By Susan Hollenberg BSc MD MCFP (biography, no disclosures) Clinical Assistant Professor, Family Medicine, UBC; Education Lead, UBC Health Clinic
What I did before
In my office, we are fielding increasing patient questions about pneumococcal vaccines as COVID pandemic concerns are focussing attention on vaccine-preventable respiratory illness. People are seeing glossy advertising for pneumococcal conjugate vaccine (PCV-13), and pharmacists are mentioning that adults should consider this product. I have routinely offered pneumococcal vaccine to my patients as they turned 65. Since 1997 in BC, polysaccharide pneumococcal vaccine became a public health-funded vaccine on a one-time basis for all healthy seniors. Pneumococcal vaccine became increasingly indicated for special populations, and I added other medical conditions to my immunization offer. When seniors came in for a flu shot it became a reminder to ask if they had received ‘pneumonia vaccine’. In the early 2000’s we began using other types of pneumococcal vaccine in infants, and I struggled to understand the differences between products. I was left confused as to the evidence base for these vaccines and how to frame a discussion with patients.
There are two distinct types of pneumococcal vaccine available for adults in Canada. Polysaccharide vaccines are inactivated vaccines composed of long chains of sugar antigens that make up the surface capsule of bacteria. They induce mainly IgM response and low levels of IgG, providing 5-10 years of protection. Booster doses can induce a paradoxical hypo-responsiveness and are not generally recommended. Polysaccharide pneumococcal vaccine contains 23 serotypes (PPV-23). Conjugate vaccines are created by attaching a polysaccharide molecule to a carrier protein (in this case diphtheria toxoid), which increases the immunogenicity of the antigen. This is a T- and B- cell-dependent process and induces immunologic memory. Pneumococcal conjugate vaccine (PCV-13) contains 13 serotypes, 12 of which are included in PPV-23 (2). If primed by a conjugate vaccine, the subsequent immunologic response to a polysaccharide vaccine is much greater.
Disease caused by Streptococcus pneumoniae is common globally and continues to cause significant morbidity and mortality. WHO estimates that there are almost 500,000 deaths annually in children under the age of 5 due to pneumococcal illness (2). There are at least 25,000 pneumococcal-related adult deaths annually in the US (11). In 2019 in BC, BCCDC reported 533 cases of invasive pneumococcal disease (IPD), with increasing incidence reported from Vancouver Island and Northern Health Authorities (10). IPD occurs when S.pneumoniae invades the bloodstream or CNS, and is most common in the very young, elderly, and immune-compromised individuals. In children, it often presents as bacteremia or meningitis. In adults, bacteremic pneumonia is the typical presentation, often as a complication of influenza or other lower respiratory illness. Mortality rate is 5-7% and higher in the elderly. S.pneumoniae colonizes the nasopharynx, and spreads by droplet transmission, respiratory secretions, or direct oral contact. Risk factors that increase adult illness caused by pneumococcus include underlying medical conditions, immune compromise, and long term care residence. Populations such as smokers, the homeless, illicit drug users, and people with alcoholism are especially susceptible. Given these grim statistics it was puzzling to learn that in Canada, in 2014, the coverage of adults 65 and older with PPV-23 vaccine was only 36.5%! In addition, considering the fact that increasing respiratory and blood isolates of S.pneumoniae are penicillin-resistant, emphasis placed on preventive strategies, including the delivery of effective pneumococcal immunizations, should be paramount. (1) (2) (5) (6)
What changed my practice
In 2019, the US ACIP (Advisory Committee on Immunization Practice ) published a position paper on pneumococcal vaccines, seeking to address considerations for PCV-13 use among adults >65 yr. (5) (6) This has been pivotal in my current understanding and discussion of these vaccines, as the framework closely parallels the experience of use of pneumococcal vaccine products in Canada.
A 7-valent conjugate pneumonia vaccine was introduced into routine US childhood programs in 2000. From 2000-2010, there was a drastic decline in pediatric otitis media, bacteremia and meningitis, along with reductions in all-cause pneumonia in adult populations. The PCV-13 vaccine replaced PCV-7 in childhood programs in 2010. Over the next 4 years, Community-Acquired Pneumonia (CAP) decreased by 35% in adults ages 65-74, and by 20% in adults 75 yr. The conjugate pneumococcal vaccine was not approved for use in adults until 2014. That year, ACIP recommended PCV -13 for all seniors followed by PPV-23 8 weeks later. By 2019, 47% of US adults had taken PCV-13. However, between 2014-2019 there was no further population level impact on CAP or IPD.
