The effect of underlying clinical conditions on the risk of developing invasive pneumococcal disease in England

Diabetes as a risk factor for pneumococcal disease and severe related outcomes and efficacy/effectiveness of vaccination in diabetic population. Results from meta-analysis of observational studies

AIMS

To collect all available evidence on the effect of diabetes mellitus (DM) as a risk factor for pneumococcal disease incidence and related complications, and on the efficacy/effectiveness of vaccines in patients with DM.

METHODS

Two distinct systematic searches on MEDLINE, Cochrane, ClinicalTrials.gov and EMBASE databases were performed, one for each meta-analysis, collecting all observational (cohort and case-control) studies and randomized clinical trials performed on humans up to June 1st, 2023.

RESULTS

We retrieved 36 observational studies comparing risk for pneumococcal disease and related complications in people with or without DM, and 11 studies (1 randomized clinical trial and 10 observational studies) assessing conjugated and polysaccaridic vaccines efficacy/effectiveness on preventing such outcomes. People with DM were at higher risk for Invasive Pneumococcal Disease (unadjusted OR 2.42 [2.00; 2.92]); Case-Fatality Rate (unadjusted OR 1.61 [1.25; 2.07], Pneumococcal pneumonia (unadjusted OR 2.98 [2.76; 3.22), and Intensive care unit admission for pneumococcal disease (unadjusted OR 2.09 [1.20; 3.66]). In diabetic individuals vaccinated with conjugated vaccine, incidence of pneumonia specific for vaccine type in a clinical trial (OR 0.237 [0.008; 0.704]), and hospitalization for overall pneumonia during the year following the polysaccharide vaccination in observational studies (unadjusted OR 0.63 [0.45-0.89]) were significantly lower in comparison with unvaccinated DM subjects, with no significant differences for other outcomes.

CONCLUSIONS

People with diabetes mellitus are at higher risk for less favourable course of pneumococcal disease and should be therefore targeted in vaccination campaigns; more evidence needs to be collected on vaccination outcomes in people with diabetes.

Cost-Effectiveness of 20-Valent Pneumococcal Conjugate Vaccine in Argentinean Adults

INTRODUCTION

In Argentina, vaccination with 13-valent pneumococcal conjugate vaccine (PCV13) followed by 23-valent pneumococcal polysaccharide vaccine (PPSV23; PCV13 → PPSV23) has been recommended for all adults aged ≥ 65 years and younger adults with chronic medical ("moderate-risk") or immunocompromising ("high-risk") conditions since 2017. With the approval of a 20-valent PCV (PCV20), we evaluated the cost-effectiveness of PCV20 versus current recommendations for moderate-/high-risk adults aged 18-64 years and all adults 65-99 years.

METHODS

A probabilistic cohort model was used to project lifetime outcomes and costs associated with invasive pneumococcal disease (IPD) and all-cause non-bacteremic pneumonia (NBP), and the expected impact of vaccination. Clinical outcomes were projected annually based on Argentinean data. Economic costs were estimated based on cases and corresponding medical costs (adjusted to 2023 USD) and costs of vaccine and administration. Cost-effectiveness of PCV20 was evaluated versus the current strategy, PCV13 → PPSV23, and alternatively, versus sequentially administered 15-valent PCV and PPSV23 (PCV15 →  PPSV23), and presented as cost per quality-adjusted life year gained; a healthcare system perspective was used. Costs and benefits were discounted at 3%/year.

RESULTS

PCV20 in lieu of PCV13 → PPSV23 among moderate-/high-risk adults aged 18-64 years and all adults 65-99 years (N = 13.4M) prevented 3838 IPD, 4377 inpatient NBP, and 6003 outpatient NBP cases, and 1865 disease-related deaths; relative to PCV15 → PPSV23 the corresponding reductions were 2775, 3285, 4518, and 1348. PCV20 was projected to be the dominant strategy versus PCV13 → PPSV23 and PCV15 → PPSV23 as overall costs were lower by $87.6M and $80.8M, respectively. In probabilistic sensitivity analyses, PCV20 was dominant (i.e., more effective, less costly) in 100% of 1000 simulations.

CONCLUSIONS

Analyses suggest implementing a PCV20 vaccination program in moderate-/high-risk adults aged 18-64 years and all adults ≥ 65 years-in lieu of PCV13 → PPSV23-would yield substantial reductions in pneumococcal disease and would be cost saving to the Argentinean healthcare system.

The effectiveness of revaccination with pneumococcal polysaccharide vaccine for preventing pneumococcal disease in older adults in England: A population-based cohort study

BACKGROUND

Pneumococcal disease in older adults in the United Kingdom is rising despite immunisation. A key gap in the literature is the clinical effectiveness of revaccination with the pneumococcal polysaccharide vaccine (PPV23).

METHODS

A cohort study was performed in England, using electronic medical records in the Clinical Practice Research Datalink. Individuals aged ≥64 years and vaccinated with PPV23 were included. Rates of hospitalised pneumonia (HP) and invasive pneumococcal disease (IPD) were compared between individuals receiving a single PPV23 dose versus those receiving two doses using multi-level Cox proportional hazards models. Propensity score weighting was performed to minimise the effect of confounding covariates across the comparison groups.

RESULTS

Between 2006 and 2019, there were 462 505 eligible participants. Of those, 6747 (1·5 %) received revaccination. Two doses compared to one dose was associated with an increased risk of HP (adjusted Hazard Ratio [aHR] 1·95; 95 %CI 1·74-2·20) and IPD (aHR 1·44; 95 %CI 1·41-1·46). In participants aged 64-74 years PPV23 revaccination was associated with more IPD (aHR 2·02; 95 %CI 1·75-2·33) and HP (aHR 1·46; 95 %CI 1·42-1.49). In those aged ≥75 years PPV23 revaccination was associated with more HP (aHR 1·12; 95 %CI 1·08-1·16) with no statistically significant difference detected in risk of IPD (aHR 1·20; 95 %CI 0·94-1·52).

CONCLUSIONS

No clear benefit of PPV23 revaccination was measured in older adults in this observational study. The small proportion of revaccinated subjects limits the strength of the conclusions. Further research evaluating the clinical effectiveness of PPV23 revaccination is required.

Can Lacticaseibacillus rhamnosus CRL1505 postbiotic improve emergency myelopoiesis in immunocompromised mice?

We evaluated whether viable and non-viable Lacticaseibacillus rhamnosus CRL1505 (Lr05V or Lr05NV, respectively) was able to improve emergency myelopoiesis induced by Streptococcus pneumoniae (Sp) infection. Adult Swiss-mice were orally treated with Lr05V or Lr05NV during five consecutive days. The Lr05V and Lr05NV groups and untreated control group received an intraperitoneal dose of cyclophosphamide (Cy-150 mg/kg). Then, the mice were nasally challenged with Sp (107 UFC/mice) on day 3 post-Cy injection. After the pneumococcal challenge, the innate and myelopoietic responses were evaluated. The control group showed a high susceptibility to pneumococcal infection, an impaired innate immune response and a decrease of hematopoietic stem cells (HSCs: Lin-Sca-1+c-Kit+), and myeloid multipotent precursors (MMPs: Gr-1+Ly6G+Ly6C-) in bone marrow (BM). However, lactobacilli treatments were able to significantly increase blood neutrophils and peroxidase-positive cells, while improving cytokine production and phagocytic activity of alveolar macrophages. This, in turn, led to an early Sp lung clearance compared to the control group. Furthermore, Lr05V was more effective than Lr05NV to increase growth factors in BM, which allowed an early HSCs and MMPs recovery with respect to the control group. Both Lr05V and Lr05NV were able to improve BM emergency myelopiesis and protection against respiratory pathogens in mice undergoing chemotherapy.

Impact of a clinical pharmacist's intervention on pneumococcal vaccination in a population of at- risk hospitalized patients: The IP-VAC study

OBJECTIVES

The aim of this study was to evaluate the impact of clinical pharmacist intervention on compliance with pneumococcal vaccination (PV) recommendations in hospitalized patients.

METHODS

This was a prospective, single-center, before-and-after study conducted in 2019-2020. Patients had to be over 18 years of age, at risk of pneumococcal infection, and with no PV. No changes were made in the observational phase. During the interventional phase, the clinical pharmacist discussed a prescription for preventive PV and a mention in the discharge letter. A pharmaceutical consultation sensitized the patient to the interest of PV. The clinical pharmacist ensured that a complete vaccination protocol would be carried out by the retail pharmacist within 3 months of hospitalization.

RESULTS

One hundred and sixty-seven (167) patients were included. In the observational phase, 2.3% of patients received a complete vaccination protocol after discharge from primary care. The rate increased to 63.8% after the clinical pharmacist's intervention (p < 0.001). Vaccines were prescribed by hospital physicians in 97.5% of cases, while 40% of discharge letters included the indication for PV.

CONCLUSION

The clinical pharmacist's intervention led to delivery of a complete PV protocol after discharge for over half the patients. This study demonstrated the feasibility of a pharmaceutical intervention to promote PV in hospital activities.

Outcomes among Thai children with risk conditions hospitalized for pneumococcal disease (invasive or non-bacteraemic pneumonia): A multi-centre, observational study

Objective

To describe the risk condition status and clinical outcomes among Thai children hospitalized with pneumococcal disease.

Methods

In this retrospective analysis, children with invasive pneumococcal disease (IPD) or x-ray-confirmed non-bacteraemic pneumococcal pneumonia (NBPP) were identified from nine hospitals in Thailand between 2010 and 2019. Data on risk factors and outcomes were extracted from medical records.

