Invasive pneumococcal serotype 3 infection following pneumococcal vaccination in a hematopoietic stem cell transplant patient: A case report

Given the high mortality rate of invasive pneumococcal disease (IPD) in hematopoietic stem cell transplant (HSCT) recipients, vaccination is recommended. These recipients respond to most vaccines; however, their immune response is typically weaker during the first months or years after transplantation, compared with that of healthy individuals. Here, we report a case of IPD with serotype 3 pneumonia and empyema in an HSCT recipient who had received three doses of the 13-valent pneumococcal conjugate vaccine (PCV) and one dose of the 23-valent pneumococcal polysaccharide vaccine; furthermore, the recipient had no relapse, graft-versus-host disease, or use of immunosuppressive agents after allogeneic HSCT for acute myeloid leukemia. Moreover, we discussed the characteristics of serotype 3 Streptococcus pneumoniae, a case series of breakthrough infections with S. pneumoniae in HSCT recipients who received pneumococcal vaccines, and the potential implications for the upcoming PCV15 and PCV20 vaccines for serotype 3.

Effects of sequential vs single pneumococcal vaccination on cardiovascular diseases among older adults: a population-based cohort study

BACKGROUND

Recommendations around the use of 23-valent pneumococcal polysaccharide vaccine (PPSV23) and 13-valent pneumococcal conjugate vaccine (PCV13) seldom focus on potential benefits of vaccine on comorbidities. We aimed to investigate whether sequential vaccination with PCV13 and PPSV23 among older adults would provide protection against cardiovascular diseases (CVD) compared with using a single pneumococcal vaccine.

METHODS

We conducted a Hong Kong-wide retrospective cohort study between 2012 and 2020. Adults aged ≥65 years were identified as receiving either a single or sequential dual vaccination and followed up until the earliest CVD occurrence, death or study end. To minimize confounding, we matched each person receiving a single vaccination to a person receiving sequential vaccination according to their propensity scores. We estimated the hazard ratio (HR) of CVD risk using Cox regression and applied structural equation modelling to test whether the effect of sequential dual vaccination on CVD was mediated via the reduction in pneumonia.

RESULTS

After matching, 69 390 people remained in each group and the median (interquartile range) follow-up time was 1.89 (1.55) years. Compared with those receiving a single vaccine, those receiving sequential dual vaccination had a lower risk of CVD [HR (95% CI): 0.75 (0.71, 0.80), P < 0.001]. Post-hoc mediation analysis showed strong evidence that the decreased CVD risk was mediated by the reduction in all-cause pneumonia.

CONCLUSIONS

Sequential dual pneumococcal vaccination was associated with lower risk of CVD compared with single-dose PCV13 or PPSV23 in older adults. Such additional CVD benefits should be considered when making decisions about pneumococcal vaccination.

Compliance with recommended pneumococcal vaccination schedule in patients treated for rheumatoid arthritis: A retrospective cohort study in the Veterans Affairs population

INTRODUCTION

Invasive pneumococcal disease (IPD) is a leading cause of death. Rheumatoid arthritis (RA) patients are at risk of IPD due to immunosuppressant medications. Up until 2022, two pneumococcal vaccines, the 13-valent Pneumococcal conjugate vaccine (PCV13) and pneumococcal polysaccharide vaccine (PPSV23), were recommended. Despite the recommendation change to give a single 20-valent PCV vaccine (PCV20), some still require multiple vaccinations. There is a need to identify barriers to vaccine uptake.

METHODS

We conducted a retrospective cohort study to assess the on-time vaccination rates for PCV13 and PPSV23 in treated RA patients between 2010 and 2018 using national Veterans Affairs data. Patients > 18 years of age diagnosed with RA and newly initiated on RA treatment were included. Pneumococcal vaccine compliance was assessed by measuring on-time receipt of PCV13 and PPSV23 vaccinations. We identified factors using multivariate logistic regression and described the occurrence of these factors using descriptive statistics.

RESULTS

A total of 39,243 patients were included in the study. Most patients were white (75.8 %), male (85.4 %), on methotrexate therapy (41.4 %). The average age was 62.3 years. The proportion of patients considered vaccine compliant is 43.9 %. The primary independent risk factors for vaccine non-compliance were black/African American race (Odds Ratio [OR] 1.26, 95 % Confidence Interval [CI] 1.19-1.34) or missing/unknown race (OR 1.45, 95 % CI 1.31-1.61), missing/unknown ethnicity (OR 1.21, 1.02-1.43), never married (OR 1.10, 95 % CI 1.02-1.19) or widowed (OR 1.23, 95 % CI 1.12-1.34), diagnosed with congestive heart failure (OR 1.10, 95 % CI 1.00-1.22), or dementia (OR 1.48, 95 % CI 1.16-1.91). The proportion of patients who were non-compliant in patients who were vaccine naïve was 32.1 % and the non-compliance rate for non-naïve patients was 65.3 %.

CONCLUSIONS

Providers should identify barriers to pneumococcal vaccination in RA patients to improve compliance. Efforts to increase vaccination should be tailored to specific high-risk groups.

No Waning of Pneumococcal Vaccine Responses over Time in People with Inflammatory Arthritis: Findings from a Single Centre Cohort

BACKGROUND

Vaccination against pneumococcus reduces the risk of infective events, hospitalisation, and death in individual with inflammatory arthritis, particularly in those on immunomodulating therapy who are at risk of worse outcomes from pneumococcal disease. The objective of this study was to investigate the serological protection following vaccination against pneumococcal serovars over time. Methods: This was a single centre, retrospective cohort study of individuals with rheumatoid arthritis, psoriatic arthritis, or axial spondylarthritis who had previously received the PPSV23 polysaccharide pneumococcal vaccine (Pneumovax). Data were retrieved between January 2021 to August 2023. Dates of previous pneumococcal vaccination were identified using linked primary care records. Serum serotype levels were collected. The primary outcome was serological response defined as a titre ≥0.35 mcg/mL in at least five from a total of 12 evaluated pneumococcal serovars, examined using a Luminex platform. Multivariate logistic regression models adjusting for age, gender, ethnicity, co-morbidities, and the use of prednisolone, conventional synthetic and biological DMARDs were used to determine the odds of a sustained serological response according to time categorised into ≤5 years, 5-10 years, and ≥10 years since vaccination. Results: Serological response was measured in 296 individuals with inflammatory arthritis, with rheumatoid arthritis the most common diagnosis (74% of patients). The median time between pneumococcal vaccine administration and serological assessment was 6 years (interquartile range 2.4 to 9.9). A positive serological response to at least 5 serovars was present in 195/296 (66%) of patients. Time since vaccination did not significantly associate with serological protection compared with those vaccinated <5 years, the adjusted ORs of vaccine response was 1.15 (95% CI 0.64 to 2.07) in those 5-10 years and 1.26 (95% CI: 0.64 to 2.48) in those vaccinated over 10 years ago. No individual variable from the multivariate model reached statistical significance as an independent predictor of vaccine response, although steroid use at the time of vaccine had a consistent detrimental impact on serological immunity. Conclusions: We demonstrated that antibody titres following vaccination against pneumococcal serovars do not appear to wane over time. It appears more critical to focus on maximising the initial vaccine response, which is known to be diminished in this patient population.

