Today a Kaiser Permanente Northern California study of children during the COVID-19 pandemic finds children too young to be vaccinated had the highest hospitalization rate, while adolescents had the highest rate of intensive care unit (ICU) admission. The findings are published in Influenza and Other Respiratory Viruses.
The study relied on health records from 1,107,799 children ages 0 to 18 who were members of Kaiser Permanente Northern California (KPNC). The pediatric patients were followed from March 1, 2020, through either chart-confirmed COVID-related hospitalization, disenrollment from KPNC, age 18 years, receipt of COVID-19 vaccine, or death.
In total, 423 children were hospitalized for COVID-19 during the study period, and infants 6 months and under—not eligible for vaccination—had the highest incidence of hospitalization. One hundred and three hospitalized children (24.3%) were less than 6 months of age, 40 (9.5%) were 6 to 11 months, 139 (32.9%) were 1 to 5 years old, 80 (18.9%) were 5 to 12 years, and 61 (14.4%) were 12 to 18 years of age.
Teens most likely to end up in ICU
Hospitalizations increased with each new COVID variant for unvaccinated children, peaking for children 6 months and under during Omicron, with a monthly incidence rate of 22.4 per 100,000 person-months.
Overall, 20.3% of hospitalized children were admitted to an ICU, but ICU admission disproportionately affected teens. Thirty-six percent of ICU admissions were among children 12 to 18 years. The vast majority of ICU patients (91.8%) had no comorbidities, the authors said.
Of all children requiring ICU care, 16% were diagnosed as having multisystem inflammatory syndrome in children (MIS-C), 4% required mechanical ventilation, 2% were diagnosed as having myocarditis, and 0.9% died.
"Among the 5–11-year-olds, 36% were diagnosed with MIS-C," the authors wrote. "These results suggest that while older children might be less likely to be hospitalized compared to younger children, when they do get hospitalized, they require a higher level of care."
Race, co-morbidities raise risk of hospitalization
The authors found Black and Hispanic children had a higher risk of hospitalization. Compared to White children, Black children had a risk ratio (RR) of 2.05 (95% confidence interval [CI], 1.33 to 3.16), and Hispanic children had a risk ratio of 1.82.
Sleep apnea, a compromised immune system, diabetes, cerebral palsy, and epilepsy were all linked to hospitalization. Overall, children with any comorbidities were at higher risk of hospitalization compared with those without a comorbidity (RR, 3.81; 95% CI, 2.94 to 4.95).
Vaccine uptake in the pediatric population has been suboptimal.
Although the study did not compare hospitalization rates among vaccinated and unvaccinated children, the authors said the study shows the importance of vaccination for kids.
"One of the most effective ways to prevent severe COVID-19 in the general population has been vaccination, which have been available for children as young as 6 months since June 2022 and for older children since May 2021," the authors said. "However, vaccine uptake in the pediatric population has been suboptimal."