Results

In total, 413 cases were identified: 319 IPD and 94 NBPP. Overall, 133 (32.2%) patients were admitted to intensive care units and 11/406 (2.7%) died. Twenty-seven percent of IPD cases had at-risk conditions and 15% had high-risk conditions. Most IPD cases (32.9%) occurred in children aged 2-4 years, and most NBPP cases (28.7%) occurred in infants aged 0-11 months. Of 51 Streptococcus pneumoniae isolates collected, 41 (80%) were pneumococcal 13-valent conjugate vaccine serotypes. Only 5.1% of children had received a pneumococcal vaccine.

Conclusions

Most children with IPD and NBPP did not have high-risk or at-risk conditions, while 42% had at-risk or high-risk conditions for pneumococcal disease. Very few children in the cohort had received any type of pneumococcal vaccine. Increasing the availability of pneumococcal conjugate vaccines should be considered to reduce the burden of pneumococcal disease among children in Thailand.

Distribution of serotypes causing invasive pneumococcal disease in older adults from high-income countries and impact of pediatric and adult vaccination policies

BACKGROUND

Neither indirect protection through use of 13-valent and 10-valent pneumococcal conjugate vaccines (PCV13 and PCV10) in pediatric National Immunization Programs (NIPs) nor direct vaccination with the 23-valent polysaccharide vaccine have eliminated vaccine serotype invasive pneumococcal disease (IPD) in older adults. Vaccinating older adults with higher-valency PCV15 and PCV20 could address remaining IPD due to pediatric PCV serotypes plus additional IPD due to serotypes included in these vaccines.

METHODS

We collected serotype-specific IPD data in older adults (≥65 years in most countries), from national or regional surveillance systems or hospital networks of 33 high-income countries. Data were from official government websites, online databases, surveillance system reports, published literature, and personal communication with in-country investigators. Average percentages of IPD serotypes were calculated.

RESULTS

Among 52,905 cases of IPD with a serotype identified, PCV13 serotypes accounted for 33.7% of IPD (55.8% and 30.6% for countries with PCV10 and PCV13 in the pediatric NIP), most commonly serotypes 3 (14.9%) and 19A (7.0%). PCV15 and PCV20 would cover an additional 10.4% and 32.9% of older adult IPD beyond PCV13 serotypes (PCV10 countries: 7.7% and 23.3%; PCV13 countries: 10.6% and 34.6%). The most common of these additional serotypes were 8 (9.9%), 22F (7.9%), 12F (4.6%), and 11A (3.3%). PPSV23 policies for older adults were not correlated with lower IPD percentages due to PPSV23 serotypes.

CONCLUSIONS

Vaccinating older adults with higher-valency PCVs, especially PCV20, could substantially reduce the remaining IPD burden in high-income countries, regardless of current PCV use in pediatric NIPs and adult PPSV23 policies.

Cost-utility analysis of the use of the 20-valent anti-pneumococcal vaccine (PCV20) in adults older than 60 years in Spain

BACKGROUND AND OBJECTIVES

A cost-utility analysis was conducted to assess the efficiency of implementing a PCV20 vaccination strategy in the Spanish adult population older than 60 years, for the prevention of non-bacteremic pneumococcalpneumonia (NBP) and invasive pneumococcal disease (IPD).

METHODS

A Markov model, with annual cycles and a time horizon of 10 years was used. The analysis population was stratified by age and risk groups. The comparator was the sequential vaccination with the 15-valent pneumococcal conjugate vaccine (PCV15) followed by one dose of the pneumococcal polysaccharide vaccine (PPV23). The base case analysis was performed from the National Healthcare System (NHS) perspective including direct costs (€2018) and applying a discount of 3% to future costs and outcomes. Alternative scenarios explored a shorter time horizon (5 years), the societal perspective and other available vaccination strategies. All the parameters and assumptions were validated by a panel of experts. To evaluate the robustness of the model, deterministic and probabilistic sensitivity analyses (PSA) were carried out.

RESULTS

The results of the study showed that the vaccination strategy with PCV20 is a dominant option compared to the sequential regimen (PCV15 + PPSV23), resulting in direct cost savings of €85.7 M over 10 years, with a small increase in quality-adjusted life years (QALYs). PCV20 vaccination avoided 2,161 cases of IPD, 19,470 of NBP and 3,396 deaths and according to the PSA, the probability of PCV20 being cost-effective compared to a sequential regimen (PCV15 + PPSV23) was 100%.

CONCLUSIONS/RECOMMENDATIONS

In the Spanish adult population older than 60 years, the vaccination strategy with one dose of PCV20 is more effective and less expensive (dominant) than vaccination with a sequential schedule with PCV15 and PPSV23.

Clinical and economic burden of pneumococcal disease among adults in Sweden: A population-based register study

Pneumococcal disease is a major cause of clinical and economic burden worldwide. This study investigated the burden of pneumococcal disease in Swedish adults. A retrospective population-based study was conducted using Swedish national registers, including all adults aged ≥18 years with a diagnosis of pneumococcal disease (defined as pneumococcal pneumonia, meningitis, or septicemia) in inpatient or outpatient specialist care between 2015-2019. Incidence and 30-day case fatality rates, healthcare resource utilization, and costs were estimated. Results were stratified by age (18-64, 65-74, and ≥75 years) and the presence of medical risk factors. A total of 10,391 infections among 9,619 adults were identified. Medical factors associated with higher risk for pneumococcal disease were present in 53% of patients. These factors were associated with increased pneumococcal disease incidence in the youngest cohort. In the cohort aged 65-74 years, having a very high risk for pneumococcal disease was not associated with an increased incidence. Pneumococcal disease incidence was estimated at 12.3 (18-64), 52.1 (64-74), and 85.3 (≥75) per 100,000 population. The 30-day case fatality rate increased with age (18-64: 2.2%, 65-74: 5.4%, ≥75: 11.7%), and was highest among septicemia patients aged ≥75 (21.4%). The 30-day average number of hospitalizations was 1.13 (18-64), 1.24 (64-74) and 1.31 (≥75). The average 30-day cost/infection was estimated at €4,467 (18-64), €5,278 (65-74), and €5,898 (≥75). The 30-day total direct cost of pneumococcal disease between 2015-2019 was €54.2 million, with 95% of costs from hospitalizations. The clinical and economic burden of pneumococcal disease in adults was found to increase with age, with nearly all costs associated with pneumococcal disease from hospitalizations. The 30-day case fatality rate was highest in the oldest age group, though not negligible in the younger age groups. The findings of this study can inform the prioritization of pneumococcal disease prevention in adult and elderly populations.

Chronic medical conditions associated with invasive pneumococcal diseases in inpatients in teaching hospitals in São Paulo city: Estimating antimicrobial susceptibility and serotype-coverage of pneumococcal vaccines

BACKGROUND

Chronic conditions increase the risk of invasive pneumococcal diseases (IPD). Pneumococcal vaccination remarkably reduced IPD morbimortality in vulnerable populations. In Brazil, pneumococcal vaccines are included in the National Immunization Program (PNI): PCV10 for < 2 years-old, and PPV23 for high risk-patients aged ≥ 2 years and institutionalized ≥ 60 years. PCV13 is available in private clinics and recommended in the PNI for individuals with certain underlying conditions.

METHODS

A retrospective study was performed using clinical data from all inpatients from five hospitals with IPD from 2016 to 2018 and the corresponding data on serotype and antimicrobial-non-susceptibility of pneumococcus. Vaccine-serotype-coverage was estimated. Patients were classified according to presence of comorbidities: healthy, without comorbidities; at-risk, included immunocompetent persons with specific medical conditions; high-risk, with immunocompromising conditions and others RESULTS: 406 IPD cases were evaluated. Among 324 cases with information on medical conditions, children < 5 years were mostly healthy (55.9%), while presence of comorbidity prevailed in adults ≥ 18 years old (> 82.0%). Presence of ≥1 risk condition was reported in ≥ 34.8% of adults. High-risk conditions were more frequent than at-risk in all age groups. Among high-risk comorbidity (n = 211), cancer (28%), HIV/AIDS (25.7%) and hematological diseases (24.5%) were the most frequent. Among at-risk conditions (n = 89), asthma (16.5%) and diabetes (8.1%) were the most frequent. Among 404 isolates, 42.9% belonged to five serotypes: 19A (14.1%), 3 (8.7%), 6C (7.7%), 4 and 8 (6.2% each); 19A and 6C expressed antimicrobial-non-susceptibility. The vaccine-serotype-coverage was: PCV10, 19.1%, PCV13, 43.8%; PCV15, 47.8%; PCV20, 62.9%; PCV21, 65.8%, and PPV23, 67.3%. Information on hospital outcome was available for 283 patients, of which 28.6% died. Mortality was 54.2% for those with meningitis.

CONCLUSION

Vaccine with expanded valence of serotypes is necessary to offer broad prevention to IPD. The present data contribute to pneumococcal vaccination public health policies for vulnerable patients, mainly those with comorbidity and the elderly.

Cost-effectiveness of use of 20-valent pneumococcal conjugate vaccine among adults in Germany

OBJECTIVES

Despite national recommendations for use of pneumococcal vaccines, rates of community-acquired pneumonia (CAP) and invasive pneumococcal disease (IPD) remain high in Germany. New pneumococcal conjugate vaccines (PCVs) with expanded coverage have the potential to reduce the pneumococcal disease burden among adults.

METHODS

Using a Markov model, we evaluated the lifetime outcomes/costs comparing 20-valent PCV (PCV20) with standard of care (SC) vaccinations for prevention of CAP and IPD among adults aged ≥60 years and at-risk adults aged 18-59 years in Germany. PCV20 also was compared with sequential vaccination with 15-valent PCV (PCV15) followed by PPSV23 in a scenario analysis.