Phase 3 trial to evaluate the safety, tolerability, and immunogenicity of V114, a 15-valent pneumococcal conjugate vaccine, followed by 23-valent pneumococcal polysaccharide vaccine 6 months later, in at-risk adults 18-49 years of age (PNEU-DAY): A subgroup analysis by baseline risk factors

Immunocompetent adults with certain medical and behavioral factors are at increased risk of pneumococcal disease. In some countries, sequential vaccination with 13-valent pneumococcal conjugate vaccine (PCV13) followed by 23-valent pneumococcal polysaccharide vaccine (PPSV23) is recommended for at-risk adults. This subgroup analysis from a phase 3 study evaluated the safety, tolerability, and immunogenicity of sequential administration of either V114 (a 15-valent PCV containing serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, 22F, 23F, and 33F) or PCV13, followed 6 months later by PPSV23, in immunocompetent adults 18-49 years of age with pre-defined risk factors for pneumococcal disease. Safety and immunogenicity post-vaccination were analyzed by type and baseline number of risk factors for pneumococcal disease (1 and ≥2 risk factors). This analysis included 1,131 participants randomized 3:1 to receive either V114 or PCV13, followed by PPSV23. The majority (73.1%) of participants had at least one risk factor. Safety and tolerability profiles of V114 and PCV13 were similar across risk factor groups. V114 administered either alone or sequentially with PPSV23 6 months later was immunogenic for all 15 serotypes, including those not contained in PCV13, regardless of the number of baseline risk factors. V114 has the potential to broaden serotype coverage for at-risk adults.

Pneumococcal Pure Polysaccharide Vaccination in Pediatric Patients With Chronic Heart Disease

INTRODUCTION

This study aimed to describe pneumococcal polysaccharide vaccine-23 (PPSV23) vaccination use in high-risk pediatric patients with chronic heart disease (CHD).

METHOD

This was a single-center retrospective cohort study. Patients were included if they were aged 2-18 years and were diagnosed with CHD. The primary outcome was PPSV23 vaccination. Secondary outcomes included missed opportunities and the incidence of infections.

RESULTS

Three hundred ninety-two patients were included; the mean age was 8.8 years. Only 40 patients (10.2%) had documentation of PPSV23 vaccination. Patients had a median number of three clinic visits in 2019. There were 114 cases of pneumonia documented in patients before receiving PPSV23 and one case reported after PPSV23 vaccination.

DISCUSSION

PPSV23 vaccination in high-risk pediatric patients with CHD was low, with many documented missed opportunities for vaccination. This may be attributed to the PPSV23 not being a routine vaccination on the pediatric schedule.

Pneumococcal Polysaccharide Vaccination (PPSV23) in High-Risk Pediatric Patients With Diabetes

OBJECTIVE

The Advisory Committee on Immunization Practices recommends the pneumococcal polysaccharide vaccine (PPSV23) following the pneumococcal conjugate vaccine (PCV13) for pediatric patients aged 2 to 18 years with high-risk medical conditions. The PPSV23 is not a routine immunization for all pediatric patients and children who meet criteria for high-risk conditions may not consistently receive the PPSV23 vaccine, despite current recommendations. The goal of this study was to determine PPSV23 -vaccination rates in the high-risk pediatric patients with type 1 or type 2 diabetes.

METHODS

A single-center retrospective cohort study was conducted. Patients were included if they were 2 to 18 years of age on January 1, 2019, with a diagnosis of diabetes, and had ≥1 encounters within the health care system in 2019. The primary outcome was PPSV23 vaccination rates in the high-risk diabetic pediatric population. Secondary outcomes included identifying missed opportunities for vaccinations and the incidence of invasive pneumococcal infections.

RESULTS

A total of 366 patients met criteria for study inclusion. Patients had a mean age of 13.3 years and were predominantly white (69.8%). A total of 32 (8.7%) patients had documentation of PPSV23 vaccination. Baseline characteristics were comparable between the two groups. There were 32 cases of pneumonia charted before patients received the PPSV23 and one case reported after patients received the PPSV23 vaccination.

CONCLUSIONS

PPSV23 vaccination rates were low in this high-risk diabetic pediatric group, with many -documented missed opportunities for vaccination. This may be attributed to the vaccine not being a -routinely recommended for all pediatric patients.

A Nationwide Digital Multidisciplinary Intervention Aimed at Promoting Pneumococcal Vaccination in Immunocompromised Patients

Immunocompromised patients (IPs) are at high risk for infections, some of which are vaccine-preventable. The Israeli Ministry of Health recommends pneumococcal conjugate vaccine 13 (PCV13) and pneumococcal polysaccharide vaccine 23 (PPSV23) for IP, but vaccine coverage is suboptimal. We assessed the project's effectiveness in improving the pneumococcal vaccination rate among IP. An automated population-based registry of IP was developed and validated at Maccabi Healthcare Services, an Israeli health maintenance organization serving over 2.6 million members. Included were transplant recipients, patients with asplenia, HIV or advanced kidney disease; or those receiving immunosuppressive therapy. A personalized electronic medical record alert was activated reminding clinicians to consider vaccination during IP encounters. Later, IP were invited to get vaccinated via their electronic patient health record. Pre- and post-intervention vaccination rates were compared. Between October 2019 and October 2021, overall PCV13 vaccination rates among 32,637 IP went up from 11.9% (n = 3882) to 52% (n = 16,955) (p < 0.0001). The PPSV23 vaccination rate went up from 39.4% (12,857) to 57.1% (18,652) (p < 0.0001). In conclusion, implementation of targeted automated patient- and clinician-facing alerts, a remarkable increase in pneumococcal vaccine uptake was observed among IP. The outlined approach may be applied to increase vaccination uptake in large health organizations.

The safety of pneumococcal vaccines at the time of sequential schedule: data from surveillance of adverse events following 13-valent conjugated pneumococcal and 23-valent polysaccharidic pneumococcal vaccines in newborns and the elderly, in Puglia (Italy), 2013-2020

Background

Nowadays, two types of anti-pneumococcal vaccine are available: pneumococcal 13-valent conjugate vaccine (PCV13), first licensed in the United States (US) in 2013, and pneumococcal 23-valent polysaccaridic vaccine (PPSV23), first licensed in the US in 1999. These vaccines are recommended in Italy for the immunization of newborns and of the elderly, using a combined sequential schedule for the latter. This report aims to describe the PCV13- and PPSV23-related AEFIs notified in Puglia in 2013-2020, in order to design these products' safety profile in a real-life scenario, three years after the official recommendation about the sequential schedule for people over 60 years of age.

Methods

This is a retrospective observational study. Data were gathered from the list of AEFIs notified following PCV13 and PPSV23 administration in Puglia in 2013-2020. The number of administered vaccine doses was obtained from the regional immunization database. AEFIs were classified according to WHO's algorithm, and causality assessment was carried out in case of serious AEFIs.

