Health Care Provider Knowledge and Attitudes Regarding Adult Pneumococcal Conjugate Vaccine Recommendations

United States, September 28-October 10, 2022

Rebecca Kahn, PhD; Lindsay Zielinski, DO; Amber Gedlinske, MPH; Natoshia M. Askelson, PhD; Christine Petersen, DVM, PhD; Andrew M. Parker, PhD; Courtney A. Gidengil, MD; Alison P. Albert, MPH; Angela J. Jiles, MPH; Megan C. Lindley, MPH; Miwako Kobayashi, MD; Aaron M. Scherer, PhD


Morbidity and Mortality Weekly Report. 2023;72(36):979-984. 

In This Article

Abstract and Introduction


Despite the availability of effective vaccines against pneumococcal disease, pneumococcus is a common bacterial cause of pneumonia, causing approximately 100,000 hospitalizations among U.S. adults per year. In addition, approximately 30,000 invasive pneumococcal disease (IPD) cases and 3,000 IPD deaths occur among U.S. adults each year. Previous health care provider surveys identified gaps in provider knowledge about and understanding of the adult pneumococcal vaccine recommendations, and pneumococcal vaccine coverage remains suboptimal. To assess the feasibility and acceptability domains of the Advisory Committee on Immunization Practices (ACIP) Evidence to Recommendations (EtR) framework, a health care provider knowledge and attitudes survey was conducted during September 28–October 10, 2022, by the Healthcare and Public Perceptions of Immunizations Survey Collaborative before the October 2022 ACIP meeting. Among 751 provider respondents, two thirds agreed or strongly agreed with the policy option under consideration to expand the recommendations for the new 20-valent pneumococcal conjugate vaccine (PCV20) to adults who had only received the previously recommended 13-valent pneumococcal conjugate vaccine (PCV13). Gaps in providers' knowledge and perceived challenges to implementing recommendations were identified and were included in ACIP's EtR framework discussions in late October 2022 when ACIP updated the recommendations for PCV20 use in adults. Currently, use of PCV20 is recommended for certain adults who have previously received PCV13, in addition to those who have never received a pneumococcal conjugate vaccine. The survey findings indicate a need to increase provider awareness and implementation of pneumococcal vaccination recommendations and to provide tools to assist with patient-specific vaccination guidance. Resources available to address the challenges to implementing pneumococcal vaccination recommendations include the PneumoRecs VaxAdvisor mobile app and other CDC-developed tools, including summary documents and overviews of vaccination schedules and CDC's strategic framework to increase confidence in vaccines and reduce vaccine-preventable diseases, Vaccinate with Confidence.


Effective vaccines against pneumococcal disease have been available in the United States for decades. Beginning in 2012, adults at high risk for pneumococcal disease or for experiencing its associated complications (i.e., adults with immunocompromising conditions and, beginning in 2014, all adults aged ≥65 years) were recommended to receive a single dose of 13-valent pneumococcal conjugate vaccine (PCV13) (Wyeth Pharmaceuticals LLC, a subsidiary of Pfizer Inc.) in series with an indication-specific number of doses of 23-valent pneumococcal polysaccharide vaccine (PPSV23) (Merck Sharp and Dohme Corp.). However, pneumococcus continued to be a common bacterial cause of pneumonia, bacteremia, and meningitis, resulting in significant morbidity and mortality in the United States. Before the COVID-19 pandemic, approximately 100,000 hospitalized pneumococcal pneumonia cases occurred among U.S. adults per year,[1] with high all-cause mortality in older adults.[2] In addition, there were approximately 30,000 invasive pneumococcal disease (IPD) cases (e.g., meningitis or bacteremia) and 3,000 IPD deaths annually among U.S. adults.[1]

In October 2021, after licensure of two new pneumococcal conjugate vaccines (PCVs), 15-valent PCV (PCV15) (Merck Sharp and Dohme Corp.) and 20-valent PCV (PCV20) (Wyeth Pharmaceuticals LLC, a subsidiary of Pfizer Inc.) for use in U.S. adults, the Advisory Committee on Immunization Practices (ACIP) recommended PCV15 followed by 1 dose of PPSV23 or PCV20 alone for PCV-naïve adults aged ≥65 years or aged 19–64 years with certain health conditions or risk factors;[2] neither PCV15 nor PCV20 was recommended for adults who had previously received PCV13.§ PCVs are considered more immunogenic than PPSV23, and PCV20 provides the broadest pneumococcal serotype coverage among currently available PCVs, whereas PPSV23 contains additional serotypes that are not included in PCV20**.[3,4]

Previous surveys of health care providers identified gaps in their knowledge about and understanding of the adult pneumococcal vaccination recommendations.[5,6] In addition, coverage with either PCV15 or PCV20 remains low, particularly among adults aged 19–64 years who are at high risk for acquisition of or complications from pneumococcal disease (Immunization Services Division, National Center for Immunization and Respiratory Diseases, CDC, unpublished data, 2023). The ACIP Evidence to Recommendations (EtR) framework, which includes seven domains, was used to guide discussions on expanding recommendations to include the new PCV20 as an option for any adult at high risk who had received PCV13, regardless of whether they had completed their previously recommended vaccination series. To assess the feasibility and acceptability domains of the EtR framework in anticipation of these updates to the pneumococcal recommendations to include PCV20 as an option for adults at high risk who received PCV13, the Healthcare and Public Perceptions of Immunizations (HaPPI) Survey Collaborative conducted a knowledge and attitudes survey of family physicians, general internists, and pharmacists†† during September 28–October 10, 2022. The survey aimed to assess 1) behaviors and attitudes regarding pneumococcal vaccination recommendations, 2) knowledge about pneumococcal vaccination recommendations, and 3) attitudes toward expanding recommendations for use of PCV20 among adults who had previously received PCV13.

§These adults were recommended to receive PPSV23 according to earlier recommendations. In 2012, ACIP recommended PCV13 use in series with PPSV23 for adults with an immunocompromising condition, cerebrospinal fluid leak, or cochlear implant. In 2014, all adults aged ≥65 years were recommended to receive PCV13 in series with PPSV23. In 2019, the recommendation was updated and shared clinical decision-making was recommended regarding PCV13 use for adults aged ≥65 years without an immunocompromising condition, cerebrospinal leak, or cochlear implant.
Serotypes included in PPSV23: 1, 2, 3, 4, 5, 6B, 7F, 8, 9N, 9V, 10A, 11A, 12F, 14, 15B, 17F, 18C, 19F, 19A, 20, 22F, 23F, and 33F.
**Serotypes included in PCV20: 1, 3, 4, 5, 6A, 6B, 7F, 8, 9V, 10A, 11A, 12F, 14, 15B, 18C, 19A, 19F, 22F, 23F, and 33F.
††Pediatricians were also surveyed, but their responses were not analyzed.