RESULTS

Over the course of a lifetime (82 years), use of PCV20vs. SC would prevent 54,333 hospitalizations, 26368 outpatient CAP cases, 10946 disease-related deaths yield 74,694 additional life-years (LYs), while lowering total medical costs by 363.2 M €. PCV20 remained cost saving (i.e. dominant) versus SC even in numerous sensitivity analyses, including a sensitivity analysis assuming moderate effectiveness of the SC pneumococcal polysaccharide vaccine against noninvasive pneumococcal CAP. In several scenario analyses and a probabilistic sensitivity analysis, PCV20 was also cost-saving compared toPCV15 PPSV23 vaccination.

CONCLUSIONS

One dose of PCV20 among adults aged ≥60 years and adults aged 18-59 years with moderate- and high-risk conditions wouldsubstantially reduce pneumococcal disease, save lives, and be cost saving compared with SC.

Cost-utility of 20-valent pneumococcal conjugate vaccine compared to no vaccination and recommended alternative vaccines among Belgian adults

BACKGROUND

The Belgian Superior Health Council (SHC) preferentially recommended the 20-valent pneumococcal conjugate vaccine (PCV20) for adults aged ≥65 years, immunocompromised patients, and patients aged ≥50 years suffering from conditions that increase their risk for pneumococcal infections. The objective of this paper is to present the cost-utility of PCV20 compared to no vaccination and the alternative sequence of PCV15 followed by the 23-valent pneumococcal polysaccharide vaccine (PPV23) in this population.

RESEARCH DESIGN AND METHODS

The analysis employed a static Markov model capturing lifetime risk of pneumococcal infections, associated disutility, mortality, and costs from different healthcare payer perspectives.

RESULTS

Results indicated use of PCV20 among Belgian older and at-risk adults is highly cost-effective compared to no vaccination, with an incremental cost per quality-adjusted life-year (QALY) of €4,164. Compared to the sequential regimen (PCV15+PPV23), PCV20 vaccination is a cost-saving strategy. Subgroup analysis indicated PCV20 vaccination of at-risk adults aged 65-84 years would also be cost-saving from the national healthcare perspective.

CONCLUSION

Based on current knowledge, this analysis suggests that access to PCV20 should be proposed in all adults recommended for vaccination by the SHC as PCV20 prevents additional hospitalizations and deaths caused by pneumococcal infection at an affordable cost.

A review of evidence for pneumococcal vaccination in adults at increased risk of pneumococcal disease: risk group definitions and optimization of vaccination coverage in the United Kingdom

INTRODUCTION

Pneumococcal disease (PD) significantly contributes to morbidity and mortality, carrying substantial economic and public health burden. This article is a targeted review of evidence for pneumococcal vaccination in the UK, the definitions of groups at particular risk of PD and vaccine effectiveness.

AREAS COVERED

Relevant evidence focusing on UK data from surveillance systems, randomized controlled trials, observational studies and publicly available government documents is collated and reviewed. Selected global data are included where appropriate.

EXPERT OPINION

National vaccination programs have reduced the incidence of vaccine-type PD, despite the rising prominence of non-vaccine serotypes in the UK. The introduction of higher-valency conjugate vaccines provides an opportunity to improve protection against PD for adults in risk groups. Several incentives are in place to encourage general practitioners to vaccinate risk groups, but uptake is low-suboptimal particularly among at-risk individuals. Wider awareness and understanding among the public and healthcare professionals may increase vaccination uptake and coverage. National strategies targeting organizational factors are urgently needed to achieve optimal access to vaccines. Finally, identifying new risk factors and approaches to risk assessment for PD are crucial to ensure those at risk of PD can benefit from pneumococcal vaccination.

To the question of the relevance of the development and prospects for the use of the bacteriophage <i>Streptococcus pneumoniae</i>

Introduction. The prevalence of Streptococcus pneumoniae strains causing invasive forms of pneumococcal infection and the growing rates of antibiotic resistance of individual serotypes of the pathogen pose a number of urgent and socially significant tasks the search for new antimicrobial agents for prevention and treatment. Objective. To analyze the data of scientific publications of domestic and foreign authors on the problems of practical use and prospects for the development of the bacteriophage S. pneumoniae drug aimed at the actual serotypes of the pathogen. Results. Analysis of literary sources in scientific electronic databases and publishing houses eLibrary.Ru, ScienceDirect, Scopus, PubMed, Springerlink, Wiley Online Library, Annual reviews allowed us to summarize information about four isolated lytic bacteriophages of S. pneumoniae and their endolysins, as well as about two lysogenic phages, to present data on the clinical efficacy of streptococcal bacteriophage in pneumococcal infection in animals and humans. The results of search queries on the most significant and widespread serotypes of S. pneumoniae in the territory of the Russian Federation have established the predominance in the structure of variants 19F, 14, 9V/A, 15 A/F, 6 A/B/C/D, 3 and 23F. Some of them are characterized by a high level of antibiotic resistance and cause invasive forms of the disease, and serotypes 15 A/F/C, 6 C/D are not represented in modern vaccines, which increases the relevance of the development and use of pneumococcal bacteriophage, including intraspecific typing of significant and common serotypes. Conclusion. Based on the analysis of the current state of the issue of pneumococcal bacteriophages, the information obtained on the circulation of topical strains of S. pneumoniae on the territory of the Russian Federation and their serotype landscape, it is concluded that the development of the bacteriophage S. pneumoniae drug is relevant as a means of targeted action for the prevention, diagnosis and personalized therapy of human diseases of pneumococcal etiology.

Building on a Strong Foundation to Address a New Era to Help Protect Against Pneumococcal Disease

Antoni Torres, Respiratory Intensive Care Unit, Department of Pneumology and Respiratory Allergy, Hospital Clinic of Barcelona, University of Barcelona, Spain, opened the symposium, noting that pneumococcal conjugate vaccines (PCV) have reduced pneumococcal disease through direct and indirect effects. However, the burden of pneumococcal disease remains substantial in adults, supporting the importance of further reducing vaccine-preventable disease and its impact on healthcare resource utilisation and public health. Mário Ramirez, Faculty of Medicine, University of Lisbon, Portugal, and Molecular Microbiology and Infection Laboratory, Institute of Molecular Medicine, University of Lisbon, Portugal, reviewed the changing serotype epidemiology of pneumococcal disease in Europe, and described important differences between pneumococcal polysaccharide vaccines and PCVs. He detailed the dramatic direct impact of PCVs in children in decreasing the burden of vaccine-type (VT) pneumococcal disease, as well as indirect effects in unvaccinated populations, particularly adults. Residual VT-disease and increases in non-PCV13 disease underscore the need for additional disease coverage that may be afforded by higher-valent PCVs. Charles Feldman, Department of Internal Medicine, University of the Witwatersrand, Johannesburg, South Africa, reviewed the considerable worldwide burden of lower respiratory tract infections (LRTI), including pneumococcal pneumonia. He noted that indirect effects in adults may be suboptimal, and herd effects may have reached their limit. Feldman described adult populations that should be prioritised for pneumococcal vaccination based on risk factors, and stressed the importance of a comprehensive approach to increase adult vaccination. Finally, Wendy Watson, Vaccines Clinical Research, Pfizer, Collegeville, USA, described the adult PCV20 clinical development programme, emphasising that it was built on the well-established PCV13 platform. In the Phase III clinical trial programme, PCV20 was well tolerated, with a safety profile similar to PCV13, regardless of prior pneumococcal vaccination history. Importantly, it was immunogenic across all ages studied and in those with chronic medical conditions. Wendy Watson concluded that PCV20 has the potential to simplify adult vaccination and help reduce the burden of adult pneumococcal disease.

Cost-effectiveness of using a 20-valent pneumococcal conjugate vaccine to directly protect adults in England at elevated risk of pneumococcal disease

OBJECTIVES

Despite the current pneumococcal vaccination program in England for older adults and adults with underlying conditions, disease burden remains high. We evaluated cost-effectiveness of 20-valent pneumococcal conjugate vaccine (PCV20) compared to current pneumococcal recommendations for adults in England.

METHODS

Lifetime outcomes/costs of invasive pneumococcal disease (IPD) and community-acquired pneumonia (CAP) among adults aged 65-99 years and adults aged 18-64 years with underlying conditions in England were projected using a probabilistic cohort model. Vaccination with PCV20 was compared with 23-valent pneumococcal polysaccharide vaccine (PPV23) from the National Health Service perspective.

RESULTS

PCV20 was cost saving compared with PPV23 in base case and most sensitivity analyses. In the base case, replacing PPV23 with PCV20 prevented 7,789 and 140,046 cases of IPD and hospitalized CAP, respectively, and 22,199 associated deaths, resulting in incremental gain of 91,375 quality-adjusted life-years (QALYs) and incremental savings of £160M. In probabilistic sensitivity analyses, PCV20 (vs. PPV23) was cost saving in 85% of simulations; incremental cost per QALY was below £30,000 in 99% of simulations.

CONCLUSIONS

PCV20 vaccination in adults aged 65-99 years and those aged 18-64 years with underlying comorbidities in England is expected to prevent more hospitalizations, save more lives, and yield lower overall costs than current recommendations for PPV23.

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.

Public health and budgetary impact of 20-valent pneumococcal conjugate vaccine for adults in England

BACKGROUND

. Despite use of 23-valent pneumococcal polysaccharide vaccine (PPV23) in England, disease burden among at-risk adults remains high. We evaluated the public health and budgetary impact of 20-valent pneumococcal conjugate vaccine (PCV20) compared to the current adult pneumococcal vaccination program.

METHODS

Five-year outcomes and costs of invasive pneumococcal disease (IPD) and community-acquired pneumonia (CAP) among adults aged 65-99 years and adults aged 18-64 years with underlying conditions in England were projected using a deterministic cohort model. Hypothetical vaccination with PCV20 versus PPV23 was compared from National Health Service (NHS) perspective.