Results

From January 2013 to December 2020, 764,183 doses of PCV13 and 40,382 doses of PPSV23 were administered in Puglia. In the same period, 71 PCV13 AEFIs (Reporting Rate: 9.29 x100,000 doses) and 5 PPSV23 AEFIs (Reporting Rate: 12.4 x100,000 doses) were reported. The overall male/female ratio in AEFIs was 0.85. The majority of AEFIs occurred in subjects aged less than 2 (64/76, 84.2%), while 10 out of 76 (13.2%) occurred in patients aged 60 or older. 22 AEFIs were classified as serious and for 12 (54.5%) causality assessment showed a consistent relationship with immunization. The most commonly reported symptoms were fever (Reporting Rate: 4.72 x100,000 doses) and neurological symptoms (Reporting Rate: 3.23 x100,000 doses). Only one death was notified, classified as non-vaccine-related.

Conclusions

The benefit of pneumococcal vaccination appears to be greater than the risk of AEFIs for both PCV13 and PPSV23. In fact, AEFIs occur in less than 0.1‰ of patients and the majority of AEFIs are mild and self-limiting.

A Retrospective Study of Pneumococcal Pneumonia in Hospitalized Patients Aged ≥65 Years in Izumo, Japan: 2010 to 2014

Purpose

In Japan, both a 23-valent pneumococcal polysaccharide vaccine (PPSV23) and a 13-valent pneumococcal conjugate vaccine (PCV13) are available. Although randomized controlled trials have examined the effects of pneumococcal vaccines, few epidemiological studies have investigated the onset of pneumococcal pneumonia in general practice. In Izumo, Shimane Prefecture, Japan, a public subsidy for PPSV23 inoculation began in November 2012.

Patients and Methods

The subjects were pneumonia patients aged 65 and over who were admitted to a hospital in Izumo. This retrospective study analyzed the following data extracted from medical records: pneumococcal pneumonia prevalence, pneumonia severity, mortality rate, PPSV23 vaccination rate, and length of hospital stay. The 2 years before the start of the public subsidy were defined as the early phase, and the 2 years after the subsidy initiation were defined as the late phase. We compared the two phases in terms of PPSV23 vaccination rate, prevalence and severity of pneumococcal pneumonia, and mortality rate.

Results

We investigated data from a total of 1188 and 1086 patients in the early and late phases, respectively. The prevalence of pneumococcal pneumonia was 21.0% and 21.3% in the early and late phases, respectively. The mortality rate from pneumococcal pneumonia was 10.4% and 5.4% in the early and late phases, respectively (p = 0.080), indicating a 50% reduction. The PPSV23 vaccination rate (p < 0.001) and the comorbidity rates of chronic respiratory disease (p = 0.022) and chronic renal disease (p < 0.001) were significantly different between the early and late phases.

Conclusion

This study showed that the rate of in-hospital deaths due to pneumococcal pneumonia was halved after the PPSV23 vaccine was subsidized. The causal relationship between the pneumococcal vaccination rate and the mortality rate of pneumococcal disease was unclear. Further investigation is deemed necessary.

Effect of Pneumococcal Conjugate 13 Valent and Polysaccharide 23 Valent Vaccination on Anti-Pneumococcal Antibody Titer of Hemodialysis Patients: A Randomized Clinical Trial

Background

Pneumococcal infections are a life- threatening disease in hemodialysis patients and vaccination against pneumococcus is an effective prevention. The current study aims to evaluate the immune response and maintenance of the anti-pneumococcal antibody titer in hemodialysis patients to the 23 valent pneumococcal polysaccharide vaccine alone and 13 valent conjugated with 23 valent polysaccharide vaccine.

Materials and Methods

This study is a randomized clinical trial that was performed at Loghman Hakim Hospital in Tehran, Iran in 2017. A total of 70 patients undergoing hemodialysis were randomly assigned to intervention (22 patients) and control (23 patients). In the control group, only one dose of the PPSV23 vaccine while patients in the intervention group were injected initially with PCV13, and then after at least 8 weeks PPSV23 vaccine. The outcome of this study is first and sixth-month antibody titer after injection of the PPSV23 vaccine.

Results

The obtained result showed no significant difference between the two groups in the first month and sixth months. The results indicate that both the intervention group (treated with PCV13+PPSV23) and the control group (treated with PPSV23 only) experienced a significant impact from the first to the sixth month. Additionally, there was a noticeable effect on the levels of anti pneumococcal antibodies during the first to sixth month between the intervention and control groups. In addition, the difference between the antibody titer of the first month and the sixth month was not significant in the two groups.

Conclusion

The anti-pneumococcal antibody titer in hemodialysis patients does not show a clear difference after two vaccine injections and one vaccination.

Pneumococcal vaccination coverage in individuals (16-59 years) with a newly diagnosed risk condition in Germany

Background

Despite recommendations from the German Standing Committee on Vaccination (STIKO), pneumococcal vaccination coverage remains low in vulnerable populations. This study estimated the pneumococcal vaccination coverage rate (VCR) and timing among individuals aged 16–59 years in Germany who were recommended to receive pneumococcal vaccination, according to STIKO.

Methods

A retrospective cohort analysis was conducted using the German InGef database. Individuals aged 16 to 59 years diagnosed with at least one “at-risk” (chronic disease) or “high-risk” (e.g., immunocompromising) condition considered to be at-risk of pneumococcal infection were identified at the time of first diagnosis, between January 1, 2016 and December 31, 2018, and followed up until December 31, 2019. The percentage of cumulative pneumococcal VCR with 95% confidence interval (CI) was reported for each calendar year of follow-up.

Results

There were 334,292 individuals followed for a median of 2.38 (interquartile range (IQR) 1.63–3.13) person years. For individuals aged 16–59 years diagnosed with an incident risk condition in 2016, pneumococcal VCR increased from 0.44% (95% CI 0.41–0.48) in 2016 to 1.24% (95% CI 1.18–1.30) in 2019. In 2019, VCRs were higher in individuals with high-risk conditions compared with at-risk conditions (2.24% (95% CI 2.09–2.40) vs. 0.90% (95% CI 0.85–0.96)). In 2019, VCRs were higher in individuals aged 50 to 59 years compared with individuals aged 16 to 49 years (2.25% (95% CI 2.10–2.41) vs. 0.90% (95% CI 0.84–0.96)). Similar trends were observed in individuals with newly diagnosed risk conditions identified in 2017 and in 2018. Older age, influenza vaccination and increasing number of risk conditions increased the likelihood of pneumococcal vaccination. Median time to vaccination from diagnosis of the risk condition was shorter for high-risk conditions (369.5 days (IQR 155.8–702.0)) compared to at-risk conditions (435.5 days (IQR 196.3–758.8)).

Conclusion

Despite recommendations from STIKO, pneumococcal vaccination coverage remains very low and with long delays in vulnerable individuals aged 16–59 in Germany. Further efforts are required to increase immunization levels and shorten time to vaccination among individuals 16–59 years of age developing conditions with higher susceptibility to pneumococcal infection.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07736-1.

