Effectiveness of 23-valent pneumococcal polysaccharide vaccine against invasive disease and hospital-treated pneumonia among people aged ≥65 years: a retrospective case-control study

Follow-Up Study of Effectiveness of 23-Valent Pneumococcal Polysaccharide Vaccine Against All-Type and Serotype-Specific Invasive Pneumococcal Disease, Denmark

As a follow-up to a previous study, we investigated vaccine effectiveness (VE) of 23-valent pneumococcal polysaccharide vaccine (PPSV23) against invasive pneumococcal disease (IPD) among 1,254,498 persons >65 years of age as part of a vaccination program in Denmark during April 2020-January 2023. We assessed VE by using a Cox regression model and adjusted for age, sex, and underlying conditions. Using nationwide data, we estimated a VE of PPSV23 against all-type IPD of 32% and against PPSV23-serotype IPD of 41%. Because this follow-up study had more statistical power than the original study, we also estimated VE against IPD caused by PPSV23-serotypes excluding serotype 3; serotype 3; serotype 8; serotype 22F; PPSV23 non-PCV15 serotypes; PPSV23 non-PCV20 serotypes; and IPD over time. Our findings suggest PPSV23 vaccination can protect persons >65 years of age against IPD caused by all serotypes or serotype groupings, except serotype 3.

The role of vaccination in COPD: influenza, SARS-CoV-2, pneumococcus, pertussis, RSV and varicella zoster virus

Exacerbations of COPD are associated with worsening of the airflow obstruction, hospitalisation, reduced quality of life, disease progression and death. At least 70% of COPD exacerbations are infectious in origin, with respiratory viruses identified in approximately 30% of cases. Despite long-standing recommendations to vaccinate patients with COPD, vaccination rates remain suboptimal in this population.Streptococcus pneumoniae is one of the leading morbidity and mortality causes of lower respiratory tract infections. The Food and Drug Administration recently approved pneumococcal conjugate vaccines that showed strong immunogenicity against all 20 included serotypes. Influenza is the second most common virus linked to severe acute exacerbations of COPD. The variable vaccine efficacy across virus subtypes and the impaired immune response are significant drawbacks in the influenza vaccination strategy. High-dose and adjuvant vaccines are new approaches to tackle these problems. Respiratory syncytial virus is another virus known to cause acute exacerbations of COPD. The vaccine candidate RSVPreF3 is the first authorised for the prevention of RSV in adults ≥60 years and might help to reduce acute exacerbations of COPD. The 2023 Global Initiative for Chronic Lung Disease report recommends zoster vaccination to protect against shingles for people with COPD over 50 years.

Methods for the Inclusion of Real-World Evidence in a Rare Events Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Many rare events meta-analyses of randomized controlled trials (RCTs) have lower statistical power, and real-world evidence (RWE) is becoming widely recognized as a valuable source of evidence. The purpose of this study is to investigate methods for including RWE in a rare events meta-analysis of RCTs and the impact on the level of uncertainty around the estimates.

METHODS

Four methods for the inclusion of RWE in evidence synthesis were investigated by applying them to two previously published rare events meta-analyses: the naïve data synthesis (NDS), the design-adjusted synthesis (DAS), the use of RWE as prior information (RPI), and the three-level hierarchical models (THMs). We gauged the effect of the inclusion of RWE by varying the degree of confidence placed in RWE.

RESULTS

This study showed that the inclusion of RWE in a rare events meta-analysis of RCTs could increase the precision of the estimates, but this depended on the method of inclusion and the level of confidence placed in RWE. NDS cannot consider the bias of RWE, and its results may be misleading. DAS resulted in stable estimates for the two examples, regardless of whether we placed high- or low-level confidence in RWE. The results of the RPI approach were sensitive to the confidence level placed in RWE. The THM was effective in allowing for accommodating differences between study types, while it had a conservative result compared with other methods.

CONCLUSION

The inclusion of RWE in a rare events meta-analysis of RCTs could increase the level of certainty of the estimates and enhance the decision-making process. DAS might be appropriate for inclusion of RWE in a rare event meta-analysis of RCTs, but further evaluation in different scenarios of empirical or simulation studies is still warranted.

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.

