Risk of Invasive Meningococcal Disease in Children Aged <11 Years in the United States.

Background: Invasive meningococcal disease (IMD) is associated with high case-fatality rates and severe long-term sequelae. In the United States (US), IMD incidence rate (IR) is highest among infants aged <1 year, with most cases occurring in infants aged <6 months. This study estimated IMD incidence in commercially and Medicaid-insured infants, toddlers, and children aged <11 years. Methods: This retrospective claims analysis utilized real-world data (01 January 2005 to 31 December 2022) from the MarketScan® Commercial and Multi-State Medicaid Research Databases of infants (aged <1 year), toddlers (aged 1-4 years), and children (aged 5-10 years). IMD incidence, time at risk for IMD, IR, and IR ratio (IRR) were evaluated overall and by demographic/clinical characteristics. Results: Within the commercially and Medicaid-insured cohorts, 21 and 115 infants, 34 and 80 toddlers, and 36 and 37 children with IMD were identified, respectively. Overall IMD IRs in infants, toddlers, and children were 0.45, 0.17, and 0.11 per 100 000 person-years (PY; commercially insured) and 1.97, 0.45, and 0.18 per 100 000 PY (Medicaid-insured), respectively. Incidence rates were highest in infants aged <4 months (1.03 and 4.65 per 100 000 PY for infants aged 2 to <3 months [commercially insured] and 1 to <2 months [Medicaid-insured], respectively). Significantly elevated IRRs were observed among infants and children with specific demographic and clinical characteristics, including residence in rural counties, immunocompromised status, and complement component deficiency. Conclusions: IMD incidence is low in the United States, but varies by age, insurance type, and demographic/clinical characteristics. Timely preventative interventions, such as early vaccination, may reduce the incidence, risk, and associated burden of IMD.