Introduction: Children with sickle cell disease (SCD) remain at higher risk for invasive infection with Streptococcus pneumoniae compared to the general pediatric population. Penicillin prophylaxis, pneumococcal conjugate (PCV), and polysaccharide vaccines (PPSV) have reduced the incidence of pneumococcal disease. Methods: A single institution cohort of children with SCD aged <19 years was reviewed over the 14-year period after PCV13 licensure (January 2010 – December 2023) to identify and characterize the clinical features and outcomes of S. pneumoniae bacteremia, including serotypes and antibiotic susceptibility. Results: The cohort included 4,356 children with SCD (24,076 person-years). Thirty-eight pneumococcal bacteremia cases were identified (32 HbSS, 5 HbSC, 1 HbSβ +-thalassemia), 21 (55%) in children age ≥5 years. The median time to culture positivity was 10.6 hours (range 3.4–20.2) from collection. Meningitis occurred in 4 (11%) and acute chest syndrome in 13 (34%). Serotype information was available for 36 (95%) isolates, which included 16 (44%) PPSV23 serotypes and 1 (2.6%) PCV13 serotype (serotype 3). Penicillin nonsusceptibility occurred in 12/31 (39%) at meningitis and 1/31 (3%) at non-meningitis breakpoints. Three (8%) deaths occurred (serotypes 12F, 23B, and 15B), all in children age ≥5 years, who had discontinued prophylactic penicillin. Long-term sequelae occurred in 5 (14%) surviving children, including hearing loss, limb amputation, motor and neurocognitive defects. Conclusion: Pneumococcal bacteremia continues to occur in children with SCD, with a risk of rapid progression to severe disease. Pneumococcal prevention strategies and urgent empiric treatment for fever remain important for children and adolescents of all ages with SCD.

Background: Influenza causes greater morbidity in pediatric patients with cancer or sickle cell disease (SCD). Limited data exists on influenza vaccination uptake for these populations in a low-vaccination state. Outpatient interventions improve vaccine uptake but isolated inpatient interventions remain unstudied. Procedure: We reviewed influenza vaccination of pediatric patients with cancer or SCD treated at Children’s Healthcare of Atlanta (CHOA) during three influenza seasons. An opt-out inpatient admission order set was implemented prior to the 2019-2020 influenza season. Vaccination status of patients that were admitted during an influenza season was compared pre- and post-intervention via Chi-squared analysis and multivariate logistic regression. Results: 1548 and 2549 patients with cancer and SCD (respectively) were eligible. The oncology (60%-62%) and SCD cohorts (61%-65%) had similar-to-higher vaccination uptake to the US (58-64%, p=0.01-0.79) and higher uptake compared to Georgia (51%-56%, p<0.01). There was no significant improvement in uptake after implementation of the inpatient intervention for admitted patients with cancer (40% vs 56%, p=0.05-0.88) or SCD (44% vs 56%, p=0.01). Multivariate logistic regression also found no significant increase in vaccine uptake (Hematologic Malignancy: 0.8 [0.73-0.98], Solid Tumor: 0.9 [0.80-1.90], CNS Tumor: 0.9 [0.71-1.14], SCD: 0.9 [0.85-0.99]). Conclusion: Pediatric patients with cancer and SCD have similar-to-greater influenza vaccination uptake compared to Georgia and the United States. An intervention focused on vaccinating hospitalized patients did not significantly improve the proportion of cancer or SCD patients who received influenza vaccine in each season. Future studies are needed to identify alternative approaches to improving vaccine uptake in these cohorts.