Invasive Pneumococcal Disease in Infants Aged 0-60 Days in the United States in the 13-Valent Pneumococcal Conjugate Vaccine Era

Area of Science:

• Pediatrics
• Infectious Diseases
• Vaccinology

Background:

• Invasive pneumococcal disease (IPD) remains a significant threat to infant health.
• The 13-valent pneumococcal conjugate vaccine (PCV13) was introduced to reduce the burden of IPD.
• Understanding the serotype distribution and vaccine effectiveness is crucial for public health strategies.

Purpose of the Study:

• To evaluate the impact of PCV13 introduction on IPD incidence and serotype distribution in young infants.
• To assess the evidence of indirect protection conferred by PCV13 in infants aged 0-60 days.
• To determine the proportion of IPD cases caused by PCV13 serotypes post-vaccine introduction.

Main Methods:

• Retrospective cohort study of 53 infants diagnosed with IPD.
• Data collected from 8 children's hospitals in the United States between 2005 and 2015.
• Analysis of IPD cases before and after the introduction of PCV13, focusing on serotype-specific incidence.

Main Results:

• A decrease of approximately 30% in IPD caused by PCV13 serotypes was observed post-vaccine introduction.
• This decrease suggests some level of indirect protection from PCV13 vaccination in the infant population.
• Despite the reduction, approximately 60% of all IPD cases in infants were still attributed to PCV13 serotypes.

Conclusions:

• PCV13 introduction has had a partial impact on reducing IPD caused by targeted serotypes in young infants.
• Evidence of indirect protection exists, but a substantial burden of IPD remains due to PCV13 serotypes.
• Continued surveillance and potential updates to vaccination strategies are warranted to further combat infant IPD.