RESULTS

Replacing PPV23 with PCV20 would prevent 785 IPD hospitalizations, 11,751 CAP hospitalizations, and 1,414 deaths over five years, and would reduce medical care costs by £48.5M. With vaccination costs higher by £107.2M, projected net budgetary impact is £58.7M. The budgetary impact would be greatest in year one (£26.3M), and would decrease over time (to £1.6M by year five). The average budget increase (£11.7M/year) represents <0.01% of the Department of Health and Social Care budget and <3% of the vaccines budget.

CONCLUSIONS

Use of PCV20 among adults currently eligible for PPV23 in England would substantially reduce the burden of pneumococcal disease, with modest budgetary impact.

Pneumococcal meningitis in Greece: A retrospective serotype surveillance study in the post-PCV13 era (2010-2020)

BACKGROUND

As Greece is a country which has introduced the 13-valent pneumococcal conjugate vaccine (PCV13) both in the infant and in the adult immunization programs, the aim of the study was to investigate age-specific and serotype-specific trends of pneumococcal meningitis over an 11-year period (2010-2020).

MATERIALS AND METHODS

Data are reported from pneumococcal meningitis cases [notified to the National Public Health Organization (NPHO)], with clinical samples and bacterial isolates sent for pneumococcal identification and serotyping at the National Meningitis Reference Laboratory (NMRL). Pneumococcal identification was performed directly on clinical samples or bacterial isolates by multiplex PCR (mPCR) assay, while serotyping was carried out by application of the Capsular Sequence Typing (CST) method with the combination of single tube PCR assays.

RESULTS

A total of 427 pneumococcal meningitis cases were notified to the NPHO between 2010 and 2020. Among those, 405 (94.8%) were microbiologically confirmed, while samples from 273 patients were sent to the NMRL for identification and/or further typing. The annual notification rate peaked at 0.47/100,000 in 2016 and since then has been decreasing. The incidence was highest in infants and in older adults. Pneumococcal serotypes were identified in 260/273 (95.2%) cases, where clinical samples were sent to the NMRL. The most prevalent serotypes (≥5%) were 3, 19A, 23B, 15B/C, 11A/D, 23A, 22F. During the study period there has been a decrease of PCV13 serotypes combined with an increase of non-PCV13 serotypes (p = 0.0045).

CONCLUSIONS

This is the first study to report serotypes for pneumococcal meningitis across all ages in the post-PCV13 era in Greece. There is a need to enhance surveillance, by close monitoring of the emerging serotypes and the impact of vaccination programs. Higher-valency PCVs may help to improve the coverage of pneumococcal disease.

Missed Opportunities? A retrospective study into adults hospitalized with invasive infection from airway pathogens

Background

Invasive disease caused by airway pathogens, including Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, and Moraxella catarrhalis, has high morbidity and mortality worldwide, with immunodeficiency being a known association with recurrent disease. The study aimed to describe the frequency of known immunodeficiency and predisposing factors in adult patients presenting with invasive infections and determine the frequency of screening for and detection of immunodeficiency.

Methods

A retrospective analysis was conducted at a large tertiary Australian health service, comprising multiple centers. Patients aged 18 years or older, in whom the above pathogens were isolated from sterile sites, were included as identified through a microbiology database, between 2015 and 2020. Using electronic medical records, patient demographics, medical history, outcomes of admission, and pathology results were captured and reviewed to address the aims.

Results

In 252 patients, S pneumoniae was the most common culprit, isolated in 73% (185/252), compared to 14.3% (36/252) and 11.5% (29/252) of infections caused by H influenzae and N meningitidis, respectively. Known diagnoses of secondary immunodeficiency were common (31% of patients). Of those presenting with invasive pneumococcal disease, 78% had at least 1 predisposing condition, though only 9 patients (6%) had previously received pneumococcal vaccination. Despite poor screening for immunodeficiency, 12 new diagnoses were made. While the commonest immunodeficiency was secondary, due to hematological and solid organ malignancies, 3 new primary immunodeficiency diagnoses were made.

Conclusions

Immunodeficiency is common in this patient population. Screening should be undertaken to ensure timely diagnosis and treatment of the underlying condition to avoid future morbidity and mortality.

Effectiveness of 7-Valent Pneumococcal Conjugate Vaccine Against Invasive Pneumococcal Disease in Medically At-Risk Children in Australia: A Record Linkage Study

BACKGROUND

Children with chronic medical conditions are at higher risk of invasive pneumococcal disease (IPD), but little is known about the effectiveness of the primary course of pneumococcal conjugate vaccine (PCV) in these children.

METHODS

A cohort born in 2001-2004 from two Australian states and identified as medically at-risk (MAR) of IPD either using ICD-coded hospitalizations (with conditions of interest identified by 6 months of age) or linked perinatal data (for prematurity) were followed to age 5 years for notified IPD by serotype. We categorized fully vaccinated children as either receiving PCV dose 3 by <12 months of age or ≥1 PCV dose at ≥12 months of age. Cox proportional hazard modeling was used to estimate hazard ratios (HRs), adjusted for confounders, and vaccine effectiveness (VE) was estimated as (1-HR) × 100.

RESULTS

A total of 9220 children with MAR conditions had 53 episodes of IPD (43 vaccine-type); 4457 (48.3%) were unvaccinated and 4246 (46.1%) were fully vaccinated, with 1371 (32.3%) receiving dose 3 by 12 months and 2875 (67.7%) having ≥1 dose at ≥12 months. Estimated VE in fully vaccinated children was 85.9% (95% CI: 33.9-97.0) against vaccine-type IPD and 71.5% (95% CI: 26.6-88.9) against all-cause IPD.

CONCLUSION

This is the first population-based study evaluating the effectiveness of PCV in children with MAR conditions using record linkage. Our study provides evidence that the VE for vaccine-type and all-cause IPD in MAR children in Australia is high and not statistically different from previously reported estimates for the general population. This method can be replicated in other countries to evaluate VE in MAR children.

Improving Pneumococcal Vaccination Rates in High-risk Children in Specialty Clinics

BACKGROUND AND OBJECTIVES

Pediatric patients with immunocompromising or certain chronic medical conditions have an increased risk of acquiring invasive pneumococcal disease (IPD). The 23-valent pneumococcal polysaccharide vaccine (PPSV23) is recommended for patients ≥2 years at high risk for IPDs. The aim of this project was to improve PPSV23 vaccination rates for children at high risk for IPD who were seen in 3 specialty clinics from ∼20% to 50% over a 12-month period.

METHODS

The project team included quality improvement champions from the divisions of rheumatology, infectious diseases, and pulmonology in addition to leaders from our population health management subsidiary. Several initiatives were implemented, starting with review of patient inclusion criteria per the vaccination recommendations, that led to the design and deployment of an automated weekly previsit planning report. Additionally, we implemented a process to stock pneumococcal vaccines and shared best practices among the divisions. We monitored improvement through times series and run charts of PPSV23 vaccination rates.

RESULTS

The initial PPSV23 vaccination rate for applicable high-risk patients was ∼20%. There was an increase in vaccination rate to ∼60%. All 3 divisions showed improvements in their individual PPSV23 vaccination rates.

CONCLUSIONS

Using quality improvement methodology, we increased PPSV23 vaccination rates in 3 pediatric specialty clinics, and this improvement was sustained. We will continue to identify best practices and actively recruit additional divisions because we have the opportunity to reach >9000 high-risk patients.

Cost-effectiveness of the 15-valent pneumococcal conjugate vaccine for high-risk adults in Switzerland

BACKGROUND

: Vaccination against pneumococcal disease (PD) has shown a favourable cost-effectiveness profile for national immunization programs in multiple countries. While vaccination efforts have concentrated on children, many adults with underlying illnesses face elevated risks of PD and death. A 15-valent pneumococcal conjugate vaccine (V114) is currently available that offers protection against 15 different serotypes and can be used in adults.

RESEARCH DESIGN AND METHODS

: We examined the cost-effectiveness of V114 vaccination in high-risk adults, aged 18+, in Switzerland. To this end, a Markov model was constructed estimating the lifetime direct medical costs and clinical effectiveness of V114 vaccination on invasive pneumococcal disease (IPD) and non-bacteremic pneumococcal pneumonia (NBPP) among high-risk adults.

RESULTS

: Considering 60% vaccine uptake and direct effects of vaccination, in total 760 IPD and 4,396 NBPP in- and outpatient cases could be prevented. Vaccinating high-risk adults with V114 led to CHF 37.4 million additional vaccination costs but saved CHF 14.4 million of medical treatment costs. V114 vaccination produced a gain of 2,095 QALYs and 6,320 LYs compared with no vaccination, leading to incremental cost-effectiveness ratios of CHF 17,866/QALY and CHF 15,616/QALY gained from a health care payer and societal perspective, respectively.

Conclusions: This evidence justifies the implementation of V114 vaccination among high-risk adults in Switzerland.