JMM Profile: Streptococcus pneumoniae: sugar-coated captain of the men of death

Streptococcus pneumoniae is a highly adept human pathogen. A frequent asymptomatic member of the respiratory microbiota, the pneumococcus has a remarkable capacity to cause mucosal (pneumonia and otitis media) and invasive diseases (bacteremia, meningitis). In addition, the organism utilizes a vast battery of virulence factors for tissue and immune evasion. Though recognized as a significant cause of pneumonia for over a century, efforts to develop more effective vaccines remain ongoing. The pathogen’s inherent capacity to exchange genetic material is critical to the pneumococcus’ success. This feature historically facilitated essential discoveries in genetics and is vital for disseminating antibiotic resistance and vaccine evasion.

Recent Topics of Pneumococcal Vaccination: Indication of Pneumococcal Vaccine for Individuals at a Risk of Pneumococcal Disease in Adults

Pneumococcal disease is one of the most common and severe vaccine-preventable diseases (VPDs). Despite the advances in antimicrobial treatment, pneumococcal disease still remains a global burden and exhibits a high mortality rate among people of all ages worldwide. The immunization program of the pneumococcal conjugate vaccine (PCV) in children has decreased pneumococcal disease incidence in several countries. However, there are several problems regarding the pneumococcal vaccine, such as indications for immunocompetent persons with underlying medical conditions with a risk of pneumococcal disease, the balance of utility and cost, i.e., cost-effectiveness, vaccine coverage rate, serotype replacement, and adverse events. Especially for individuals aged 19-64 at risk of pneumococcal disease, physicians and vaccine providers should make a rational decision whether the patients should be vaccinated or not, since there is insufficient evidence supporting it. We describe this review regarding topics and problems regarding pneumococcal vaccination from the clinician's point of view.

Effectiveness of Pneumococcal Vaccination Against Hospitalized Pneumococcal Pneumonia in Older Adults: A Prospective, Test-Negative Study

BACKGROUND

Despite use of the 13-valent pneumococcal conjugate vaccine (PCV13) and 23-valent pneumococcal polysaccharide vaccine (PPSV23) over the last decade, the disease burden of pneumococcal pneumonia is still high. We evaluated the field effectiveness of PCV13, PPSV23, and sequential vaccination against pneumococcal pneumonia in older adults.

METHODS

This prospective multicenter study was conducted in adults aged ≥ 65 years with hospitalized community-acquired pneumonia (CAP) between September 2015 and August 2017. The case-control test-negative design was used to estimate vaccine effectiveness (VE) against pneumococcal CAP.

RESULTS

Of 1,525 cases with hospitalized CAP, 167 (11.0%) were identified as pneumococcal CAP. In the elderly aged ≥65 years, the adjusted VE of pneumococcal vaccines against pneumococcal CAP was statistically insignificant: 40.0% (95% CI -10.8% to 67.5%) for PCV13 and 11.0% (95% CI, -26.4% to 37.3%) for PPSV23. However, in the younger subgroup (aged 65-74 years), sequential PCV13/PPSV23 vaccination showed the highest adjusted VE of 80.3% (95% CI 15.9% to 95.4%), followed by single-dose PCV13 (adjusted VE 66.4%; 95% CI 0.8% to 88.6%) and PPSV23 (adjusted VE 18.5%; 95% CI -38.6% to 52.0%).

CONCLUSIONS

Sequential PCV13/PPSV23 vaccination is most effective for preventing pneumococcal CAP among the elderly aged 65-74 years.

Health economic evaluation of introducing a PPSV23-based vaccination programme to adults aged 65 and above, and an extension to the 60-64 age group in Denmark

BACKGROUND

To estimate the health economic consequences of the recently introduced PPSV23 vaccination programme for persons aged 65+ in Denmark and of a potential extension of the programme to include persons aged 60-64 years.

RESEARCH DESIGN AND METHODS

A Markov model was adapted to the Danish healthcare setting to simulate the epidemiological and economic burden of invasive pneumococcal disease and non-bacteremic pneumococcal pneumonia using information from published sources and Danish databases.

RESULTS

We found that the recent introduction of an age-based vaccination programme offering PPSV23 vaccination to the population of persons aged 65+ in Denmark will lead to a societal gain of EUR 72.0 million and prevent 19,707 cases of pneumococcal disease and 1,308 deaths per 1 million persons during the five-year study period.Similarly, we estimate that extending the programme to include persons aged 60-64 will lead to a gain of EUR 14.6 million per 1 million persons and prevent an additional 6,223 cases of pneumococcal disease and 185 deaths.

CONCLUSION

The recent introduction of the age-based vaccination programme offering PPSV23 vaccination to all persons aged 65+ in Denmark is cost-effective. This is also the case if the programme is extended to include persons aged 60-64.

Pneumococcal Disease Outbreak at a State Prison, Alabama, USA, September 1-October 10, 20181

A pneumococcal disease outbreak caused by Streptococcus pneumoniae serotype 12F occurred in a state prison in Alabama, USA. Among 1,276 inmates, 40 cases were identified (3 confirmed, 2 probable, 35 suspected). Close living quarters, substance use, and underlying conditions likely contributed to disease risk. Prophylaxis for close contacts included azithromycin and 23-valent pneumococcal polysaccharide vaccine.

Effectiveness of 23-Valent Pneumococcal Polysaccharide Vaccine against Invasive Pneumococcal Disease in Adults, Japan, 2013-2017

The decline in the proportion of pneumococcal conjugate vaccine (PCV)–covered serotypes among adult invasive pneumococcal disease (IPD) patients might change the overall effectiveness of the 23-valent pneumococcal polysaccharide vaccine (PPSV23) because its effectiveness differs according to serotype. Using the indirect cohort method, we calculated the effectiveness of PPSV23 against IPD among adults in Japan to assess the impact of the national pediatric PCV program. Clinical and epidemiologic information and pneumococcal isolates were collected from IPD patients >20 years of age through enhanced IPD surveillance during April 2013–December 2017. Adjusted effectiveness against PPSV23-serotype IPD was 42.2%. Despite a substantial decline in the proportion of 13-valent PCV serotypes during the study period (45% to 31%), the change in effectiveness for PPSV23-serotype IPD was limited (47.1% to 39.3%) and only marginal in the elderly population (39.9% to 39.4%). The pediatric PCV program had limited impact on PPSV23 effectiveness against IPD in adults.

Immunogenicity following revaccination or sequential vaccination with 23-valent pneumococcal polysaccharide vaccine (PPSV23) in older adults and those at increased risk of pneumococcal disease: a review of the literature

Introduction: Immunogenicity studies evaluating sequential administration of pneumococcal conjugate vaccine (PCV) followed by 23-valent pneumococcal polysaccharide vaccine (PPSV23) or revaccination with PPSV23 have raised concerns that PPSV23 may not elicit higher antibody levels than those measured following PCV or first PPSV23 dose.Areas covered: Recent literature was evaluated for evidence of blunted immune response (hyporesponsiveness), focusing on studies using adequate intervals between doses in accordance with vaccination recommendations. In eight of nine studies that evaluated revaccination with PPSV23 at an interval of ≥5 years after the previous dose, immunoglobulin G geometric mean concentrations and/or opsonophagocytic assay geometric mean titers for most serotypes increased from pre- to post-repeat vaccination and were comparable between repeat and primary vaccination groups post-vaccination. In seven studies in which PPSV23 was administered after PCVs (8 weeks to 1 year apart), responses to PPSV23 were comparable to those seen after initial PCV dose for shared vaccine serotypes. Studies in which PCVs were administered after PPSV23 were not evaluated.Expert opinion: Published data suggest immune responses following repeat vaccination with PPSV23, or sequential PCV/PPSV23 vaccination, are robust, without evidence of hyporesponsiveness. PPSV23 vaccination of at-risk adults is essential to ensure broad protection against all 23 vaccine serotypes.