Vaccine effectiveness of the pneumococcal polysaccharide and conjugated vaccines in elderly and high-risk populations in preventing invasive pneumococcal disease: a systematic search and meta-analysis

BACKGROUND

Invasive pneumococcal disease (IPD) is a major cause of morbidity and mortality globally. However, the literature on the vaccine effectiveness (VE) of 23-valent polysaccharide vaccine (PPV23) and 13-valent conjugated vaccine (PCV13) against IPD in adults is sparse. The aim was to summarize the available evidence on the VE of the PPV23 and the PCV13 in elderly individuals against IPD and to investigate how age and comorbidities influence VE against IPD.

METHODS

A systematic search was conducted in Medline and Embase in February 2021. We used combinations of terms related to PPV23, PCV13, elderly, high-risk populations, and IPD. Eligible articles published since 2010 were included. Two authors reviewed and extracted data.

RESULTS

Eight studies met the inclusion criteria for PPV23. The meta-analysis showed a reduced OR for all-type IPD with the use of PPV23 vaccine compared with unvaccinated controls (OR 0.69; 95%CI 0.54, 0.88) and a reduced OR for vaccine-type IPD compared with non-vaccine type IPD (0.69; 95%CI 0.63, 0.76). VE against vaccine-type IPD ranged from 28% to 54.1% for individuals aged 65-79 and from 7.5% to 34% for those aged ≥80-85 years. Most studies found a lower VE of PPV23 in populations with comorbidities and in immunocompromised populations compared with the VE for individuals without comorbidities.One study met the inclusion criteria for PCV13. The vaccine efficacy of PCV13 against IPD in individuals aged ≥65 was 75.0% (95% CI, 41.4 to 90.8).

CONCLUSION

The results from this review show a reduction of IPD in elderly and high-risk populations vaccinated with PPV23 and PCV13. The protective effect may be lower in elderly individuals aged >80 and in individuals with comorbidities. However, the literature is sparse; large-scale prospective studies are required to evaluate the VE of PPV23 and PCV13 vaccination in adults against IPD.

Invasive Pneumococcal Disease and COVID-19 Coinfection: A Series of Cases Admitted to an Intensive Care Unit

Pneumococcal infection is still a frequent disease. It can be classified as invasive when pneumococcus is isolated in a generally sterile fluid. Pneumonia is the most common infectious source of adult invasive pneumococcal disease (IPD), and several risk factors for IPD are well known. This case report presents three clinical cases of different manifestations of IPD. The two most severe cases had coinfection by SARS-CoV-2 at hospital admission.

23-Valent Pneumococcal Polysaccharide Vaccination Does Not Prevent Community-Acquired Pneumonia Hospitalizations Due to Vaccine-Type Streptococcus pneumoniae

Controversy exists regarding the clinical effectiveness of the 23-valent pneumococcal polysaccharide vaccine (PPSV23) for the prevention of serotype-specific community-acquired pneumonia (CAP). The objective of this study was to define the effectiveness of PPSV23 for the prevention of CAP hospitalizations due to vaccine-contained serotypes. This secondary analysis was a nested case–control, test-negative study design of adult patients hospitalized for CAP between 1 June 2014 and 31 March 2017. Cases included patients with CAP due to a S. pneumoniae serotype contained in the PPSV23. Urinary antigen detection of the 23 serotypes was performed. In the study, PPSV23 vaccination alone and no other pneumococcal vaccination was the primary exposure of interest. Vaccine effectiveness was calculated as (1-OR) × 100. Adjusted estimates were obtained from a logistic regression model that controlled for confounding variables. A total of 3686 patients were included in the analysis. The PPSV23 vaccination was documented in 608 (16%) patients, and the PPSV23-serotype CAP was detected in 48 (8%) PPSV23-vaccinated patients and in 288 (9%) non-vaccinated patients. Unadjusted vaccine effectiveness for preventing PPSV23-serotype CAP was 17% (95% CI: −13% to 40%). Adjusted estimates for preventing PPSV23-serotype CAP was 14% (95% CI: −17% to 38%). In this study, PPSV23 vaccination offered no protection against PPSV23-serotype CAP hospitalization in adults. This is the first PPSV23 vaccine effectiveness study from United States that utilized a urinary antigen detection assay as the main method for S. pneumoniae serotyping. This study highlights the need for more effective vaccines in the prevention of hospitalization due to S. pneumoniae CAP.