Pneumococcal Vaccination Coverage and Uptake Among Adults in Switzerland: A Nationwide Cross-Sectional Study of Vaccination Records

Streptococcus pneumoniae, or pneumococcus, is a common, opportunistic pathogen which can cause severe disease, particularly in adults 65+. In Switzerland, vaccination is recommended for children under 5 and for adults with health predispositions; vaccination of healthy adults 65+ is not recommended. In 2020 we conducted a nationwide, cross-sectional survey of vaccination records to evaluate pneumococcal vaccination coverage and factors affecting uptake among adults 18–85. We found that nationwide coverage was 4.5% without significant regional differences. Coverage was comparable between men and women and between those aged 18–39 (3.0%) and 40–64 (3.2%). Coverage was significantly higher among those 65–85 (9.6%). While 2.7% of individuals reporting no health predisposition were vaccinated, 14.8% with asthma or chronic pulmonary disease, 27.1% with immunosuppression, 12.9% with diabetes, 11.6% with heart, liver, or kidney disease, and 25.9% with >1 health risk were vaccinated. Adjusted odds of vaccination for all health predispositions except heart, liver, or kidney disease were significantly increased. Among unvaccinated individuals “not enough information about the topic” and “not suggested by a doctor/healthcare provider” were the major reasons for abstaining from vaccination. Respondents reporting a health predisposition were significantly less likely to report “not at increased risk due to chronic health conditions or age” as a reason for not being vaccinated (3.7% vs. 29.1%) and were more likely to report willingness to be vaccinated in the future compared to those not-at-risk (54.2% vs. 39.9%). Our results indicate that pneumococcal vaccination coverage in Switzerland is low among both individuals 65–85 and among those with predisposing health risks. It appears that at-risk individuals are aware of their increased risk, but feel they do not have enough information on the topic to seek vaccination, or have not been recommended a vaccination by their physician.

PCV13 Vaccination of Adults against Pneumococcal Disease: What We Have Learned from the Community-Acquired Pneumonia Immunization Trial in Adults (CAPiTA)

The Community-Acquired Pneumonia immunization Trial in Adults (CAPiTA) evaluated older adult pneumococcal vaccination and was one of the largest vaccine clinical trials ever conducted. Among older adults aged ≥65 years, the trial established 13-valent pneumococcal conjugate vaccine (PCV13) efficacy in preventing first episodes of bacteremic and nonbacteremic pneumococcal vaccine serotype (VT) community acquired pneumonia (CAP), and of vaccine serotype invasive pneumococcal disease (VT-IPD). Since the publication of the original trial results, 15 additional publications have extended the analyses. In this review, we summarize and integrate the full body of evidence generated by these studies, contextualize the results in light of their public health relevance, and discuss their implications for the assessment of current and future adult pneumococcal vaccination. This accumulating evidence has helped to better understand PCV13 efficacy, serotype-specific efficacy, efficacy in subgroups, the interpretation of immunogenicity data, and the public health value of adult PCV vaccination.

Risk factors for pneumococcal disease in persons with chronic medical conditions: Results from the LIFE Study

OBJECTIVES

This study aimed to identify the risk factors for pneumococcal disease.

METHODS

The study was performed using insurance claims data from the residents of 12 Japanese municipalities. Based on recorded diagnoses, we identified chronic medical conditions in each patient between April 2015 and March 2016 and examined the subsequent occurrence of a pneumococcal disease from April 2016 onward. Cox proportional hazards models were used to estimate the hazard ratio of each chronic medical condition for a pneumococcal disease occurrence.

RESULTS

The study was conducted on 732,235 patients, of whom, 61,306 (8.4%) were aged 0-18 years, 184,367 (25.2%) were aged 19-49 years, 126,078 (17.2%) were aged 50-64 years, and 360,484 (49.2%) were aged ≥65 years. A higher number of conditions was associated with a higher incidence of pneumococcal disease. Significant risk factors for pneumococcal disease in all patients included chronic heart disease, chronic lung disease, diabetes mellitus, cancer, and chronic renal disease. Furthermore, chronic lung disease, diabetes mellitus, aspiration pneumonia, and immunosuppressant use were risk factors among patients aged 50-64 years.

CONCLUSIONS

Persons aged 50-64 years with multiple chronic medical conditions or with specific conditions are at a higher risk of developing pneumococcal disease, indicating a need to consider their inclusion in routine vaccination programs.

Cost-effectiveness of 20-valent pneumococcal conjugate vaccine in Denmark compared with PPV23

BACKGROUND

A new 20-valent pneumococcal conjugate vaccine (PCV20) provides protection against 20 pneumococcal serotypes. The vaccine has the potential to decrease the impact of pneumococcal diseases in society and to increase health among vulnerable persons.

AIM

This study investigates the cost-effectiveness of vaccinating Danish adults in different age groups and risk of pneumococcal disease with PCV20 compared to the 23-valent pneumococcal polysaccharide vaccine (PPV23) - either as PCV20 compared to PPV23 or as PPV23 followed by PCV20 compared to PPV23.

METHODS

A Markov model adapted to the Danish setting was developed to estimate clinical outcomes and costs of vaccinating the Danish population in specific age and risk groups. The model used a restricted societal perspective and estimated outcomes and costs using a lifetime time horizon. To estimate the clinical outcomes and costs, inputs on vaccine effectiveness and waning were retrieved from other studies whereas data on risk groups, coverage and costs were based on real-world data.

RESULTS

The results showed that in all scenarios the incidence and mortality of pneumococcal disease were reduced when vaccinating with PCV20, resulting in lower costs. For the vaccine target group of adults aged ≥18 years at moderate or high risk and all adults aged ≥65 years both in the case of PPV23+PCV20 compared to PPV23 and in case of PCV20 compared to PPV23 vaccination with PCV20 was found to be a dominant strategy gaining 1,350 or 5,821 quality-adjusted life years (QALYs), respectively, and reducing total costs by 60 or 396 million EUR, respectively, as compared to PPV23 vaccination alone. Similar results of dominant PCV20 strategy were found for other age and risk group comparisons. Both deterministic and probabilistic sensitivity analyses confirmed the results being robust to changes in input parameters and applied assumptions.

LIMITATIONS

Like other modelling studies, this analysis has limitations such as lack of detailed data for some inputs.

CONCLUSION

Vaccination with PCV20 reduced the incidence and mortality of pneumococcal diseases in Danish adults compared to PPV23. This reduction has the potential to reduce the financial burden related to managing diseases while also increasing public health.

Comparative characteristics of the background and blood test findings in adults with pneumococcal pneumonia and invasive pneumococcal disease: A retrospective study

INTRODUCTION

Invasive pneumococcal disease (IPD) is often fatal, requiring prompt diagnosis and treatment. To evaluate the factors associated with IPD in adults, we retrospectively investigated its characteristics compared to pneumococcal pneumonia without confirmation of invasion (PP).

METHODS

Patients >18 years with PP (n = 79) and IPD (n = 53) from whom Streptococcus pneumoniae was isolated were enrolled from two hospitals between 2011 and 2017. Clinical backgrounds, blood test results at admission, initial antimicrobials administered, isolate serotypes, and outcomes were compared between the PP and IPD groups.

RESULTS

Patients with IPD exhibited higher mortality (28.3%) than those with PP (2.5%) (p<0.001), regardless of the type of antimicrobials first administered. The majority (80.0%) of fatal cases of IPD were due to vaccine serotypes. Almost all patients with PP (97.4%) and IPD (88.7%) had underlying disease. C-reactive protein (CRP) ≥17.0 mg/dL (odds ratio [OR], 7.1; 95% CI, 2.7-19.0; p<0.001), white blood cell counts <11.0 × 10³/μL (OR, 3.2; 95% CI, 1.3-8.4; p = 0.016), and platelet (PLT) counts <16.2 × 10⁴/μL (OR, 2.8; 95% CI, 1.1-7.4; p = 0.036) were significantly more common in IPD. Moreover, 89.5% of cases with both CRP ≥23.8 mg/dL and PLT <18.5 × 10⁴/μL were diagnosed with IPD.

CONCLUSION

Laboratory blood test findings at admission, particularly high CRP and low PLT values, are useful early indicators of IPD in adults. These results could be used to initiate rapid and intensive treatment and improve prognosis.

[Vaccinations]

Vaccination is considered one of the most important achievements of modern medicine and has saved millions of lives. As a result, the age-old fear of severe or fatal infectious diseases has largely been forgotten in society; however, the pandemic triggered by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) shows how quickly this fear can return. Also, many people have reservations about medical measures, especially if they are directed against vague dangers. Paradoxically, the success of vaccinations jeopardizes the acceptance. To counteract this development, this article provides information on basic vaccination principles, legal frameworks and components of vaccines. It explains the most important categories, goals, core elements of vaccination programs and the most important recommendations of the Standing Committee on Vaccination at the Robert Koch Institute (STIKO). It explains the current state of knowledge with respect to required resources, assessment of vaccine reactions, complication management and possible vaccine damage.

Pneumococcal Immunization Strategies for High-Risk Pediatric Populations Worldwide: One Size Does Not Fit All

Despite the significant reduction in pneumococcal disease due to pneumococcal vaccines, protection of vulnerable high-risk individuals, especially pediatric populations, remains a great challenge. In an effort to maximize the protection of high-risk children against pneumococcal disease, a combined schedule that includes both conjugate and polysaccharide vaccines is recommended by several countries in the developed world. On the other hand, middle- and low-income countries do not have in place established policies for pneumococcal immunization of children at risk. Pneumococcal conjugate vaccines, despite their benefits, have several limitations, mainly associated with serotype replacement and the wide range of serotype coverage worldwide. In addition, PPV23-impaired immunogenicity and the hyporesponsiveness effect among populations at risk have been well-documented. Therefore, the added value of continuing to include PPV23 in vaccination schedules for high-risk individuals in the years to come remains to be determined by monitoring whether the replacing/remaining serotypes causing IPD are covered by PPV23 to determine whether its benefits outweigh its limitations. In this review, we aim to describe serotype distribution and vaccine efficacy data on pneumococcal disease in the pre- and post-PCV implementation era among high-risk children in both developed and developing countries, assessing the optimization of current recommendations for their vaccination against pneumococcal disease.