Response to Shami et al. 'Evaluating the cost-effectiveness of a sequential pneumococcal vaccination compared to single dose vaccination strategy for adults in Hong Kong' (Hum Vacc Immunother 2020)

The recently published article by Shami et al. describes a cost-effectiveness analysis of sequential pneumococcal vaccination with 13-valent pneumococcal conjugate vaccine (PCV13) followed by 23-valent pneumococcal polysaccharide vaccine (PPSV23), compared with a single PPSV23 dose, in adults in Hong Kong. Sequential vaccination was cost-saving versus PPSV23 alone. The model assumed vaccine effectiveness (VE) of 0% for PPSV23 against all-cause non-bacteremic pneumonia; this was based on studies with flawed methodologies and studies that did not evaluate non-bacteremic pneumococcal disease. In recent studies and meta-analyses, PPSV23 VE pneumococcal pneumonia, including against non-bacteremic pneumococcal pneumonia, ranged from 27% to 64%. In other cost-effectiveness analyses, assumptions for PPSV23 VE against non-bacteremic pneumococcal pneumonia, had dramatic effects on cost-effectiveness estimates. Future analyses must carefully consider PPSV23 VE assumptions to ensure accuracy.

Diagnosis and management of Specific Antibody Deficiency

Specific antibody deficiency is a primary immunodeficiency disease recognized by the International Union of Immunology Societies and defined by recurrent respiratory infections with normal immunoglobulins, but diminished antibody responses to polysaccharide antigens after vaccination with the 23 valent pneumococcal polysaccharide vaccine. Clinical immunologists struggle with diagnosis and treatment, because the definition of an adequate response to immunization remains controversial. Specific antibody deficiency is managed clinically with close follow-up and prompt treatment of infections, antibiotic prophylaxis, or immune globulin therapy. Treatment is individualized using clinical judgment and existing practice guidelines, which will likely evolve as more studies become available.

Evaluating the cost-effectiveness of a sequential pneumococcal vaccination compared to single-dose vaccination strategy for adults in Hong Kong

Two vaccines, 23-valent pneumococcal polysaccharide vaccine (PPSV23) and 13-valent pneumococcal conjugate vaccine (PCV13), are widely available for the prevention of pneumococcal disease in adults. However, it is unclear how cost-effective these pneumococcal vaccine choices are in the Hong Kong healthcare environment. We aimed to assess the cost-effectiveness of a sequential administration of PCV13 followed by PPSV23 compared to a single dose of PPSV23 vaccination for pneumococcal disease control in Hong Kong adults aged ≥65 years and individuals aged 20-64 years with immunocompromising and chronic conditions. A previously developed deterministic cohort sequential model was applied to compare the outcomes of two vaccination strategies from a societal perspective. Population-specific model input, including incidence, mortality, case-fatality, risk group distribution, vaccination costs, disease management, and productivity loss, was estimated from a Hong Kong-wide electronic medical database. Costs were valued in US$ in 2017. Vaccination strategies with an incremental cost-effectiveness ratio (ICER, defined as incremental cost per QALY saved) less than one local GDP per capita ($46,193 in 2017) were defined as highly cost-effective. Deterministic sensitivity analyses (SA) were conducted. Compared with single-dose PPSV23, sequential vaccination of PCV13 followed by PPSV23 was cost-saving for adults aged ≥20 years. In the deterministic SA, the base-case results were robust for tested parameter uncertainties. Future vaccination policies should consider the cost-effectiveness of a sequential vaccination strategy as a measure to reduce the vaccine-preventable pneumococcal disease burden in Hong Kong.

Peripheral CD4 T follicular cells induced by a conjugated pneumococcal vaccine correlate with enhanced opsonophagocytic antibody responses in younger individuals

BACKGROUND

PCV13 (conjugated polysaccharide) and PPSV23 (polysaccharide only) are two licensed vaccines targeting S. pneumoniae. The role of CD4 T-cell responses in pneumococcal vaccines among healthy participants and their impact on antibodies is not yet known.

METHODS

Ten adults (5 old and 5 young) received PCV13 (prime) and a year later PPSV23 (boost). Blood samples were collected prior to and multiple time points after vaccination. CD4 T cells responding to CRM₁₉₇, polysaccharide (PS), CRM₁₉₇ conjugated polysaccharide (CPS), PCV13 and PPSV23 vaccines were measured by flow cytometry. Serum antibodies were analyzed via multiplex opsonophagocytosis (MOPA) and pneumococcal IgG assays.

RESULTS

Vaccine-specific CD4 T cells were induced in all ten vaccinees post PCV13. Older vaccinees mounted higher peak responses and those specific for PCV13 and conjugated PS-1 were more polyfunctional compared to the younger group. Vaccine-elicited peripheral T follicular helper (Tfh) cells were only detected in the younger group who also exhibited a higher fold change in OPA titers post both vaccines. Importantly, Tfh cells following PCV13 correlated only with PCV13 serotype specific OPA titers after PPSV23 vaccination.

CONCLUSIONS

These findings demonstrate age related differences in immune response and the potential importance of Tfh in modulating functional antibody responses following pneumococcal vaccination.

Clinical practice guidelines 2019: Indian consensus-based recommendations on pneumococcal vaccination for adults

Similar to the global scenario, pneumococcal diseases are a significant health concern in India. Pneumococcal diseases occur frequently among adults and are largely preventable through vaccines. Globally, several guidelines and recommendations are available for pneumococcal vaccination in adults. However, owing to wide variations in the disease burden, regulatory landscape, and health-care system in India, such global guidelines cannot be unconditionally implemented throughout the country. To address these gaps, the Indian Chest Society and National College of Chest Physicians of India jointly conducted an expert meeting in January 2019. The aim of the discussion was to lay down specific evidence-based recommendations on adult pneumococcal vaccination for the country, with a view to further ameliorate the disease burden in the country. This article presents an overview of the closed-door discussion by the expert members on clinical practice guidelines to be followed for adult pneumococcal vaccination in India.

Environmental factors which can affect the burden of pneumococcal disease and the immune response to pneumococcal vaccines: the need for more precisely delineated vaccine recommendations

Introduction: Precision medicine describes the customization of healthcare tailored to the individual patient. Generally, vaccines are considered as public health tools rather than from the individual patient perspective. However, adult vaccination programs in particular should consider many different factors, at the individual level and also from societal, cultural and country-specific perspectives. Currently, most immunization programs, including those for pneumococcal vaccines, have only been adopted on the basis of age or medical risk. Areas covered: Based on a broad literature search, this review addresses possible environmental factors which can affect the burden of pneumococcal disease and the immune response to pneumococcal vaccines. Expert opinion: Factors which influence the incidence of pneumococcal disease and the reaction against pneumococcal vaccination, including personal conditions, geographic/ethnic factors and social risks, are diverse. To maximize the effects of pneumococcal vaccination, not only for public health but also to induce optimal effects at the individual level, vaccines need to be verified under diverse situations and with collaboration among relevant medical societies, governments, and the pharmaceutical industry. Whereas vaccines are generally considered only from the public health perspective, flexible, comprehensive and tailored pneumococcal immunization programs, with appropriate policy support, can generate a greater positive impact on public health.