Cost-effectiveness and budget impact analysis of PPV23 vaccination for the Malaysian Hajj pilgrims

The potential occurrence of disease outbreaks during the hajj season is of great concern due to extreme congestion in a confined space. This promotes the acquisition, spread and transmission of pathogenic microorganisms and pneumococcal disease are one of the most frequent infections among Hajj pilgrims. This study aimed to assess the cost-effectiveness and budget impact of introducing the PPV23 to Malaysian Hajj pilgrims. A decision tree framework with a 1-year cycle length was adapted to evaluate the cost-effectiveness of a PPV23 vaccination program with no vaccination. The cost information was retrieved from the Lembaga Tabung Haji Malaysia (LTH) database. Vaccine effectiveness was based on the locally published data and the disease incidence specifically related to Streptococcus pneumoniae was based on a literature search. Analyses were conducted from the perspective of the provider: Ministry of Health and LTH Malaysia. The incremental cost-effectiveness ratios (ICER), cases averted, and net cost savings were estimated. Findings from this study showed that PPV23 vaccination for Malaysian Hajj pilgrims was cost-effective. The PPV23 vaccination programme has an ICER of MYR -449.3 (US$-110.95) per case averted. Based on the national threshold value of US$6,200-US$8,900 per capita, the base-case result shows that introduction of the PPV23 vaccine for Malaysian Hajj pilgrims is very cost-effective. Sensitivity analysis revealed parameters related to annual incidence and hospitalised cost of septicemia and disease without vaccination as the key drivers of the model outputs. Compared with no vaccination, the inclusion of PPV23 vaccination for Malaysian Hajj pilgrims was projected to result in a net cost saving of MYR59.6 million and 109,996 cases averted over 5 years period. The PPV23 vaccination program could substantially offer additional benefits in reducing the pneumococcal disease burden and healthcare cost. This could be of help for policymakers to consider the implementation of PPV23 vaccination for Malaysian performing hajj.

A randomized phase 1/2 study of the safety and immunogenicity of a multivalent pneumococcal conjugate vaccine in healthy adults 50 through 85 years of age

Pneumococcal disease can be serious and debilitating in older adults. Pneumococcal conjugate vaccines (PCVs), such as the 13-valent PCV (PCV13), reduce pneumococcal disease rates caused by vaccine serotypes. Development of PCVs offering additional coverage against serotypes not contained in PCV13 can reduce disease burden further. The complementary 7-valent PCV (cPCV7) contains seven non-PCV13 serotypes (8, 10A, 11A, 12F, 15B, 22F, 33F) and can expand coverage by supplementing direct or indirect protection from existing PCVs. This phase 1/2, randomized, active-controlled, observer-blinded study evaluated cPCV7 safety and immunogenicity in healthy adults 50–85 years of age. Stage 1 randomized 66 healthy adults (50–64 years) naive to pneumococcal vaccines to receive cPCV7 or licensed tetanus, diphtheria, and acellular pertussis vaccine; Stage 2 randomized 445 healthy adults (65–85 years) previously vaccinated with PCV13 to receive cPCV7 or 23-valent polysaccharide vaccine. Local reactions and systemic events up to 14 days and adverse events (AEs) through 1 month after vaccination were assessed. Immunogenicity was evaluated by serotype-specific opsonophagocytic activity (OPA) assays before and 1 month after vaccination (and after 12 months in Stage 2). Rates of local reactions, systemic events, and AEs were generally similar after receipt of cPCV7 or control. Robust OPA responses were observed for all seven serotypes 1 month after cPCV7; titers declined yet remained above baseline 12 months after vaccination. Overall, this study found that in adults ≥50 years of age, cPCV7 was safe, well tolerated, and elicited functional immune responses to vaccine serotypes. ClinicalTrials.gov: NCT03313050

Serotype distribution and antimicrobial susceptibility of Streptococcus pneumoniae isolates from a Phase III community-acquired bacterial pneumonia (CABP) trial

Objectives

To report Streptococcus pneumoniae serotyping and susceptibility data from a recent clinical trial (ML-3341-306) comparing delafloxacin with moxifloxacin in the treatment of adults with community-acquired bacterial pneumonia (CABP).

Methods

Serotyping and susceptibility testing were conducted on 142 baseline S. pneumoniae isolates recovered from subjects participating in a CABP clinical trial.

Results

Overall, 113/142 (79.6%) isolates were vaccine serotypes. 76.8% (109/142) of serotyped isolates were PPSV23 serotypes and 59.9% (85/142) of isolates were PCV13 serotypes. 15.5% (22/142) of serotyped isolates were serotypes not covered by either vaccine; 4.9% (7/142) of tested isolates were non-typeable. The most common serotypes were serotypes 3 (19.0%; 27/142), 19F (9.9%; 14/142) and 23F (7.0%; 10/142). All of the 142 isolates were susceptible to delafloxacin and moxifloxacin, 76.1% were susceptible to azithromycin and 71.8% were susceptible to penicillin. Multidrug resistance was found among 19A (4/5; 80%), 6A (1/4; 25%), 6B (1/4; 25%), 14 (1/4; 25%), 19F (1/14; 7.1%), and 23F serotypes (2/10; 20%), and among non-typeable S. pneumoniae isolates (1/7; 14.3%).