Cross-sectional study on the prevalence of influenza and pneumococcal vaccination and its association with health conditions and risk factors among hospitalized multimorbid older patients

BACKGROUND

Older adults with chronic conditions are at high risk of complications from influenza and pneumococcal infections. Evidence about factors associated with influenza and pneumococcal vaccination among older multimorbid persons in Europe is limited. The aim of this study was to investigate the prevalence and determinants of these vaccinations in this population.

METHODS

Multimorbid patients aged ≥70 years with polypharmacy were enrolled in 4 European centers in Switzerland, Belgium, the Netherlands, and Ireland. Data on vaccinations, demographics, health care contacts, and comorbidities were obtained from self-report, general practitioners and medical records. The association of comorbidities or medical contacts with vaccination status was assessed using multivariable adjusted log-binomial regression models.

RESULTS

Among 1956 participants with available influenza vaccination data (median age 79 years, 45% women), 1314 (67%) received an influenza vaccination within the last year. Of 1400 patients with available pneumococcal vaccination data (median age 79 years, 46% women), prevalence of pneumococcal vaccination was 21% (n = 291). The prevalence of vaccination remained low in high-risk populations with chronic respiratory disease (34%) or diabetes (24%), but increased with an increasing number of outpatient medical contacts. Chronic respiratory disease was independently associated with the receipt of both influenza and pneumococcal vaccinations (prevalence ratio [PR] 1.09, 95% confidence interval [CI] 1.03-1.16; and PR 2.03, 95%CI 1.22-3.40, respectively), as was diabetes (PR 1.06, 95%CI 1.03-1.08; PR 1.24, 95%CI 1.16-1.34, respectively). An independent association was found between number of general practitioner visits and higher prevalence of pneumococcal vaccination (p for linear trend <0.001).

CONCLUSION

Uptake of influenza and particularly of pneumococcal vaccination in this population of European multimorbid older inpatients remains insufficient and is determined by comorbidities and number and type of health care contacts, especially outpatient medical visits. Hospitalization may be an opportunity to promote vaccination, particularly targeting patients with few outpatient physician contacts.

Recommendations of the Italian society for infectious and tropical diseases (SIMIT) for adult vaccinations

Vaccination prevents 2-3 million deaths worldwide every year. Nevertheless, vaccine-preventable diseases (VPDs) still cause a considerable number of deaths especially in subjects belonging to "risk groups." These are represented by older adults, immunocompromised individuals and all subjects with underlying chronic medical conditions (cardiovascular, pulmonary, renal and liver chronic diseases, diabetes, immunodeficiency disorders). They have a weaker immune system and, if infected, are more likely to develop severe complications of their condition or of the preventable-infectious disease. This document summarizes the recommendations for vaccination of the main Global Institutional Organizations and analyses the risks of comorbidities associated with infectious disease and the benefits of vaccination for each specific group. The document provides a clear, practical and authoritative guide to adult vaccination.

A review of current data to support decision making for introduction of next generation higher valency pneumococcal conjugate vaccination of immunocompetent older adults in the UK

INTRODUCTION

The burden of pneumococcal disease in older UK adults remains substantial. Higher valency pneumococcal conjugate vaccines (PCVs) are currently in development with adult formulations for two of these anticipated to become available in 2022. This article collates and reviews relevant candidate data now available that may be used to support cost effectiveness assessments of vaccinating immunocompetent UK adults aged ≥65-years with PCVs.

AREAS COVERED

This article uses published data from surveillance systems, randomized controlled trials and observational studies. It focuses on local data from the UK but where these are either limited or not available relevant global data are considered.

EXPERT OPINION

The body of relevant data now available suggests the UK is well placed to assess the cost effectiveness of vaccinating immunocompetent ≥65-year olds with new generation higher valency PCVs. Recent contemporary data provide important new and robust insights into the epidemiology of pneumococcal disease in older UK adults and help to address much of the uncertainty and data gaps associated with previous analyses. Using these data to make informed decisions about use of new higher valency PCVs for routine use in older adults will be important for public health in the UK.

Understanding the Host in the Management of Pneumonia. An Official American Thoracic Society Workshop Report

Pneumonia causes a significant burden of disease worldwide. Although all populations are at risk of pneumonia, those at extremes of age and those with immunosuppressive disorders, underlying respiratory disease, and critical illness are particularly vulnerable. Although clinical practice guidelines addressing the management and treatment of pneumonia exist, few of the supporting studies focus on the crucial contributions of the host in pneumonia pathogenesis and recovery. Such essential considerations include the host risk factors that lead to susceptibility to lung infections; biomarkers reflecting the host response and the means to pursue host-directed pneumonia therapy; systemic effects of pneumonia on the host; and long-term health outcomes after pneumonia. To address these gaps, the Pneumonia Working Group of the Assembly on Pulmonary Infection and Tuberculosis led a workshop held at the American Thoracic Society meeting in May 2018 with overarching objectives to foster attention, stimulate research, and promote funding for short-term and long-term investigations into the host contributions to pneumonia. The workshop involved participants from various disciplines with expertise in lung infection, pneumonia, sepsis, immunocompromised patients, translational biology, data science, genomics, systems biology, and clinical trials. This workshop report summarizes the presentations and discussions and important recommendations for future clinical pneumonia studies. These recommendations include establishing consensus disease and outcome definitions, improved phenotyping, development of clinical study networks, standardized data and biospecimen collection and protocols, and development of innovative trial designs.

The Risk of Invasive Pneumococcal Disease Differs between Risk Groups in Norway Following Widespread Use of the 13-Valent Pneumococcal Vaccine in Children

The elderly and adults with medical risk conditions remain at high risk of invasive pneumococcal disease (IPD), highlighting the importance of adequate preventive efforts. In an observational population-based study in Norway (pop ≥ 5 years, 2009-2017) covering six years post-PCV13 implementation, we explored the incidence and risk of IPD associated with age and comorbidities. We obtained the data on 5535 IPD cases from the Norwegian Surveillance System for Communicable Diseases and the population data from Statistics Norway. To define comorbidities, we obtained ICD-10 codes from the Norwegian Patient Registry for the cases and the Norwegian population. The average annual decrease in PCV13 IPD incidence was significant in all risk groups and decreased post-PCV13 introduction by 16-20% per risk group, implying a nondifferential indirect protection from the childhood vaccination. The IPD incidence remained high in the medical risk groups. The relative importance of medical risk conditions was 2.8 to 6 times higher in those aged 5-64 versus ≥65 years for all types of IPD, since age itself is a risk factor for IPD. In groups without medical risk, the risk of IPD was eight times higher in those aged ≥65 compared to those 5-64 years (RR 8.3 (95% CI 7.3-9.5)). Our results underscore the need for age- and risk-group-based prevention strategies.

American Association for the Study of Liver Diseases Expert Panel Consensus Statement: Vaccines to Prevent Coronavirus Disease 2019 Infection in Patients With Liver Disease

The aim of this document is to provide a concise scientific review of the currently available COVID-19 vaccines and those in development, including mRNA, adenoviral vectors, and recombinant protein approaches. The anticipated use of COVID-19 vaccines in patients with chronic liver disease (CLD) and liver transplant (LT) recipients is reviewed and practical guidance is provided for health care providers involved in the care of patients with liver disease and LT about vaccine prioritization and administration. The Pfizer and Moderna mRNA COVID-19 vaccines are associated with a 94%-95% vaccine efficacy compared to placebo against COVID-19. Local site reactions of pain and tenderness were reported in 70%-90% of clinical trial participants, and systemic reactions of fever and fatigue were reported in 40%-70% of participants, but these reactions were generally mild and self-limited and occurred more frequently in younger persons. Severe hypersensitivity reactions related to the mRNA COVID-19 vaccines are rare and more commonly observed in women and persons with a history of previous drug reactions for unclear reasons. Because patients with advanced liver disease and immunosuppressed patients were excluded from the vaccine licensing trials, additional data regarding the safety and efficacy of COVID-19 vaccines are eagerly awaited in these and other subgroups. Remarkably safe and highly effective mRNA COVID-19 vaccines are now available for widespread use and should be given to all adult patients with CLD and LT recipients. The online companion document located at https://www.aasld.org/about-aasld/covid-19-resources will be updated as additional data become available regarding the safety and efficacy of other COVID-19 vaccines in development.

Chronic disease and immunosuppression increase the risk for non-vaccine serotype pneumococcal disease - a nationwide population-based study

Background

Demography is changing, with people living longer with comorbidities. In this nationwide population-based study, we investigated the serotype-specific invasive pneumococcal disease (IPD) risk in individuals with comorbidities, and effects of the pneumococcal conjugated vaccine (PCV) child immunization program.

Methods

Cases included 14 096 IPD episodes in Sweden during 2006–2015. Controls (n = 137 289), matched to cases by age, sex, region, and calendar time, were selected from the general population. Comorbidity data was obtained through health registers and grouped as immunocompromising (IC) or chronic medical conditions (CMC).

Results

The prevalence of CMC and IC among elderly cases was 33.9% and 39.4%. New risks identified for IPD were sarcoidosis, inflammatory polyarthropathies, systemic connective tissue, and neurological diseases. The odds ratio (OR) for IPD caused by non-PCV13 compared with PCV13 serotypes was higher in individuals with CMC/IC. Serotypes associated with the highest risk were 16F, 15C, 35F, 19F, and 23A (OR 3–5 for CMC, >10 for IC). Most comorbidities increased post-vaccination, and absolute increases of IPD caused by non-PCV13, PPV23–non-PCV13, and non-PCV13/non-PPV23 serotypes were higher in individuals with IC/CMC compared with healthy persons. Non-PCV13 serotypes 6C, 9N, 11A, 22F, 23A and 35F increased more in those with comorbidities. Mortality due to non-PCV13 serotypes increased in individuals with IC/CMC, while remaining stable in persons without comorbidities.