Updates on vaccinating the inflammatory bowel disease patient

Many of the therapeutic options for patients with inflammatory bowel disease (IBD) suppress the immune system, which increases the risk of certain infections in these patients. Effective vaccines exist and offer protection against a number of infectious diseases. However, data has shown that IBD patients are inadequately vaccinated and, as a result, are at risk of developing certain preventable infections. Furthermore, gastroenterologists' knowledge regarding the appropriate immunizations to administer to their IBD patients is suboptimal. Areas covered: Over the past several years, there has been a considerable amount of research contributing to our knowledge regarding vaccination of patients with IBD. Expert opinion: This updated review article focuses on the current immunization schedule for the IBD patient and stresses the important role of the gastroenterologist as an active participant in the health maintenance of their IBD patients.

Long-term pneumococcal vaccine immunogenicity following allogeneic hematopoietic stem cell transplantation

Infection with Streptococcus pneumoniae is a life-threatening, but vaccine preventable complication in patients with allogeneic hematopoietic stem cell transplantation (allo-HSCT). The international consensus on post allo-HSCT immunization schedules, starting 3-6 months after HSCT, focuses on short-term immunogenicity while long-term immunogenicity is not well characterized. The current Dutch immunization schedule, which starts at 12 months post allo-HSCT, was developed as a result of concerns on the coverage of long-term immunogenicity in international guidelines. We recently encountered two cases of allo-HSCT recipients who developed invasive pneumococcal disease (IPD) despite adequate revaccinations, which led us to question the immunogenicity of pneumococcal vaccinations in this patient group, and whether the currently existing vaccination schedules are appropriate. We included allo-HSCT recipients, vaccinated from one year after transplantation, and tested antibody responses to pneumococcal vaccination. We also performed a systematic review. Antibody concentrations were measured in 42 of 103 (41%) patients, with a response rate of 85% to PCV13 and 62% to PPSV23-unique serotypes. In six relevant studies, protection rates varied between 64 and 98%. Antibody responses in early and late vaccination schedules were similar, but adequate antibody responses were maintained better after late vaccination. Therefore, we propose a vaccination schedule that combines the advantages of early and late vaccination. This new schedule has been introduced since March 2018 in the two academic hospitals in Amsterdam, The Netherlands.

Coadministration of 13-valent pneumococcal conjugate and quadrivalent inactivated influenza vaccines in adults previously immunized with polysaccharide pneumococcal vaccine 23: a randomized clinical trial

Immune responses to 13-valent pneumococcal conjugate vaccine (PCV13) and quadrivalent inactivated influenza vaccine (QIV) in older adults may vary with coadministration and previous pneumococcal polysaccharide vaccination. This study assessed safety and noninferiority of immune responses to coadministered PCV13 and QIV compared with each vaccine given alone. Adults ≥50 years old preimmunized with ≥1 dose of 23-valent pneumococcal polysaccharide vaccine (PPSV23) ≥1 year before enrollment were randomized 1:1 to receive PCV13+QIV then placebo 1 month later or placebo+QIV then PCV13 1 month later. Administration of PCV13 and placebo was blinded; QIV was administered open-label. Pneumococcal serotype-specific opsonophagocytic activity (OPA) geometric mean titers (GMTs) 1 month after PCV13, and influenza hemagglutination inhibition assay GMTs 1 month after QIV were measured. Prespecified noninferiority was demonstrated by a lower bound of the 2-sided 95% CI for geometric mean ratios >0.5. Safety endpoints included proportions of subjects with adverse and serious adverse events. Of 882 randomized subjects, 846 comprised the evaluable immunogenicity population. Immune responses to all 13 pneumococcal serotypes and all 4 influenza strains 1 month after PCV13+QIV were noninferior to responses 1 month after each vaccine given alone. No safety concerns were identified. Immune responses to coadministered PCV13 and QIV were noninferior to responses after each vaccine given alone, although generally lower for coadministered PCV13. PCV13 and QIV can be administered concomitantly to adults ≥50 years of age preimmunized with PPSV23.

Update on Vaccinating the Patient With Inflammatory Bowel Disease

PURPOSE OF REVIEW

Patients with inflammatory bowel disease (IBD) are at increased risk of infectious diseases independent of their immunosuppression status, and yet, studies suggest that this population is not receiving standard vaccinations at the same rate as the general population. This review seeks to understand why IBD patients may not be receiving recommended immunizations and to provide guidelines on vaccinating this vulnerable population.

RECENT FINDINGS

Inactive vaccines are recommended for patients with IBD regardless of immunosuppression status due to the increased risk for many vaccine-preventable illnesses. Certain live vaccines can be administered to the immunocompromised patient with IBD. Additionally, many patients with IBD will be immunosuppressed some time in their disease course, further increasing their risk for infection. Despite this understanding, patients with IBD have poor vaccination rates. Inadequate knowledge, limited time with patients, and lack of consensus as to who is responsible for identifying and administering vaccinations are some of the most important barriers to vaccinating the patient with IBD. In this review, we discuss guidelines for vaccinating both the immunocompetent and immunosuppressed patient with IBD as well as provide vaccine-specific recommendations. The evidence suggests that patients with IBD are not receiving recommended vaccinations because of misconceptions on the part of patients as well as a paucity of knowledge by their health care team. Educational programs can be successfully implemented to increase knowledge about appropriate vaccinations and can ultimately increase vaccine uptake among patients with IBD. In the end, gastroenterologists and primary care physicians must work together with their patients with IBD to ensure that recommended vaccinations are administered.

Cost-effectiveness analysis of 13-valent pneumococcal conjugate vaccine versus 23-valent pneumococcal polysaccharide vaccine in an adult population in South Korea

In South Korea, the National Immunization Program offers a 23-valent pneumococcal polysaccharide vaccine (PPSV23) for the elderly; however, the 13-valent pneumococcal conjugate vaccine (PCV13) is not included, and vaccination is not offered to younger, at-risk populations. This study offers a comparative analysis of PCV13 and PPSV23 in Korea's adults, stratified by age and risk group. A Markov model with a lifetime horizon was developed from the healthcare perspective. Data sources included the Health Insurance Review & Assessment Service, Korea Centre for Disease Control & Prevention and Korean medical institutions. An expert panel tested data validity. The CAPiTA trial and Cochrane meta-analysis were used to obtain vaccine effectiveness data. Regardless of co-morbidity, when the sequential PCV13-PPSV23 strategy was compared to that using PPSV23-only, in elderly populations, the incremental cost-effectiveness ratio (ICER) was 3,300 USD per quality-adjusted life years (QALY). For the risk group aged ≥65 years, the ICER of the addition of PCV13 over the existing PPSV23-only strategy was 3,404 USD/QALY. However, on replacing PPSV23 with PCV13, for all elderly populations, an ICER of 1,421 USD/QALY resulted; for the risk group aged ≥65 years, the ICER was 1,736 USD/QALY. For the 18-64 year-old risk group, the sequential PCV13-PPSV23 strategy yielded an ICER of 3,629 USD/QALY over the PPSV23-only strategy, and 6,643 USD/QALY compared to no vaccination. Thus, the PCV13→PPSV23 combination strategy for elderly populations was found to be a cost-effective alternative to the current National Immunization Program regardless of co-morbidity. This finding was the same as that for younger, at-risk populations.