Conclusions

S. pneumoniae vaccine-targeted serotypes were the main cause of CABP in this Phase 3 CABP study. Fluoroquinolones including delafloxacin remain a good treatment option for CABP in adults caused by S. pneumoniae.

Protective potency of recombinant meningococcal IgA1 protease and its structural derivatives upon animal invasion with meningococcal and pneumococcal infections

Immunization of mice with recombinant IgA1 protease of Neisseria meningitidis or several structural derivatives thereof protects the animals infected with a variety of deadly pathogens, including N. meningitidis serogroups A, B, and C and 3 serotypes of Streptococcus pneumonia. In sera of rabbits immunized with inactivated pneumococcal cultures, antibodies binding IgA1-protease from N. meningitidis serogroup B were detected. Thus, the cross-reactive protection against meningococcal and pneumococcal infections has been demonstrated in vivo. Presumably it indicates the presence of common epitopes in the N. meningitidis IgA1 protease and S. pneumoniae surface proteins.

Triptych of the Hermit Saints: pneumococcal polysaccharide vaccines for the elderly

Pneumococcal pneumonia is a serious disease with considerable morbidity and mortality in the elderly. Despite adequate antibiotic treatment, the long-term mortality of pneumococcal pneumonia remains high. Preventive measures in the form of vaccination, therefore, are warranted. Twenty-three-valent polysaccharide vaccines have a broad coverage but limited efficacy. Pneumococcal conjugate vaccines have been shown in children to be able to prevent invasive and mucosal pneumococcal diseases. It should be realized that the serotype composition of current pneumococcal conjugate vaccines is not tailored for the elderly, and that replacement disease can occur. Yet, the current 13-valent conjugate vaccine has been shown to protect against infections with vaccine serotypes. Long-term mortality of pneumococcal pneumonia should be included in policy making about the introduction of these vaccines for the elderly.

Burden of pneumococcal community-acquired pneumonia in adults across Europe: A literature review

BACKGROUND

The burden of community-acquired pneumonia (CAP) caused by Streptococcus pneumoniae (pneumococcus) among adults in Europe is poorly defined.

METHODS

Structured searches of PubMed were conducted to identify the incidence of pneumococcal CAP among adults across Europe.

RESULTS

The overall incidence rates for CAP was 68-7000 per 100,000 and the incidence in hospitalised CAP cases of all causes was 16-3581 per 100,000. In general the incidence of CAP increased consistently with age. Available data indicated higher burdens of pneumococcal CAP caused in groups with more comorbidities. Most cases of pneumococcal CAP (30%-78%) were caused by serotypes covered by PCV13 vaccine; the incidence of PCV13-related pneumonia decreased after the introduction of childhood vaccination.

CONCLUSIONS

We observed a high burden adult pneumococcal CAP in Europe despite use of the 23-valent pneumococcal polysaccharide vaccine, particularly in elderly patients with comorbidities. CAP surveillance presented wide variations across Europe. Pneumococcal CAP has to be monitored very carefully due to the possible effect of current vaccination strategies.

Pneumococcal vaccination in older persons: where are we today?

Disease due to Streptococcus pneumoniae, the pneumococcus, remains a major source of illness in older persons. Globally, it remains the most important pathogen in respiratory infection deaths.

Conjugated pneumococcal vaccines are used extensively in national pediatric programs, whereas a polysaccharide vaccine is used in all age groups, but mainly in the elderly and for high-risk groups.

Recent data from the Netherlands led to the licensing in many countries of conjugated pneumococcal vaccines for older persons. There are substantial differences in recommendations from various national immunization technical advisory groups, which owe at least as much to differing assessments of available studies as to differences in local epidemiology.

This review examines those differences and proposes a way forward.

The full benefits of adult pneumococcal vaccination: A systematic review

Background

Pneumococcal disease causes substantial morbidity and mortality, including among adults. Adult pneumococcal vaccines help to prevent these burdens, but they are underused. Accounting for the full benefits of adult pneumococcal vaccination may promote more rational resource allocation decisions with respect to adult pneumococcal vaccines.

