What’s New in Pneumococcal Vaccines

Column Author: Christine Symes, MSN, APRN, CPNP | Infectious Diseases

Column Editor: Angela Myers, MD, MPH | Pediatric Infectious Diseases; Division Director, Infectious Diseases; Medical Director, Center for Wellbeing; Professor of Pediatrics, University of Missouri-Kansas City School of Medicine; Clinical Assistant Professor of Pediatrics, University of Kansas School of Medicine

Streptococcus pneumoniae is a leading cause of community-acquired pneumonia and bacterial meningitis, as well as a common pathogen in otitis media in children. Pneumococcal 13-valent conjugate vaccine (PCV 13) was approved by the Food and Drug Administration (FDA) in February 2010 and replaced the 7-valent vaccine, which had been in use since 2000. It is indicated for active immunization against invasive pneumococcal disease. PCV 13 contains purified capsular polysaccharides of 13 pneumococcal serotypes (1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F and 23F) conjugated to a carrier protein to optimize antibody response, especially in infants and young children. PCV 13 is recommended to be given at 2, 4 and 6 months of age (but the first dose can be given as early as 6 weeks of age) followed by a final dose at age 12-15 months in the routine immunization schedule recommended by the Advisory Committee on Immunization Practices (ACIP) for children. There are alternate dosing recommendations for catch-up vaccination and for certain high-risk individuals. 

But wait, now there is an additional pneumococcal vaccine that can be used as an alternative. PCV 15 was recommended for use as an option for pneumococcal conjugate vaccination in children <19 years of age by the ACIP on June 22, 2022. Use of PCV 15 as an alternative to PCV 13 is anticipated to further reduce pneumococcal disease incidence in children and adolescents by inducing immunity against two additional strains of S. pneumoniae. PCV 15 is purified capsular polysaccharides of 15 serotypes of S. pneumoniae (including the PCV 13 serotypes plus 22F and 33F) that are individually conjugated to a nontoxic variant of diphtheria toxin.¹ PCV 15 can be used interchangeably with PCV 13 and is recommended for all children aged 6 weeks-17 years and in others with certain risk factors. PCV 15 is recommended to be given on the same dosing schedule as PCV 13.  

Safety of the vaccine was assessed in seven randomized controlled trials in children aged 6 weeks-17 years and included infants born prematurely. In these studies, four of 4,540 children (0.088%) who received PCV 15 developed serious adverse events that were deemed vaccine-related, compared with one of 2,655 (0.038%) who received PCV 13. The most reported adverse events after any PCV dose included irritability (75.1% in the PCV 15 group versus 72.7% in the PCV 13 group), somnolence (56.7% versus 59.3%), injection site pain (45.1% versus 43.5%), and decreased appetite (39.1% versus 36.0%).²  

A PCV 20 vaccine is also now in use and approved for adults ≥65 or those 19-64 with certain underlying health conditions. This vaccine is not for use in children.³ 

Pneumococcal vaccination has been extremely successful in reducing the burden of disease. Invasive pneumococcal disease dramatically declined in both children and adults following the introduction of pneumococcal conjugate vaccines in the United States in 2000. From 1998 to 2019, invasive pneumococcal disease rates among children <5 years of age decreased by 93%. Invasive pneumococcal disease caused by the 13 serotypes covered by PCV 13 decreased by 98% in children less than 5 years of age during this same time period.⁴  

The COVID-19 pandemic and related disruptions in health care have resulted in a decline in overall vaccination rates in the United States. The rate of 5-month-old infants current per ACIP recommendations fell from the May 2019 rate of 67.9% to 49.7% in May 2020.⁵ It remains critical to recommend childhood vaccinations at every health care encounter. In particular, the PCV 15 vaccine offers the potential to further reduce pneumococcal disease incidence in children and adolescents by inducing immunity against two additional strains. 

References: 

1. About pneumococcal vaccines. Centers for Disease Control and Prevention. Accessed January 10, 2023. https://www.cdc.gov/vaccines/vpd/pneumo/hcp/about-vaccine.html 
2. Kobayashi M, Farrar JL, Gierke R, et al. Use of 15-valent pneumococcal conjugate vaccine among U.S. children: updated recommendations of the Advisory Committee on Immunization Practices — United States, 2022. MMWR Morb Mortal Wkly Rep. 2022;71:1174-1181. doi:10.15585/mmwr.mm7137a3  
3. Surveillance and reporting. Centers for Disease Control and Prevention. Accessed January 10, 2023. https://www.cdc.gov/pneumococcal/surveillance.html 
4. Kobayashi M, Farrar JL, Gierke R, et al. Use of 15-valent pneumococcal conjugate vaccine and 20-valent pneumococcal conjugate vaccine among U.S. adults: updated recommendations of the Advisory Committee on Immunization Practices — United States, 2022. MMWR Morb Mortal Wkly Rep. 2022;71:109-117. doi:10.15585/mmwr.mm7104a1 
5. Bramer CA, Kimmins LM, Swanson R, et al. Decline in child vaccination coverage during the COVID-19 pandemic — Michigan Care Improvement Registry, May 2016–May 2020. MMWR Morb Mortal Wkly Rep. 2020;69:630-631. doi:10.15585/mmwr.mm6920e1