Adult Pneumococcal Vaccine Rules Confused Many Providers: A 2022 Survey

In brief

• Pneumococcal disease remains a major cause of illness in U.S. adults despite effective vaccines.
• A survey of providers before the October 2022 meeting of the Advisory Committee on Immunization Practices (ACIP) found gaps in knowledge and trouble putting the recommendations into practice.
• Most respondents agreed with expanding the 20-valent pneumococcal conjugate vaccine (PCV20) to high-risk adults who had received only the 13-valent vaccine (PCV13).
• Tools to help include CDC's PneumoRecs VaxAdvisor app, overviews of vaccination schedules, and CDC's Vaccinate with Confidence framework.

Background

Pneumococcus is a common bacterial cause of pneumonia, bacteremia and meningitis. Before the COVID-19 pandemic, U.S. adults had about 100,000 hospitalizations for pneumococcal pneumonia a year — with high death rates from all causes among older adults — plus about 30,000 cases of invasive pneumococcal disease (IPD) and 3,000 IPD deaths.

From 2012, adults at high risk — those with immunocompromising conditions and, from 2014, everyone 65 and older — were advised to get one dose of PCV13 followed by doses of the 23-valent polysaccharide vaccine (PPSV23). In October 2021, after two new conjugate vaccines were licensed, ACIP recommended either PCV15 followed by one dose of PPSV23, or PCV20 alone, for adults 65 and older, and for adults 19–64 with certain conditions or risk factors, who had never had a conjugate vaccine. Neither was recommended for people who had already had PCV13. Conjugate vaccines are considered to prompt a stronger immune response than PPSV23, and PCV20 covers the most pneumococcal serotypes of the conjugate vaccines, though PPSV23 includes some serotypes PCV20 lacks.

Earlier surveys had found providers unclear on the adult recommendations, and coverage with PCV15 or PCV20 was low, especially among high-risk adults aged 19–64. ACIP's Evidence to Recommendations (EtR) framework, with seven domains, guided its discussion of offering PCV20 to any high-risk adult who had received PCV13. To inform two of those domains — feasibility and acceptability — the Healthcare and Public Perceptions of Immunizations (HaPPI) Survey Collaborative of CDC, the University of Iowa and the RAND Corporation surveyed providers from September 28 to October 10, 2022.

The survey

It drew on an online panel of 2 million U.S. health care providers. Respondents had to spend at least half their practice time in outpatient primary care and give vaccines where they worked. It was opt-in, with 5-point agree–disagree scales, open answers, and multiple-choice and true-or-false knowledge questions. Of 829 eligible family physicians, general internists and pharmacists who consented, 757 (91%) completed it. (Pediatricians were also surveyed but not analyzed.)

What providers said

The recommendations are hard to follow. Of 751, 283 (38%) disagreed that they were "easy to follow." In open answers:

Patients' vaccine hesitancy was a reason for not recommending conjugate vaccines for 63 (25%) family physicians, 56 (22%) internists and 40 (16%) pharmacists.

About half were not familiar with the 2021 recommendations. 372 (50%) of 750 wrongly said adults 65 and older who had had PCV13 should later get PCV20. For a 65-year-old who had never had a conjugate vaccine, 264 (35%) correctly chose PCV15 followed by PPSV23 and 319 (43%) correctly chose PCV20 alone. 403 (53%) of the 757 had never used CDC's PneumoRecs VaxAdvisor app.

Figure 1. Providers' answers on which pneumococcal vaccines a conjugate-vaccine–naïve adult aged 65 or older should receive. CDC, MMWR.

Most supported expanding PCV20 after PCV13 alone. Two thirds agreed with offering PCV20 to adults who had received only PCV13 — 531 (71%) for adults 19–64 with an immunocompromising condition, and 478 (64%) for everyone 65 and older. Fewer than half agreed with extending it to adults who had received both PCV13 and PPSV23: 353 (47%) for immunocompromised adults and 286 (38%) for everyone 65 and older.

Figure 2. Percentage of providers who agreed with expanding PCV20 use, by high-risk group and provider type. CDC, MMWR.

What ACIP did

These findings were part of ACIP's discussion in late October 2022. It updated its recommendations so that high-risk adults who had received PCV13 but not all their PPSV23 doses could get one dose of PCV20 instead, and recommended shared clinical decision-making on PCV20 for adults 65 and older who had completed both PCV13 and PPSV23.

Why it matters

Providers value the vaccines, but many find the nuances — which vary with a patient's vaccination history and conditions — hard to interpret and apply. That may help explain low uptake: as of December 2022, only 4.4% of Medicare beneficiaries 65 and older had received PCV15 or PCV20, and 7.1% of those aged 65–69, the least likely to have had PCV13. Coverage is also low among adults with conditions that raise their risk, and varies by race and ethnicity and geography.

The authors call for raising provider awareness of the October 2022 recommendations and for tools that give patient-specific guidance — the PneumoRecs VaxAdvisor app, schedule summaries, point-of-care decision tools, continuing education and conference sessions, and Vaccinate with Confidence, CDC's framework for protecting communities, empowering families and stopping misinformation. As more vaccines join the adult schedule, CDC needs a consistent way of communicating new recommendations.

Limitations: the sample was a convenience sample, though evenly spread across provider types and geographically diverse; and the knowledge questions did not account for which vaccines each clinic stocked, which may have skewed the answers of providers whose clinics did not carry PCV20.

Sources

Based on Rebecca Kahn, Lindsay Zielinski, Amber Gedlinske, Natoshia M. Askelson, Christine Petersen, Andrew M. Parker, Courtney A. Gidengil, Alison P. Albert, Angela J. Jiles, Megan C. Lindley, Miwako Kobayashi and Aaron M. Scherer, "Health Care Provider Knowledge and Attitudes Regarding Adult Pneumococcal Conjugate Vaccine Recommendations — United States, September 28–October 10, 2022," MMWR Morbidity and Mortality Weekly Report, volume 72, Centers for Disease Control and Prevention; a work of the United States government in the public domain. The serotype lists and references are left out.