A Simple Approach to Pneumococcal Vaccination in Adults

Streptococcus pneumoniae is a bacterium responsible for a spectrum of diseases including lobar pneumonia, meningitis, otitis media, and sinusitis. Invasive pneumococcal disease is responsible for significant morbidity and mortality across the world. Concerted efforts led to the development of two vaccinations, Pneumova × 23 and Prevnar 13, for the prevention of pneumococcal disease. The Advisory Committee on Immunization Practices of the US Centers for Disease Control and Prevention provides vaccination schedules for predisposed adults, but the proposed schedules remain a challenge to health-care providers. We performed a systematic review in PubMed and these specialty group websites to present the pathophysiology of pneumococcal disease, outline different pneumococcal vaccinations, and condense recommendations for vaccination administration.

A case series evaluating the serological response of adult asthma patients to the 23-valent pneumococcal polysaccharide vaccine

BACKGROUND

Asthma is an independent risk factor for invasive pneumococcal disease; however, the immune response of adult asthma patients to pneumococcal vaccination is unknown. We explore the serologic response of patients with moderate to severe asthma to the 23-valent pneumococcal polysaccharide vaccine (PPSV23).

METHODS

Seventeen moderate to severe adult asthma patients that had not been vaccinated against pneumococcus over the 5 previous years were prospectively recruited from a tertiary care asthma clinic. Serum was analyzed for the presence of antibodies to five capsular polysaccharide (CP) antigens (6B, 9V, 19A, 19F, 23F) before and 4 weeks after PPSV23 vaccination.

RESULTS

There was a wide variability in baseline anti-CP antibody concentrations. Other than for serotype 19A, our patients frequently have baseline anti-CP antibody concentrations below 1 µg/mL (35% for serotype 19F, 41% for serotypes 9V and 23F, and 59% for serotype 6B). All post-vaccination geometric mean antibody concentrations were significantly higher than baseline. In the 31 tests where the baseline antibody concentration was <1 µg/mL, 77.4% had at least a twofold increase post-vaccination. Despite this, a large proportion of post-vaccination anti-CP antibody concentrations remained <1 µg/mL (51.6% of tests). Nine patients had at least one anti-CP antibody concentration <1 µg/mL post-vaccination. There was no difference between these patients and the remaining eight patients in demographic or clinical variables.

CONCLUSIONS

Patients with moderate to severe asthma have variable baseline and low post-vaccination antibody concentrations to common CP antigens included in the PPSV23 vaccine. The clinical relevance of these observations remains to be determined since the threshold concentration in adults required for clinical protection from invasive pneumococcal disease is uncertain.

Serotype distribution and antimicrobial susceptibility of Streptococcus pneumoniae strains isolated in Japan after introduction of the routine immunization program

Pneumococcal vaccines have reduced the incidences of Streptococcus pneumoniae infections among children and adults, but a relative increase in the prevalence of non-vaccine serotypes has been reported. To follow the changing epidemiology of pneumococcal diseases, capsular serotyping and antimicrobial susceptibility testing was performed on 534 pneumococcal isolates obtained from a hospital in Japan after routine immunization was launched, between October 2014 and May 2016. Serotype distributions and antimicrobial susceptibilities were evaluated among the total patient population, and were compared by age and sample groups and by serotype group, respectively. Serotypes targeted by the 13-valent pneumococcal conjugate vaccine (PCV13) were identified in 14.6%, 44.5%, and 40.2% of the samples from the <5, 5-64, and ≥65 year age groups, respectively. The 23-valent pneumococcal polysaccharide vaccine serotypes (PPSV23) were identified in 42.4%, 68.2%, and 63.1% of the samples, respectively; whereas non-PCV13 serotypes or non-PPSV serotypes (NVT) comprised 46.8% of all isolates. Among NVT, strain 35B was the most frequently isolated, followed by 15A, particularly in sputum samples collected from children <5 years old. Meanwhile, serotype 3, which is targeted by the PCV13 and PPSV23, was the most prevalent among patients aged ≥65 and 5-64 years. Antimicrobial susceptibility testing revealed that 88.9% and 81.0% of serotype 35B was non-susceptible to penicillin and meropenem, respectively, and 89.4% of 15A was non-susceptible to penicillin. Our data suggest rapid effects of pneumococcal vaccines and progression of serotype replacement. Besides invasive potential, the increased prevalence of non-vaccine serotypes with highly non-susceptible to penicillin was a concern. Continuous monitoring of pneumococcal serotypes and antimicrobial susceptibility is necessary for developing optimal preventive strategies.

Serotype Changes and Drug Resistance in Invasive Pneumococcal Diseases in Adults after Vaccinations in Children, Japan, 2010-2013

Pneumococcal conjugate vaccination of children is associated with penicillin-resistant Streptococcus pneumoniae in adults.

After 7-valent pneumococcal conjugate vaccine (PCV) for children was introduced in Japan in November 2010, we examined changes in Streptococcus pneumoniae serotypes and in genetic antimicrobial drug resistance of isolates from adults with invasive pneumococcal diseases. During April 2010–March 2013, a total of 715 isolates were collected from adults with invasive pneumococcal diseases. Seven-valent PCV serotypes in adults decreased from 43.3% to 23.8%, most noticeably for serotype 6B. Concomitantly, 23-valent pneumococcal polysaccharide vaccine (PPSV23) serotypes decreased from 82.2% to 72.2%; non-PPSV23 serotypes increased from 13.8% to 25.1%. Parallel with serotype changes, genotypic penicillin-resistant S. pneumoniae decreased from 32.4% to 21.1%, and 6 non-PPSV23 serotypes emerged (6D, 15A, 15C, 16F, 23A, and 35B). Respective vaccine coverage rates for 13-valent PCV and PPSV23 differed by disease: 73.9% and 84.3% for patients with pneumonia, 56.4% and 69.2% for patients with bacteremia and sepsis, and 45.7% and 69.3% for patients with meningitis.