Conclusions

The PCV child immunization program associates with an increased disease burden of non-vaccine serotypes in individuals with comorbidities. These data are important for vaccine design and optimization of current vaccination strategies.

Development of a pneumococcal conjugate vaccine based on chemical conjugation of polysaccharide serotype 6B to PspA

The use of conjugate vaccines remains an effective intervention to prevent pneumococcal diseases. In order to expand vaccine coverage, the inclusion of pneumococcal proteins as carriers is a propitious alternative that has been explored over the past few years. In this study, pneumococcal surface protein A (PspA) clade 1, family 1 (PspA1) and clade 3, family 2 (PspA3) were used as carrier proteins for pneumococcal capsular polysaccharide serotype 6B (Ps6B). Employing an improved reductive amination chemistry, 50% of Ps6B was incorporated to each protein, PspA1 and PspA3. The effect of chemical modifications in Ps6B and PspA was assessed by an antigenicity assay and circular dichroism, respectively. Fragmentation and oxidation decreased the antigenicity of Ps6B while conjugation improved antigenicity. In the same manner, introduction of adipic acid dihydrazide (ADH) reduced PspA secondary structure content, which was partially restored after conjugation. Immunization of Ps6B-PspA1 and Ps6B-PspA3 conjugates in mice induced specific IgG antibodies against the Ps6B and the protein; and anti-PspA antibodies had functional activity against two pneumococcal strains with different serotypes. These results suggest that chemical coupling between Ps6B and PspA did not affect antigenic epitopes and support the further development of PspA as a carrier protein in pneumococcal conjugate vaccines to provide broader protection.

The epidemiologic and biologic basis for classifying older age as a high-risk, immunocompromising condition for pneumococcal vaccine policy

INTRODUCTION

Immunosenescence is a normal biologic process involving deterioration of protective immune responses. Consequently, older adults experience increased risk of infectious diseases, particularly pneumonia, and its leading bacterial cause, Streptococcus pneumoniae. Pneumococcal vaccine recommendations are often limited to adults with specific medical conditions despite similar disease risks among older adults due to immunosenescence.

AREAS COVERED

This article reviews epidemiologic, biologic, and clinical evidence supporting the consideration of older age due to immunosenescence as an immunocompromising condition for the purpose of pneumococcal vaccine policy and the role vaccination can play in healthy aging.

EXPERT OPINION

Epidemiologic and biologic evidence suggest that pneumococcal disease risk increases with age and is comparable for healthy older adults and younger adults with immunocompromising conditions. Because immunocompromising conditions are already indicated for pneumococcal conjugate vaccines (PCVs), a comprehensive public health strategy would also recognize immunosenescence. Moreover, older persons should be vaccinated before reaching the highest risk ages, consistent with the approach for other immunocompromising conditions. To facilitate PCV use among older adults, vaccine technical committees (VTCs) could classify older age as an immunocompromising condition based on the process of immunosenescence. With global aging, VTCs will need to consider immunosenescence and vaccine use during healthy aging.

Invasive Pneumococcal Disease in People With Human Immunodeficiency Virus in England, 1999-2017

BACKGROUND

The 7-valent and 13-valent pneumococcal conjugate vaccines (PCVs) were introduced into the UK childhood immunization program in 2006 and 2010, respectively, with high effectiveness and resulting in both direct and indirect protection. We describe the epidemiology of invasive pneumococcal disease (IPD) in adults with human immunodeficiency virus (HIV) in England following the introduction of both PCVs.

METHODS

Data on a national cohort of people with HIV were linked to confirmed IPD cases in adults aged ≥ 15 years during 1999-2017. Date of HIV infection was estimated using a CD4 slope decline algorithm.

RESULTS

Among 133 994 adults with HIV, 1453 developed IPD during 1999-2017, with 70% (1016/1453) developing IPD ≥ 3 months after their HIV diagnosis. IPD and HIV were codiagnosed within 90 days in 345 (24%) individuals. A missed opportunity for earlier HIV diagnosis was identified in 6% (89/1453), mostly in earlier years. IPD incidence in people with HIV increased from 147/100 000 in 1999 to 284/100 000 in 2007 before declining and stabilizing between 92 and 113/100 000 during 2014-2017. Mean annual IPD incidence was lower among those receiving antiretroviral therapy during 2014-17 (68 vs 720/100 000; incidence rate ratio [IRR] 9.3; 95% confidence interval [CI], 7.3-11.8; P < .001) and was markedly lower in those with a suppressed viral load (50 vs 523/100 000; IRR 10.4; 95% CI, 7.6-14.1; P < .001). The latter group still had 4.5-fold higher (95% CI, 3.8-5.3; P < .001) IPD incidence compared to the general population (11.2/100 000).

CONCLUSIONS

IPD incidence among people with HIV reduced after PCV13 introduction and has remained stable. Adults presenting with IPD should continue to be tested for HIV infection.

Don't forget about the future: The impact of including future costs on the cost-effectiveness of adult pneumococcal conjugate vaccination with PCV13 in the Netherlands

BACKGROUND

When vaccines increase longevity, vaccinated people may experience costs and benefits during added life-years. These future benefits and costs may include increased productivity as well as medical and non-medical costs. Such impacts should be considered in cost-effectiveness analyses (CEA) of vaccines but are often omitted. Here, we illustrate the impact of including future costs on the cost-effectiveness of vaccination against pneumococcus disease. We emphasize the relevance of differentiating cost estimates between risk groups.

METHODS

We updated an existing Dutch CEA of vaccination against pneumococcus disease with the 13-valent pneumococcal conjugate vaccine (PCV13) to include all future medical and non-medical costs. We linked costs by age and risk with survival information and estimates of cases prevented per vaccination strategy based on the original study to calculate the impact of inclusion. Future medical costs were adjusted for relevant risk groups.

RESULTS

For the base-case strategy, the original incremental cost-effectiveness ratio (ICER) of PVC13 was €9,157 per quality adjusted life-year (QALY). Including all future medical costs increased the ICER to €28,540 per QALY. Also including future non-medical costs resulted in an ICER of €45,691 per QALY. The impact of future medical costs varied considerably per risk group and generally increased with age.

DISCUSSION AND CONCLUSION

This study showed a substantial effect of the inclusion of future costs on the ICER of vaccinating with PCV13. Especially when lives of people with underlying health conditions are extended, the impact of future medical costs is large. This inclusion may make vaccination a less attractive option, especially in relation to low thresholds as often applied for prevention. Although this raises important questions, ignoring these real future costs may lead to an inefficient use of healthcare resources. Our results may imply that prices for some vaccines need to be lowered to be cost-effective.

Infectious Respiratory Diseases Decreased during the COVID-19 Pandemic in South Korea

Infectious respiratory diseases are highly contagious and very common, and thus can be considered as one of the leading causes of morbidity and mortality worldwide. We followed up the incidence rates (IRs) of eight infectious respiratory diseases, including chickenpox, measles, pertussis, mumps, invasive pneumococcal disease, scarlet fever, rubella, and meningococcal disease, after COVID-19 mitigation measures were implemented in South Korea, and then compared those with the IRs in the corresponding periods in the previous 3 years. Overall, the IRs of these diseases before and after age- or sex-standardization significantly decreased in the intervention period compared with the pre-intervention periods (p < 0.05 for all eight diseases). However, the difference in the IRs of all eight diseases between the IRs before and after age-standardization was significant (p < 0.05 for all periods), while it was not significant with regard to sex-standardization. The incidence rate ratios for eight diseases in the pre-intervention period compared with the intervention period ranged from 3.1 to 4.1. These results showed the positive effects of the mitigation measures on preventing the development of respiratory infectious diseases, regardless of age or sex, but we need to consider the age-structure of the population to calculate the effect size. In the future, some of these measures could be applied nationwide to prevent the occurrence or to reduce the transmission during outbreaks of these infections. This study provides evidence for strengthening the infectious disease management policies in South Korea.

Incidence of Invasive Pneumococcal Disease Higher Among People Notified With Markers of Hepatitis C Virus Infection: Population-based Surveillance in Victoria, Australia, 2001-2017

BACKGROUND

Worse outcomes from invasive pneumococcal disease (IPD) have been reported among those coinfected with hepatitis C. We aimed to establish if IPD notification rates are higher among people notified with markers of hepatitis C virus infection than the general population.

METHODS

IPD cases notified in Victoria, Australia, from July 2001-December 2017 were linked with hepatitis C cases (diagnosed by serology or PCR testing) notified from January 1991-December 2017. IPD incidence was calculated using population data and the estimated number of Victorians with hepatitis C.

RESULTS

From July 2001-December 2017, 6407 IPD cases were notified. Hepatitis C infection was notified in 342 (5.3%) of IPD cases overall, and 24.4% among IPD cases aged 45-49 years. Among IPD cases also notified with hepatitis C, 55.3% were infected with 13-valent pneumococcal conjugate vaccine serotypes and 82.8% with 23-valent pneumococcal polysaccharide vaccine serotypes. Compared with IPD cases without hepatitis C, IPD cases also notified with hepatitis C were younger (mean age, 45.7 vs 49.4 years; P = .011) and more often male (65.5% vs 55.5%, P < .001). Annual IPD notification incidence was 6.8/100 000 among people without hepatitis C and 39.4/100 000 among people with hepatitis C (IRR, 5.8; 95% CI, 5.2-6.4; P < .001).

CONCLUSIONS

IPD notification incidence was 5 times higher among people notified with markers of hepatitis C than the general population. Pneumococcal vaccination should be offered to people with markers of hepatitis C virus infection. To facilitate appropriate treatment, young and middle-aged adults with IPD should be tested for hepatitis C.

