Risk of Invasive Meningococcal Disease in Preterm Infants

Abstract

Abstract Background Invasive meningococcal disease (IMD) is most common in the first year of life. We hypothesised that preterm infants may have a higher risk of IMD and more severe disease than term infants. We compared the incidence, demographics, clinical presentation and outcomes of IMD in preterm compared with term infants during the first five years after implementation of a national meningococcal group B vaccine (4CMenB) for infants in England. Methods The UK Health Security Agency (UKHSA) conducts enhanced national IMD surveillance with detailed follow-up of all confirmed cases in England. Infants aged <1 year (uncorrected for gestational age) with IMD confirmed between 01 September 2015 and 31 August 2020 were included. Results There were 393 infant IMD cases (incidence 12.4/100,000 live births). Among 363 (92.4%) infants with known gestational age, IMD incidence was higher in preterm (<37 weeks gestation) than term infants [18.3/100,000 vs 10.9/100,000; IRR 1.68 (95%CI 1.23-2.29), p=0.001]. IMD incidence was highest in those born at <32 weeks gestation (<32 weeks vs term: 32.9/100,000; IRR vs term 3.01; 95%CI, 1.73-5.24; p=<0.001). There were no differences in demographics, clinical presentation, rates of intensive care admission or case fatality, but preterm infants were more likely to have at least one reported sequela than term infants (14/39 [35.9%] vs 51/268 [19.0%]; p=0.02). Conclusions Preterm infants had a higher incidence of IMD than term infants and IMD incidence was highest in infants born at <32 weeks. Preterm infants also had a higher risk of IMD sequelae.