Is 13-Valent Pneumococcal Conjugate Vaccine (PCV13) Combined With 23-Valent Pneumococcal Polysaccharide Vaccine (PPSV23) Superior to PPSV23 Alone for Reducing Incidence or Severity of Pneumonia in Older Adults? A Clin-IQ

Pneumonia infection is a significant cause of morbidity and mortality worldwide. In addition to the public health concerns, pneumonia also accounts for a significant cost to the health care system. Currently there are two leading vaccines targeted against S. pneumoniae: 23-valent pneumococcal polysaccharide vaccine (PPSV23) and 13-valent pneumococcal conjugate vaccine (PCV13). Until recently the recommendation for adult pneumonia vaccination has been a single dose of PPSV23 for all adults 65 years and older. However, concerns were raised regarding the vaccine's efficacy due to the persistent burden of pneumococcal disease in the elderly population. This paper focuses on two trials which evaluate the safety and efficacy of PCV13 in the adult population. The first study reveals improved immune response with the addition of PCV13 to PPSV23, while the second shows PCV13 was effective in the prevention of vaccine-type community-acquired pneumonia. The two studies observed adequate safety profiles for PCV13 in series with PPSV23 and with PCV13 compared to placebo.

Committee On Infectious Diseases. Immunization for Streptococcus pneumoniae infections in high-risk children

Routine use of the pneumococcal conjugate vaccines (PCV7 and PCV13), beginning in 2000, has resulted in a dramatic reduction in the incidence of invasive pneumococcal disease (IPD) attributable to serotypes of Streptococcus pneumoniae contained in the vaccines. The Advisory Committee on Immunization Practices of the Centers for Disease Control and Prevention and the American Academy of Pediatrics recommend the expanded use of PCV13 in children 6 through 18 years of age with certain conditions that place them at elevated risk of IPD. This statement provides recommendations for the use of PCV13 in children 6 through 18 years. A single dose of PCV13 should be administered to certain children in this age group who are at elevated risk of IPD. Recommendations for the use of PCV13 in healthy children and for pneumococcal polysaccharide vaccine (PPSV23) remain unchanged.

Safety and immunogenicity of 13-valent pneumococcal conjugate vaccine formulations with and without aluminum phosphate and comparison of the formulation of choice with 23-valent pneumococcal polysaccharide vaccine in elderly adults: a randomized open-label trial

This randomized open-label trial was designed to provide preliminary immunogenicity and safety data to support development of the pediatric 13-valent pneumococcal conjugate vaccine (PCV13) for adults. The aims were to: identify an age-appropriate PCV13 formulation, i.e., with (n = 309) or without (n = 304) aluminum phosphate (AlPO 4); compare the selected PCV13 formulation (n = 309) with 23-valent pneumococcal polysaccharide vaccine (PPSV23; n = 301); and, together with an extension study, assess sequential use of pneumococcal vaccines at 1-year intervals in adults aged ≥65 years (n = 105) not pre-vaccinated with PPSV23. Immune responses were measured by ELISA and opsonophagocytic activity assays 1 month postvaccination. Immunoglobulin G responses elicited by PCV13 with AlPO 4 and PCV13 without AlPO 4 were similar for the majority, and noninferior for all PCV13 serotypes. PCV13 with AlPO 4 was generally more reactogenic, with reactions mainly mild or moderate. Thus, PCV13 with AlPO 4 (hereafter PCV13) became the selected formulation. Immune responses to PCV13 were noninferior for all but one serotype and for most PCV13 serotypes superior to PPSV23. Vaccine sequence assessments showed that for PCV13/PPSV23, the initial PCV13 dose generally enhanced responses to a subsequent PPSV23 dose, compared with PPSV23 alone. For PCV13/PCV13, a second dose did not enhance the first dose response when given after 1 year. For PCV13/PPSV23/PCV13, priming with PCV13 (vaccination 1) did not protect against lower responses induced by PPSV23 to subsequent PCV13 (vaccination 3). In conclusion, the pediatric PCV13 formulation with AlPO 4 is well tolerated and immunogenic in adults, is generally more immunogenic than PPSV23, and subsequent vaccination with PPSV23 is possible if required.

Immunogenicity and safety of a 13-valent pneumococcal conjugate vaccine in adults 70 years of age and older previously vaccinated with 23-valent pneumococcal polysaccharide vaccine

BACKGROUND

The currently recommended single dose of the 23-valent pneumococcal free polysaccharide vaccine (PPSV23) for adults 65 years of age and older does not provide extended protection into older age. This reflects a significant unmet medical need for alternative strategies to protect older adults against pneumococcal infection, which may be met by the 13-valent polysaccharide conjugate vaccine (PCV13).

METHODS

We performed a randomized, modified double-blind trial in 936 adults aged 70 years and older who had previously received PPSV23 at least 5 years before study entry and were now vaccinated with PCV13 or PPSV23. At 1 year after enrollment, all subjects received a follow-on dose of PCV13. Anti-pneumococcal opsonophagocytic activity (OPA) titers were measured before and at 1 month after each vaccination.

RESULTS

Following the enrollment vaccination, OPA titers were significantly greater in the PCV13 group compared to the PPSV23 group for 10 of the 12 serotypes common to both vaccines and to serotype 6A which is unique to PCV13. Responses were noninferior for the other 2 common serotypes. Responses to PCV13 given at 1 year were generally lower in the group that received PPSV23 at enrollment.

CONCLUSION

In adults aged 70 years and older previously vaccinated with PPSV23, PCV13 was significantly more immunogenic than PPSV23 for most of the common serotypes and for serotype 6A. The OPA responses after a follow-on dose of PCV13 one year later indicate that a prior dose of PPSV23, but not PCV13, diminishes the response to the subsequent administration of PCV13.

Influence of initial vaccination with 13-valent pneumococcal conjugate vaccine or 23-valent pneumococcal polysaccharide vaccine on anti-pneumococcal responses following subsequent pneumococcal vaccination in adults 50 years and older

BACKGROUND

Unlike free polysaccharide vaccines, pneumococcal polysaccharide conjugate vaccines (PCVs) induce a T cell-dependent immune response and have the potential to provide an extended duration of protection with repeated vaccinations.

METHODS

This was an extension of a previous study in pneumococcal vaccine-naïve adults aged 50-64 years in which adults 60-64 years of age were given 13-valent PCV (PCV13) or 23-valent pneumococcal polysaccharide vaccine (PPSV23) and adults aged 50-59 were given PCV13. In this follow up study conducted about 4 years later, the 60-64 year olds initially given PCV13 received PCV13 or PPSV23, and those initially given PPSV23 received another PPSV23. All adults aged 50-59 years were re-vaccinated with PCV13. Anti-pneumococcal opsonophagocytic activity (OPA) titers were measured before and 1 month after vaccination.

RESULTS

A second PCV13 given about 4 years after a first vaccination induced OPA titers that were significantly higher than those following the initial vaccination for 7 of 13 serotypes in the older group, and 6 of 13 serotypes in the younger group, and responses to the remaining serotypes were largely non-inferior. In contrast, OPA titers following revaccination with PPSV23 were statistically significantly lower for 9 of the 13 serotypes, and non-inferior for the remaining serotypes, when compared to the responses to the first PPSV23. OPA titers in the older adults who received PPSV23 after initial PCV13 were significantly higher than those following a first PPSV23 for 10 of the 13 serotypes.

CONCLUSION

In adults 50 to 64 years of age, initial vaccination with PCV13 establishes an immune state that results in recall anti-pneumococcal responses upon subsequent vaccination with either conjugated or free polysaccharide vaccine. In contrast, initial vaccination with PPSV23 results in an immune state in which subsequent PPSV23 administration yields generally lower responses compared with the initial responses.