Objectives

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we conducted a systematic review to assess the extent to which the literature has empirically captured (e.g., through measurement or modeling) the full benefits of adult pneumococcal vaccination.

Methods

We systematically searched PubMed and Embase to identify studies published between January 1, 2010 and April 10, 2016 that examine adult pneumococcal vaccination. We included articles if they captured any health or economic benefit of an adult pneumococcal vaccine administered to adults age ≥ 50 or ≥ 18 in risk groups. Finally, we summarized the literature by categorizing the types of benefits captured, the perspective taken, and the strength of the evidence presented. Our protocol is number 42016038335 in the PROSPERO International prospective register of systematic reviews.

Results

We identified 5,857 papers and included 150 studies for analysis. While most capture health gains and healthcare cost savings, far fewer studies consider additional benefit categories, such as productivity gains. However, the studies with a broader approach still exhibit significant limitations; for example, many present only abstracts, while others offer no new measurements. Studies that examine the 13-valent pneumococcal conjugate vaccine focus more on broad economic benefits, but still have limitations.

Conclusions

This review highlights the need for more robust empirical accounting of the full benefits of adult pneumococcal vaccination. Literature outside this realm indicates that these broad benefits may be substantial. Failing to investigate the full benefits may lead society to undervalue vaccines' contributions and therefore underinvest in their development and adoption.

Oligosaccharide ligand tuning in design of third generation carbohydrate pneumococcal vaccines

Streptococcus pneumoniae can cause many types of dangerous infectious diseases such as otitis media, pneumonia, meningitis and others that are more common in the very young and very old age. Available to date commercial vaccines based on capsular polysaccharides of S. pneumoniae of clinically important strains (first generation carbohydrate vaccines) and conjugated vaccines based on these polysaccharides (second generation carbohydrate vaccines) have certain limitations in protective efficiency. However, the efficiency of vaccines can be increased by the use of third generation vaccines based on synthetic oligosaccharide ligands representing in their structures the protective epitopes of capsular polysaccharides. The proper choice of an optimal oligosaccharide ligand is the most important step in the design of third generation carbohydrate vaccines. Herein we overview our works on the synthesis of three oligosaccharides corresponding to one, “one and a half” and two repeating units of S. pneumoniae type 14 capsular polysaccharide, immunogenic conjugates thereof and comparative immunological study of their conjugates with bovine serum albumin, which was used as a model protein carrier. The ability of obtained products to raise antibodies specific to capsular polysaccharide and homologous oligosaccharides, the induction of phagocytosis by immune antisera and active protection of immunized animals from S. pneumoniae type 14 infection were evaluated. On the basis of the results obtained tetrasaccharide comprising the repeating unit of S. pneumoniae type 14 capsular polysaccharide is an optimal carbohydrate ligand to be used as a part of the third generation carbohydrate pneumococcal vaccine.

Epidemiological characteristics associated with uptake of pneumococcal vaccine among older adults living in the community in Singapore: Results from the National Health Surveillance Survey 2013

AIMS

In Singapore, pneumococcal vaccination is recommended for the elderly (i.e. those ≥65 years of age) and people with chronic medical conditions. We investigated epidemiological characteristics associated with the uptake of pneumococcal vaccine based on a nationally representative cross-sectional sample of community-living adults aged ≥50 years.

METHODS

The data were obtained from the National Health Surveillance Survey (NHSS) 2013. Associations between pneumococcal vaccination and sociodemographic and health-related variables were analysed using univariable and multivariable logistic regression models.

RESULTS

Among 3672 respondents aged ≥50 years in the NHSS, 7.8% had taken the pneumococcal vaccination. A higher level of education and higher monthly household income were sociodemographic characteristics independently associated with pneumococcal vaccine uptake. Health-related characteristics predictive of pneumococcal vaccine uptake were better self-rated health and having a regular family doctor/general practitioner. Among those who responded to the two questions on vaccinations, 3.9% had been vaccinated against both seasonal influenza and pneumococcal infection, while 11.1% had taken only seasonal influenza vaccination in the past year.

CONCLUSIONS

There is a need to boost pneumococcal vaccination coverage among community-dwelling older adults. These findings provide insights into reviewing and tailoring public-health strategies and programmes to increase vaccine uptake in at-risk population groups.