Expanded Analysis of 20 Pneumococcal Serotypes Associated With Radiographically Confirmed Community-Acquired Pneumonia in Hospitalized US Adults

Background

Streptococcus pneumoniae is a causative agent of community-acquired pneumonia (CAP). The 13-valent pneumococcal conjugate vaccine (PCV13) has significantly decreased the burden of PCV13-serotype pneumococcal disease; however, disease from nonvaccine serotypes remains substantial. A recent study documented the persistence of PCV13 serotypes among US adults hospitalized with radiographically confirmed CAP. The current analysis used a recently developed urinary antigen detection (UAD) assay (UAD2) to extend these results to additional serotypes included in an investigational PCV20 vaccine.

Methods

This prospective study enrolled adults aged ≥18 years hospitalized with radiographically confirmed CAP between October 2013 and September 2016. Presence of S pneumoniae was determined by blood and respiratory sample culture, BinaxNOW urine testing, and UAD. In addition to Quellung on cultured isolates when available, serotypes were identified from urine specimens using UAD1 for PCV13 serotypes and UAD2 for 7 PCV20-unique serotypes (8, 10A, 11A, 12F, 15B, 22F, and 33F) and 4 additional serotypes (2, 9N, 17F, and 20).

Results

Among 12 055 subjects with radiographically confirmed CAP, 1482 were positive for S pneumoniae. PCV13- and PCV20-unique serotypes were associated with 37.7% (n = 559) and 27.0% (n = 400) of cases, respectively; 288 subjects were exclusively diagnosed as positive for S pneumoniae by UAD2. Demographic and clinical disease characteristics were similar between subjects with CAP caused by PCV13 and PCV20-unique serotypes.

Conclusions

The current analysis using UAD2 identified a sizeable proportion of hospitalized adult CAP associated with PCV20-unique serotypes. PCV20 may therefore address the burden of CAP caused by the additional serotypes present in the vaccine.

Importance of non-invasive liver fibrosis scores for mortality and complications development in individuals with type 2 diabetes

AIMS

To evaluate the non-alcoholic fatty liver disease (NAFLD) fibrosis score (NFS) and Fibrosis-4 score (FIB4) as predictors of complications development and mortality in a cohort of type 2 diabetes.

METHODS

554 type 2 diabetic subjects had NFS and FIB4 calculated at baseline. Multivariate Cox and Poisson analyses evaluated the associations between fibrosis scores and the occurrence of microvascular and cardiovascular complications, and all-cause mortality.

RESULTS

According to recommended cut-offs of NFS, 12.8% had advanced fibrosis and 45.9% had absence of advanced fibrosis and of FIB4, 3.8% and 86.1%, respectively. During a median follow-up of 11 years, 217subjects died, 172 had cardiovascular events (CVEs), 184 had renal events, and 139 had retinopathy and 185 neuropathy events. As continuous variables, both scores predicted all-cause mortality: NFS, HR: 1.30 (p = 0.032) and FIB4, HR: 1.24 (p = 0.021); an increased NFS implied in a significant 90% excess risk of mortality, whereas a higher FIB4 in a borderline 69% higher risk. The scores were mainly predictors of mortality in women and for non-cardiovascular deaths. The NFS was a predictor of renal events, mainly for renal function deterioration.

CONCLUSIONS

The NFS and FIB4 predicted all-cause mortality, particularly in women and for non-cardiovascular causes. The NFS predicted adverse renal outcomes. These liver fibrosis scores may improve stratification risk in individuals with diabetes and NAFLD.

Pneumococcal serotype-specific cut-offs based on antibody responses to pneumococcal polysaccharide vaccination in healthy adults

Antibody responses to pneumococcal polysaccharide vaccination are frequently used as a diagnostic tool for humoral immunodeficiencies, part of the larger collection of inborn errors of immunity. Currently, arbitrary criteria, such as a serotype specific titer of >/= 1.3 µg/mL is most often used as a cut-off for interpretation of pneumococcal antibody responses. The magnitude of the antibody response to each of the 23 serotypes in Pneumovax®, and serotype-specific cut-offs in healthy pneumococcal vaccine-naïve adults has not been previously characterized. IgG antibody concentrations were measured prospectively for 23 pneumococcal serotypes pre and 4-6 weeks post-Pneumovax® vaccination in 100 healthy adults, using a multiplex bead-based assay. Antibodies to 19 of 23 serotypes were informative for distinguishing subjects who responded to vaccination, and the serotype threshold was determined to be 9 of 19 serotypes, which characterized an antibody response to pneumococcal vaccination. While this study may facilitate classification of IgG serotype-specific antibody responses post-pneumococcal vaccination in adult patients undergoing diagnostic immunological evaluation for antibody immunodeficiencies or other relevant contexts, additional studies in healthy children and S. pneumoniae protein-conjugate-vaccinated healthy adults will need to be undertaken in the future.

Vaccines for older adults

The proportion of the global population aged 65 and older is rapidly increasing. Infections in this age group, most recently with SARS-CoV-2, cause substantial morbidity and mortality. Major improvements have been made in vaccines for older people, either through the addition of novel adjuvants-as in the new recombinant zoster vaccine and an adjuvanted influenza vaccine-or by increasing antigen concentration, as in influenza vaccines. In this article we review improvements in immunization for the three most important vaccine preventable diseases of aging. The recombinant zoster vaccine has an efficacy of 90% that is minimally affected by the age of the person being vaccinated and persists for more than four years. Increasing antigen dose or inclusion of adjuvant has improved the immunogenicity of influenza vaccines in older adults, although the relative effectiveness of the enhanced influenza vaccines and the durability of the immune response are the focus of ongoing clinical trials. Conjugate and polysaccharide pneumococcal vaccines have similar efficacy against invasive pneumococcal disease and pneumococcal pneumonia caused by vaccine serotypes in older adults. Their relative value varies by setting, depending on the prevalence of vaccine serotypes, largely related to conjugate vaccine coverage in children. Improved efficacy will increase public confidence and uptake of these vaccines. Co-administration of these vaccines is feasible and important for maximal uptake in older people. Development of new vaccine platforms has accelerated following the arrival of SARS-CoV-2, and will likely result in new vaccines against other pathogens in the future.

Estimating pneumococcal vaccine coverage among Australian Indigenous children and children with medically at-risk conditions using record linkage

BACKGROUND

Risk-based recommendations are common for pneumococcal vaccines but little is known about their uptake. In Australia, pneumococcal conjugate vaccine (PCV) was funded only for Aboriginal or Torres Strait Islander (Indigenous) children and those with underlying medical conditions in 2001, and then there were different booster dose recommendations depending on risk after the introduction of universal PCV vaccination in 2005.

METHODS

We measured coverage of PCV dose 3 and additional PCV and 23-valent pneumococcal polysaccharide vaccine (PPV23) doses by risk group among children born in July 2001-December 2012 in two Australian states using linked immunisation and hospitalisation data (available until December 2013). We ascertained medical risk conditions using hospitalisation diagnosis codes and Indigenous status using an established algorithm, comparing coverage for children born pre (2001-2004) and post (2005-2012) universal PCV funding.

RESULTS

Among 1.3 million children, 63,897 (4.9%) were Indigenous and 32,934 (2.5%) had at least one medically at-risk condition identified by age 6 months. For births in 2001-2004, coverage for PCV dose 3 by 1 year of age was 37% for Indigenous, 15% for medically at-risk and 11% in other children, increasing to 83%, 91% and 92%, respectively for births in 2005-2012. In children with medically at-risk conditions, PCV dose 4 coverage by 2 years was 1% for 2001-2004 births, increasing to 9% for 2005-2012 births, with PPV23 coverage by 6 years 3% in both cohorts. Among eligible Indigenous children, PPV23 coverage by 3 years was 45% for 2001-2004 births and 51% for 2005-2012 births.

CONCLUSIONS

Coverage with additional recommended booster doses was very low among children with medical conditions, and only modest among Indigenous children. If additional PCV doses are recommended for some risk groups, especially in the context of routine schedules with reduced doses (e.g. 2 + 1 and 1 + 1), measures to improve implementation will be required.

Immunization coverage among asplenic patients and strategies to increase vaccination compliance: a systematic review and meta-analysis

BACKGROUND

Asplenic or splenectomized patients have a higher risk (ranging from 10 to 50-fold) than the general population of developing an overwhelming post-splenectomy infection (OPSI). Thus, they should receive specific vaccinations to prevent bacterial infections and influenza. The aim of this meta-analysis was to estimate vaccination coverage (VC) with the recommended vaccines among splenectomized patients; strategies recommended in those studies to improve VC worldwide are considered as well.

RESEARCH DESIGN AND METHODS

Scopus, MEDLINE/PubMed, Google Scholar and ISI Web of Knowledge databases were searched. Research papers, short reports, reviews, and meta-analyses published between January 1, 2010 and July 18, 2020 were included; no geographic restrictions were included. Twenty-four studies were included in the meta-analysis.

RESULTS

For anti-pneumococcal vaccination, coverage was 55.1% (95%CI = 41.0-69.2%), for anti-Hib 48.3% (95%CI = 34.3-52.3%), for anti-meningococcal C/ACYW135 33.7% (95%CI = 23.6-43.9%), for anti-meningococcal B 13.3% (95%CI = 7.0-19.5%) and for anti-influenza 53.2% (95%CI = 22.0-84.4%). Most studies determined a lack of adherence to international guidelines by healthcare workers and suggested the need to better educate health professionals in the management of post-splenectomy patients.

CONCLUSIONS

The meta-analysis showed the suboptimal immunization coverage for the vaccines recommended for asplenic patients. Greater efforts must be made by public health professionals to increase VC in this group of patients at risk. Introducing specific prophylaxis protocols in the clinical routine seems to guarantee better immunization compliance in those patients.