The greatest impact of the use of PCV-13 in adults is likely through the indirect effect from pediatric use. The beneficial effects of pediatric pneumococcal vaccination are observed in adults across all ages, medical conditions, ethnicity, and socioeconomic groups. Non PCV-13 serotypes currently make up the majority of the disease burden of community-acquired pneumonia. Pneumonia caused by the PCV-13 serotypes in 2014-2016 was estimated to be just 4% of all-cause pneumonia. These findings resulted in ACIP amending recommendations for the use of PCV-13 and pneu-23 in adults in June 2019. The summary statement recommended that all adults 65yr should receive a single dose of PPV-23, as it covers more strains. PCV-13 vaccine is no longer recommended for healthy adults 65 on a population-wide basis. Adults with certain medical conditions and immune compromise should consider receiving PCV-13 followed by PPV-23 8 weeks later.
It can be useful to reframe vaccine information with the concept of number needed to vaccinate (NNV) which combines the effectiveness of a vaccine with the incidence of a disease in a population for prevention of an outcome (7). For PCV-13 in healthy adults, the annual NNV is 26,000 adults per year to prevent one case of invasive pneumococcal disease, 3000-14,000 to prevent one case of inpatient pneumonia, and 2600 to prevent one case outpatient pneumonia (5).
What I do now
Incorporating this evidence to inform pneumococcal vaccination practice in adults in Canada, NACI (1) (2) recommends giving PPV- 23 on a population-wide basis in adults as it is 50-80% effective in prevention of IPD amongst the elderly and high-risk groups. The strains implicated in the majority of cases of IPD in adults in Canada are contained in PPV-23 and not in PCV-13. In Canada, PCV-7 was incorporated into routine childhood immunization programs in 2003 and PCV-13 replaced it in 2010 (12). PCV-13 has estimated effectiveness of 86-97% in children <5yr(2). Polysaccharide vaccine is not routinely used in infants or children as it is much less immunogenic than conjugate products in these age groups.
In BC there is public funding for a one-time dose of PPV-23 for all healthy seniors at age 65. (3) (4) For high-risk individuals the recommendation is to give 1 dose at the time of diagnosis. Consider the use of PCV-13 on an individual basis. High-risk conditions include anatomic or functional asplenia, Sickle Cell Disease, immunosuppression related to disease or drug therapy, congenital immunodeficiency states, chronic heart, lung, liver or kidney disease, solid organ or HSCT recipient, diabetes, alcoholism, Cystic Fibrosis, chronic CSF leak, cochlear implant, homelessness, illicit drug use, chronic neurological conditions that impair clearance of oral secretions and residents of extended or intermediate care facilities. (BC Centre for Disease Control. Pneumococcal Polysaccharide Vaccine. Vancouver, BC: BC Centre for Disease Control; October 2018. view)
There is high-quality evidence for the use of PCV-13 vaccine in people with HIV and Hematopoetic Stem Cell transplant recipients and it is funded in BC for these adult groups. For other persons, PCV-13 is a private pay vaccine, available through pharmacies and travel clinics. For the highest risk individuals, adults 19+ with immune-compromising conditions, the recommendation is to give PCV-13 followed by PPV-23 after 8 weeks. Once only revaccination for PPV-23 should be offered 5 years after initial immunization. (BC Centre for Disease Control. Pneumococcal Conjugate Vaccine. Vancouver, BC: BC Centre for Disease Control; August 2018. view)
Reference Table of Adult Pneumococcal Vaccine recommendations from Canadian Immunization Guide (2, view)
|Table 4: Recommended Schedules for Adult (18 years of age and over) Immunization with Pneumococcal Vaccine|
|Age, underlying condition||Type of vaccine||Number of doses and recommended schedule|
|Immunocompetent adults 18 to less than 65 years of age at high risk of IPD due to an underlying medical condition||
|Immunocompetent adults 18 to less than 65 years of age who are residents of long-term care facilities, smokers, persons with alcoholism, homeless persons Table 4 – Footnote 2||
|Adults 65 years of age or older, regardless of risk factors or previous pneumococcal vaccination||
|Adults with an immunocompromising condition (except HSCT)||
|Adult HSCT recipients||
Some experts suggest a dose of pneumococcal conjugate vaccine followed by Pneu-P-23 vaccine for immunocompetent adults at high risk of IPD due to an underlying medical condition, as this may theoretically improve antibody response and immunologic memory. If this strategy is chosen, Pneu-C-13 vaccine should be administered first, followed at least 8 weeks later by Pneu-P-23 vaccine. However, Pneu-P-23 vaccine is the vaccine of choice for these individuals. If only one vaccine can be provided, it should be Pneu-P-23 vaccine.
Individuals who use illicit drugs should be considered for Pneu-P-23 vaccination.