Pneumococcal conjugate vaccine use in adults - Addressing an unmet medical need for non-bacteremic pneumococcal pneumonia

Streptococcus pneumoniae is a frequent cause of community acquired pneumonia (CAP), with the largest burden of disease attributed to non-bacteremic pneumonia. Due to the high persistent burden of disease, pneumococcal pneumonia, particularly non-bacteremic pneumococcal pneumonia, continues to be a major public health concern. There are currently two pneumococcal vaccines approved for use in adults in the United States (US) and other countries worldwide: a 23-valent pneumococcal simple polysaccharide vaccine (PPV23), and a 13-valent pneumococcal conjugate vaccine (PCV13). The capsular polysaccharides included in PPV23 induce antibodies primarily by a T-cell independent mechanism, thus the immune response is short lived and lacks the ability to elicit an anamnestic response. PCV13, on the other hand, has the bacterial polysaccharides covalently conjugated to an immunogenic carrier protein resulting in the formation of memory B lymphocytes, thus proving long-acting immunologic memory and an anamnestic response. Despite 30years of use, the question of PPV23 vaccine efficacy, particularly with respect to efficacy for non-bacteremic pneumonia, has been extensively debated and investigated; whereas PCV13 efficacy against vaccine-type pneumococcal CAP, both bacteremic and non-bacteremic, was confirmed in a large randomized controlled trial in older adults. PCV13 was approved under the US Food and Drug Administration's accelerated pathway, which allows for earlier approval of products that provide meaningful benefit over existing treatments - in this case, protection of adults from non-bacteremic pneumococcal pneumonia. Its use is now increasingly recommended globally. This article summarizes the history and use of PPV23 and PCV13 in adults and how vaccination of adults with PCV13 addresses an unmet medical need.

Neoglycoconjugate of Tetrasaccharide Representing One Repeating Unit of the Streptococcus pneumoniae Type 14 Capsular Polysaccharide Induces the Production of Opsonizing IgG1 Antibodies and Possesses the Highest Protective Activity As Compared to Hexa- and Octasaccharide Conjugates

Identifying protective synthetic oligosaccharide (OS) epitopes of Streptococcus pneumoniae capsular polysaccharides (CPs) is an indispensable step in the development of third-generation carbohydrate pneumococcal vaccines. Synthetic tetra-, hexa-, and octasaccharide structurally related to CP of S. pneumoniae type 14 were coupled to bovine serum albumin (BSA), adjuvanted with aluminum hydroxide, and tested for their immunogenicity in mice upon intraperitoneal prime-boost immunizations. Injections of the conjugates induced production of opsonizing anti-OS IgG1 antibodies (Abs). Immunization with the tetra- and octasaccharide conjugates stimulated the highest titers of the specific Abs. Further, the tetrasaccharide ligand demonstrated the highest ability to bind OS and CP Abs. Murine immune sera developed against tetra- and octasaccharide conjugates promoted pathogen opsonization to a higher degree than antisera against conjugated hexasaccharide. For the first time, the protective activities of these glycoconjugates were demonstrated in mouse model of generalized pneumococcal infections. The tetrasaccharide conjugate possessed the highest protective activities. Conversely, the octasaccharide conjugate had lower protective activities and the lowest one showed the hexasaccharide conjugate. Sera against all of the glycoconjugates passively protected naive mice from pneumococcal infections. Given that the BSA-tetrasaccharide induced the most abundant yield of specific Abs and the best protective activity, this OS may be regarded as the most promising candidate for the development of conjugated vaccines against S. pneumoniae type 14 infections.

Effectiveness of pneumococcal vaccines in preventing pneumonia in adults, a systematic review and meta-analyses of observational studies

INTRODUCTION

S. pneumoniae can cause a wide spectrum of diseases, including invasive pneumococcal disease and pneumonia. Two types of pneumococcal vaccines are indicated for use in adults: 23-valent pneumococcal polysaccharide vaccines (PPV23) and a 13-valent pneumococcal conjugate vaccine (PCV13).

OBJECTIVE

To systematically review the literature assessing pneumococcal vaccine effectiveness (VE) against community-acquired pneumonia (CAP) in adults among the general population, the immunocompromised and subjects with underlying risk factors in real-world settings.

METHODS

We searched for peer-reviewed observational studies published between 1980 and 2015 in Pubmed, SciELO or LILACS, with pneumococcal VE estimates against CAP, pneumococcal CAP or nonbacteremic pneumococcal CAP. Meta-analyses and meta-regression for VE against CAP requiring hospitalization in the general population was performed.

