaphylaxis while males had higher rates of myocarditis, pericarditis, and Guillain-Barré syndrome. Bell's palsy, acute disseminated encephalomyelitis, and Guillain-Barré syndrome increased with age. The mean rates of myocarditis and/or pericarditis increased with age up to 79 years; males had higher rates than females: from 12 to 59 years for myocarditis and ≥12 years for pericarditis. Febrile convulsions and Kawasaki disease were predominantly childhood diseases and generally decreased with age. CONCLUSIONS: Our estimated background rates will permit estimating numbers of expected events for these conditions and facilitate detection of potential safety signals following COVID-19 vaccination.

Evaluation of Febrile Seizure Diagnoses Associated With COVID-19.

BACKGROUND/OBJECTIVES: Infections with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may be associated with febrile seizures, but the overall frequency and outcomes are unknown. The objectives of this study are to (1) determine the frequency of pediatric subjects diagnosed with febrile seizures and COVID-19, (2) evaluate patient characteristics, and (3) describe the treatments (medications and need for invasive mechanical ventilation) applied. METHODS: This was a retrospective study utilizing TriNetX electronic health record data. We included subjects ranging from 0 to 5 years of age with a diagnosis of febrile seizures (R56.00, R56.01) and COVID-19 (U07.1). We extracted the following data: age, race, ethnicity, diagnostic codes, medications, laboratory results, and procedures. RESULTS: During this study period, 8854 pediatric subjects aged 0-5 years were diagnosed with COVID-19 among 34 health care organizations and 44 (0.5%) were also diagnosed with febrile seizures (simple, 30 [68.2%]; complex, 14 [31.8%]). The median age was 1.5 years (1, 2), there were no reported epilepsy diagnoses, and a proportion required hospitalization (11; 25.0%) and critical care services (4; 9.1%). CONCLUSIONS: COVID-19 infections in children can be associated with febrile seizures. In our study, 0.5% of COVID-19 subjects were diagnosed with febrile seizures and approximately 9% of subjects were reported to require critical care services. Febrile seizures, although serious, are not a commonly diagnosed neurologic manifestation of COVID-19.

Respiratory viruses and febrile response in children with febrile seizures: A cohort study and embedded case-control study.

OBJECTIVE: There are limited data on the pathogen-related and host-related factors in the pathogenesis of febrile seizures (FS). We designed a controlled study to compare the role of different respiratory viruses and febrile response in FS. METHODS: In a prospective cohort study of 1899 pediatric emergency room patients aged 6 months-6 years with a positive respiratory virus multiplex PCR, we identified 225 patients with FSs. We first compared the distribution of respiratory viruses in age-stratified patients with FSs with that in other patients. In an embedded case-control study, we compared the febrile response in patients with FSs with that in the controls matched for age, season and the same respiratory virus. RESULTS: The relative risk for FS was the highest for coronavirus OC43, 229E, and NL63 infections [RR: 3.2, 95 % confidence interval (CI): 1.4-7.2) and influenza A and B [RR: 2.5, 95 % CI: 1.4-4.7] as compared to those with other respiratory viral infections. The patients with FSs had a stronger febrile response of 39.2 °C (difference: 0.8 °C, 95 % CI: 0.5-1.2) later during hospitalization after acute care than the controls matched for the same respiratory virus. CONCLUSIONS: Influenza and coronaviruses caused relatively more FS-related emergency room visits than other respiratory viruses. Furthermore, the febrile response was stronger in the patients with FSs than in the controls matched for the same respiratory virus. The results suggest that the pathomechanism of FSs includes modifiable pathogen-related and host-related factors with possible potential in the prevention of FSs.