Obesity and Metabolic Dysregulation in Children Provide Protective Influenza Vaccine Responses.

The most effective intervention for influenza prevention is vaccination. However, there are conflicting data on influenza vaccine antibody responses in obese children. Cardio-metabolic parameters such as waist circumference, cholesterol, insulin sensitivity, and blood pressure are used to subdivide individuals with overweight or obese BMI into 'healthy' (MHOO) or 'unhealthy' (MUOO) metabolic phenotypes. The ever-evolving metabolic phenotypes in children may be elucidated by using vaccine stimulation to characterize cytokine responses. We conducted a prospective cohort study evaluating influenza vaccine responses in children. Participants were identified as either normal-weight children (NWC) or overweight/obese using BMI. Children with obesity were then characterized using metabolic health metrics. These metrics consisted of changes in serum cytokine and chemokine concentrations measured via multiplex assay at baseline and repeated at one month following vaccination. Changes in NWC, MHOO and MUOO were compared using Chi-square/Fisher's exact test for antibody responses and Kruskal-Wallis test for cytokines. Differences in influenza antibody responses in normal, MHOO and MUOO children were statistically indistinguishable. IL-13 was decreased in MUOO children compared to NWC and MHOO children (p = 0.04). IL-10 approached a statistically significant decrease in MUOO compared to MHOO and NWC (p = 0.07). Influenza vaccination does not provoke different responses in NCW, MHOO, or MUOO children, suggesting that obesity, whether metabolically healthy or unhealthy, does not alter the efficacy of vaccination. IL-13 levels in MUO children were significantly different from levels in normal and MHOO children, indicating that the metabolically unhealthy phenotypes may be associated with an altered inflammatory response. A larger sample size with greater numbers of metabolically unhealthy children may lend more insight into the relationship of chronic inflammation secondary to obesity with vaccine immunity.

Early Experience of COVID-19 in a US Children's Hospital.

OBJECTIVES: We aim to describe the demographics, clinical presentation, hospital course, and severity of pediatric inpatients with coronavirus disease 2019 (COVID-19), with an emphasis on healthy, immunocompromised, and chronically ill children. METHODS: We conducted a single-center retrospective cohort study of hospitalized children aged younger than 22 years with COVID-19 infection at Steven and Alexandra Cohen Children's Medical Center at Northwell Health. Cases were identified from patients with fever and/or respiratory symptoms who underwent a nucleic acid amplification-based test for severe acute respiratory syndrome coronavirus 2. RESULTS: Sixty-five patients were identified. The median age was 10.3 years (interquartile range, 1.4 months to 16.3 years), with 48% of patients older than 12 years and 29% of patients younger than 60 days of age. Fever was present in 86% of patients, lower respiratory symptoms or signs in 60%, and gastrointestinal symptoms in 62%. Thirty-five percent of patients required ICU care. The white blood cell count was elevated in severe disease (P = .0027), as was the C-reactive protein level (P = .0192), compared with mild and moderate disease. Respiratory support was required in 34% of patients. Severity was lowest in infants younger than 60 days of age and highest in chronically ill children; 79% of immunocompromised children had mild disease. One death was reported. CONCLUSIONS: Among children who are hospitalized for COVID-19, most are younger than 60 days or older than 12 years of age. Children may have severe infection requiring intensive care support. The clinical course of immunocompromised patients was not more severe than that of other children. Elevated white blood cell count and C-reactive protein level are associated with greater illness severity.