Durability of Original Monovalent mRNA Vaccine Effectiveness Against COVID-19 Omicron-Associated Hospitalization in Children and Adolescents - United States, 2021-2023.

Pediatric COVID-19 vaccination is effective in preventing COVID-19-related hospitalization, but duration of protection of the original monovalent vaccine during SARS-CoV-2 Omicron predominance merits evaluation, particularly given low coverage with updated COVID-19 vaccines. During December 19, 2021-October 29, 2023, the Overcoming COVID-19 Network evaluated vaccine effectiveness (VE) of ≥2 original monovalent COVID-19 mRNA vaccine doses against COVID-19-related hospitalization and critical illness among U.S. children and adolescents aged 5-18 years, using a case-control design. Too few children and adolescents received bivalent or updated monovalent vaccines to separately evaluate their effectiveness. Most case-patients (persons with a positive SARS-CoV-2 test result) were unvaccinated, despite the high frequency of reported underlying conditions associated with severe COVID-19. VE of the original monovalent vaccine against COVID-19-related hospitalizations was 52% (95% CI = 33%-66%) when the most recent dose was administered <120 days before hospitalization and 19% (95% CI = 2%-32%) if the interval was 120-364 days. VE of the original monovalent vaccine against COVID-19-related hospitalization was 31% (95% CI = 18%-43%) if the last dose was received any time within the previous year. VE against critical COVID-19-related illness, defined as receipt of noninvasive or invasive mechanical ventilation, vasoactive infusions, extracorporeal membrane oxygenation, and illness resulting in death, was 57% (95% CI = 21%-76%) when the most recent dose was received <120 days before hospitalization, 25% (95% CI = -9% to 49%) if it was received 120-364 days before hospitalization, and 38% (95% CI = 15%-55%) if the last dose was received any time within the previous year. VE was similar after excluding children and adolescents with documented immunocompromising conditions. Because of the low frequency of children who received updated COVID-19 vaccines and waning effectiveness of original monovalent doses, these data support CDC recommendations that all children and adolescents receive updated COVID-19 vaccines to protect against severe COVID-19.

Optic nerve sheath diameter does not correlate with intracranial pressure in pediatric neurocritical care patients.

PURPOSE: Intracranial pressure (ICP) > 20 mmHg is associated with worse outcomes in children. The gold standard for monitoring ICP is invasive, has complications such as bleeding and infection, and may not be available in resource limited areas. Ultrasound of the optic nerve sheath diameter (ONSD) has been studied as a noninvasive way to evaluate for elevated ICP in adults. Its utility in pediatrics remains unclear. METHODS: A prospective study was performed in a pediatric intensive care unit in children ≤ 18 years old. ONSD ultrasound was performed using a 13-6 MHz linear probe with the patient's invasively measured ICP simultaneously recorded. Linear mixed effects models were used to evaluate the association between ONSD and ICP. RESULTS: One hundred thirty-six measurements were obtained from 16 patients. ONSD was not significantly associated with ICP (p = 0.51). A ROC curve assessing ONSD to determine elevated ICP > 20 mmHg had an area under the curve of 0.52 (95%CI = 0.32-0.72). There was no difference in measurements obtained between the left and right ONSD at the same time (p = 0.82). CONCLUSIONS: In conclusion, this study demonstrated no association between ONSD measurement and invasively monitored ICP in critically ill children.