The Present and Future of the Adult Pneumococcal Vaccine Program in the United States

Abstract

Streptococcus pneumoniae (pneumococcus) is a common cause of bacterial respiratory infections, such as pneumonia, sinusitis, and acute otitis media, and it also causes invasive diseases (i.e., infection in a normally sterile site), such as meningitis and bacteremia, leading to substantial morbidity and mortality. Before the coronavirus disease 2019 (Covid-19) pandemic, it is estimated that ≥100,000 pneumococcal pneumonia hospitalizations, ≥30,000 invasive pneumococcal disease cases, and 3000 invasive pneumocococcal disease deaths occurred among U.S. adults in a year.1 Resurgence of non-SARS-CoV-2 respiratory virus infections was reported in the United States in late 2022, and preliminary invasive pneumocococcal disease incidence in late 2022 exceeded the pre–Covid-19 baseline incidence in children and young adults (Centers for Disease Control and Prevention Active Bacterial Core surveillance, unpublished data). Effective pneumococcal vaccines are available and have been used in many countries. Although children have been the focus of pneumococcal vaccination programs globally,2 pneumococcal vaccines have also been recommended for adults in the United States for more than 40 years. The Advisory Committee on Immunization Practices updated their adult pneumococcal vaccine recommendations in October 2022, the fifth time since 2012 (Table 1), with the goal of increasing population-level protection against pneumococcal disease as well as reducing disparities in pneumococcal disease burden among those at increased risk.3 What have we learned from the U.S. adult pneumococcal vaccine program, what are the remaining gaps, and how can we address these gaps in considering future U.S. pneumococcal vaccine recommendations?