RESULTS

1159 unique articles were retrieved of which 33 were included. No studies evaluating PCV13 effectiveness were found. Wide ranges in PPV23 effectiveness estimates for any-CAP were observed among adults ≥65 years (-143% to 60%). The meta-analyzed VE estimate for any-CAP requiring hospitalization in the general population was 10.2% (95%CI: -12.6; 33.0). The meta-regression indicates that VE against any-CAP requiring hospitalization is significantly lower in studies with a maximum time since vaccination ≥60 months vs. <60 months and in countries with the pediatric PCV vaccine available on the private market. However, these results should be interpreted cautiously due to the high influence of two studies. The VE estimates for pneumococcal CAP hospitalization ranged from 32% (95%CI: -18; 61) to 51% (95%CI: 16; 71) in the general population.

CONCLUSIONS

Wide ranges in PPV23 effectiveness estimates for any-CAP were observed, likely due to a great diversity of study populations, circulation of S. pneumoniae serotypes, coverage of pediatric pneumococcal vaccination, case definition and time since vaccination. Despite some evidence for short-term protection, effectiveness of PPV23 against CAP was not consistent in the general population, the immunocompromised and subjects with underlying risk factors.

Effectiveness of 23-valent pneumococcal polysaccharide vaccination in preventing community-acquired pneumonia hospitalization and severe outcomes in the elderly in Spain

Pneumococcal pneumonia is a serious cause of morbidity and mortality in the elderly, but investigation of the etiological agent of community-acquired pneumonia (CAP) is not possible in most hospitalized patients. The aim of this study was to estimate the effect of pneumococcal polysaccharide vaccination (PPSV23) in preventing CAP hospitalization and reducing the risk of intensive care unit admission (ICU) and fatal outcomes in hospitalized people aged ≥65 years. We made a multicenter case-control study in 20 Spanish hospitals during 2013-2014 and 2014-2015. We selected patients aged ≥65 years hospitalized with a diagnosis of pneumonia and controls matched by sex, age and date of hospitalization. Multivariate analysis was performed using conditional logistic regression to estimate vaccine effectiveness and unconditional logistic regression to evaluate the reduction in the risk of severe and fatal outcomes. 1895 cases and 1895 controls were included; 13.7% of cases and 14.4% of controls had received PPSV23 in the last five years. The effectiveness of PPSV23 in preventing CAP hospitalization was 15.2% (95% CI -3.1-30.3). The benefit of PPSV23 in avoiding ICU admission or death was 28.1% (95% CI -14.3-56.9) in all patients, 30.9% (95% CI -32.2-67.4) in immunocompetent patients and 26.9% (95% CI -38.6-64.8) in immunocompromised patients. In conclusion, PPSV23 showed a modest trend to avoidance of hospitalizations due to CAP and to the prevention of death or ICU admission in elderly patients hospitalized with a diagnosis of CAP.

Effectiveness of the 23-Valent Pneumococcal Polysaccharide Vaccine (PPV23) against Pneumococcal Disease in the Elderly: Systematic Review and Meta-Analysis

BACKGROUND

Routine vaccination of elderly people against pneumococcal diseases is recommended in many countries. National guidelines differ, recommending either the 23-valent polysaccharide vaccine (PPV23), the 13-valent conjugate vaccine (PCV13) or both. Considering the ongoing debate on the effectiveness of PPV23, we performed a systematic literature review and meta-analysis of the vaccine efficacy/effectiveness (VE) of PPV23 against invasive pneumococcal disease (IPD) and pneumococcal pneumonia in adults aged ≥60 years living in industrialized countries.

METHODS

We searched for pertinent clinical trials and observational studies in databases MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews. We assessed the risk of bias of individual studies using the Cochrane Risk of Bias tool for randomized controlled trials and the Newcastle-Ottawa Scale for observational studies. We rated the overall quality of the evidence by GRADE criteria. We performed meta-analyses of studies grouped by outcome and study design using random-effects models. We applied a sensitivity analysis excluding studies with high risk of bias.

RESULTS

We identified 17 eligible studies. Pooled VE against IPD (by any serotype) was 73% (95%CI: 10-92%) in four clinical trials, 45% (95%CI: 15-65%) in three cohort studies, and 59% (95%CI: 35-74%) in three case-control studies. After excluding studies with high risk of bias, pooled VE against pneumococcal pneumonia (by any serotype) was 64% (95%CI: 35-80%) in two clinical trials and 48% (95%CI: 25-63%) in two cohort studies. Higher VE estimates in trials (follow-up ~2.5 years) than in observational studies (follow-up ~5 years) may indicate waning protection. Unlike previous meta-analyses, we excluded two trials with high risk of bias regarding the outcome pneumococcal pneumonia, because diagnosis was based on serologic methods with insufficient specificity.