Immunization with Pneu-C-13 vaccine, in addition to Pneu-P-23 vaccine, may be considered for vaccine-naïve, immunocompetent individuals on an individual basis, for the prevention of CAP and IPD caused by the 13 pneumococcal serotypes included in the vaccine.
At least 8 weeks after any previous dose of Pneu-C-13 vaccine and at least 5 years after any previous dose of Pneu-P-23 vaccine.
The Pneu-C-13 vaccine dose should be administered at least 1 year after any previous dose of Pneu-P-23 vaccine.
Side effects of PPV-23 and PCV-13 include typical local and mild systemic reactions, not increased if they are administered in series. There is no current recommendation for boosting PCV-13 in adults. It is important to remember that administration of PCV-13 8 weeks prior to PPV-23 can increase the immunologic response to the strains contained in the PPV-23. The response to the conjugate vaccine is blunted if the PPV-23 is given initially, and one must wait 1 year before administration of PCV-13.
It is prudent to reduce the risks of pneumococcal illness during this time of potentially severe respiratory sequelae of COVID-19, and the newly introduced BC Care Bundle Incentive payment (VIEW) includes a focus on ensuring eligible people receive this vaccine. The HealthlinkBC files #62a and #62b provide key information for discussion with patients. As an additional incentive for delivery of respiratory vaccines in BC, a new MSP fee code introduced Oct 1, 2020, allows one to bill for administration of pneumococcal vaccine in addition to a regular office visit for people (T10040, Dx V05), or if the primary purpose of the visit is for immunization only (B00010, Dx V05). I am still reminded to offer pneumococcal vaccine to my patients when they come in for flu shots. I utilize the evolving evidence base to inform my discussion, with the goal of supporting patients in their immunization decisions in order to improve their health.
Information for patients
- HealthLinkBC File # 62a: Pneumococcal Polysaccharide vaccine https://www.healthlinkbc.ca/healthlinkbc-files/pneumococcal-polysaccharide-vaccine
- HealthLinkBC File #62b: Pneumococcal Conjugate (PCV 13) vaccine https://www.healthlinkbc.ca/healthlinkbc-files/pcv-13-vaccine
References and resources
- Public Health Agency of Canada. Update on the Use of Pneumococcal Vaccines in Adults 65 Years of Age and Older – A Public Health Perspective. Ottawa, Ontario: Public Health Agency of Canada; November 2018 (Link)
- Government of Canada. Pneumococcal Vaccine: Canadian Immunization Guide. Ottawa, ON: Government of Canada; December 2016. (Link)
- BC Centre for Disease Control. Pneumococcal Conjugate Vaccine. Vancouver, BC: BC Centre for Disease Control; August 2018. (Link)
- BC Centre for Disease Control. Pneumococcal Polysaccharide Vaccine. Vancouver, BC: BC Centre for Disease Control; October 2018. (Link)
- Advisory Committee on Immunization Practices. Summary Report June 26-27, 2019. Atlanta, GA: Department of Health and Human Services, Centers for Disease Control and Prevention; June 2019:46-64. (Link)
- Matanock A, Lee G, Gierke R, Kobayashi M, Leidner A, Pilishvili T. Use of 13-valent pneumococcal conjugate vaccine and 23-valent pneumococcal polysaccharide vaccine among adults aged ≥65 years: Updated recommendations of the Advisory Committee on Immunization Practices. MMWR Morb Mortal Wkly Rep. 2019;68:1069–1075. DOI: 10.15585/mmwr.mm6846a5. (Link)
- Hashim A, Dang V, Bolotin S, Crowcroft NS. How and why researchers use the number needed to vaccinate to inform decision making—A systematic review. Vaccine X. 2015;33(6):753-758. DOI: 10.1016/j.vaccine.2014.12.033. (Link)
- Bonten MJM, Huijts SM, Bolkenbass M, et al. Polysaccharide conjugate vaccine against pneumococcal pneumonia in adults. N Engl J Med. 2015;372:1114-1125. DOI: 10.1056/NEJMoa1408544. (Link)
- Ramji J, Kolber MR. Pneumonia vaccine for adults: Is the efficacy as effective as the effort? Tools for Practice. 2018;217. (Link)
- BC Centre for Disease Control. Vaccine Preventable Diseases and Invasive Group A Streptococcal Disease. Vancouver, BC: BC Centre for Disease Control; February 2020. (Link)
- Pneumococcal vaccination: Information for healthcare professionals. Centers for Disease Control and Prevention. Updated November 21, 2019. Accessed January 27, 2021. (Link)
- BC Centre for Disease Control. History of Immunization in BC. Vancouver, BC: BC Centre for Disease Control; August 2020. (Link)