BACKGROUNDS: The introduction of pneumococcal conjugate vaccines (PCVs) in pediatric national immunization programs (NIPs) have had a substantial global impact, however disease burden remains due to non-covered serotypes. In Sweden, where the 10-valent vaccine (PCV10) is part of the infant NIP, PCV10 covers only 7% of residual invasive pneumococcal disease (IPD) in children <5 years old. The 15- valent (PCV15) covers 35% of residual burden, while 20-valent (PCV20) covers 53% of residual burden. The objective of this study is to determine the public health impact of switching from PCV10 to PCV15 or PCV20 in Sweden’s infant NIP.
METHODS: A decision-analytic model was adapted to estimate IPD, hospital and non-hospital pneumonia, otitis media (OM) cases and deaths from switching to PCV15 or PCV20 in the 2024 NIP. The model utilized historical age-stratified real-world data to estimate future disease. Future IPD incidence, assuming a switch to higher-valent vaccines in 2024, is projected by calculating annual percent reductions in PCV13-10 type IPD incidence based on a systematic review. We assume that PCV20-13 type IPD incidence reductions will be equal to those reported for PCV13-10 serotypes. OM and pneumonia incidence are assumed to vary proportionately with IPD.
RESULTS: Compared to PCV15, switching to PCV20 is estimated to prevent 569 IPD cases, 571 OM cases, 2,734 hospitalized pneumonia cases and 103 non-hospitalized pneumonia cases, amounting to a total of 3,977 pneumococcal disease cases and 219 deaths over 5 years.
CONCLUSIONS/LEARNING POINTS: Replacing PCV10 with PCV20 is estimated to provide greater health impact compared to PCV15 in Sweden, given that the largest proportion of remaining pneumococcal disease burden is due to PCV20-unique serotypes. Thus, PCV20 has the potential to reduce disease further by protecting against additional non-covered serotypes and improve public health.