CONCLUSIONS

Our meta-analysis revealed significant VE of PPV23 against both IPD and pneumococcal pneumonia by any serotype in the elderly, comparable to the efficacy of PCV13 against vaccine-serotype disease in a recent clinical trial in elderly people. Due to its broader serotype coverage and the decrease of PCV13 serotypes among adults resulting from routine infant immunization with PCV13, PPV23 continues to play an important role for protecting adults against IPD and pneumococcal pneumonia.

Pneumococcal vaccination

PURPOSE OF REVIEW

Pneumococcal diseases (invasive diseases, pneumonia, otitis media, and sinusitis) are among the most frequent preventable infectious diseases carrying a very high morbidity and case fatality rate worldwide. Pneumococcal vaccination is a key element to reduce the global burden of the disease in children and adult population. Our aim is to discuss current knowledge of the epidemiology of pneumococcal disease and pneumococcal vaccines.

RECENT FINDINGS

After the introduction of conjugate vaccines (PCV7 and PCV13), rates of pneumococcal diseases because of vaccine serotypes have decreased considerably among children in the vaccine target and among nonvaccinated children and adults. Results of the Community-Acquired Pneumonia Immunization Trial in Adults demonstrated 45.6% efficacy of PCV13 against the first episode of pneumonia, 45% against first-episode nonbacteremic pneumococcal pneumonia, and 75% against the first episode of invasive pneumococcal diseases in adults older than 65 years. Recommendations for pneumococcal vaccination have changed recently in both the United States and Europe.

SUMMARY

The changing epidemiology of pneumococcal diseases should be closely investigated to assess the effectiveness and the usefulness of the current vaccination policies, and to identify future directions for preventing pneumococcal infections.

Burden of pneumococcal disease in adults aged 65 years and older: an Australian perspective

BACKGROUND

The burden of pneumococcal disease in adults aged 65 years and older in Australia is not well defined. This retrospective cross-sectional study calculated rates for pneumococcal pneumonia using data from the Australian Institute of Health and Welfare and from the Bettering Evaluation and Care of Health program.

METHODS

Invasive pneumococcal disease (IPD) incidence was calculated using National Notifiable Diseases Surveillance System data. Population estimates and pneumonia mortality data were from the Australian Bureau of Statistics. Medical costs were derived from Australian Refined Diagnosis Related Groups and the literature. Clinical and economic burden of pneumococcal pneumonia hospitalisations and general practitioner (GP) visits were described and compared with IPD.

RESULTS

For adults aged ≥65 years, pneumococcal pneumonia hospitalisation incidence was 274 per 100,000 population in 2011-2012. From 2004 to 2012, a mean of 2235 pneumonia hospitalisation deaths were recorded, corresponding to a case fatality rate of 6.1 %. GP visits accounted for the largest portion of healthcare encounters, with an annual average of 455 pneumococcal pneumonia GP visits per 100,000 population from 2008 to 2013. In 2012, IPD incidence was 19 per 100,000 population. The estimated annual costs of treating pneumococcal pneumonia hospitalisations and GP visits were A$55,722,136 and A$1,604,189, respectively. Estimated costs for IPD were A$1,172,986.

CONCLUSIONS

The healthcare and economic burden of pneumococcal disease in adults aged ≥65 years in Australia is substantial, with the incidence of pneumococcal pneumonia hospitalisation nearly 15-fold higher than for IPD. Despite this, it remains less recognised than other infectious diseases such as influenza.

Effectiveness of 23-valent pneumococcal polysaccharide vaccine on diabetic elderly

Diabetes mellitus is associated with increased risk of pneumonia, and 23-valent pneumococcal polysaccharide vaccine (PPV23) is recommended for prevention of pneumonia. However, the effectiveness of PPV23 remains unclear in the older diabetic patients who usually have compromised immune function.We used data extracted from the Taiwanese National Health Insurance Research Database (NHIRD) from 2000 to 2009 to conduct a population-based retrospective cohort study, comparing the incidence of pneumococcal diseases among PPV23-vaccinated and propensity-score matched PPV23-unvaccinated groups in diabetic elderly. The primary outcome was invasive pneumococcal diseases (IPDs), and the secondary outcomes were medical utilization.PPV23-vaccinated group had reduced risks of IPD (adjusted OR: 0.86, 95% CI: 0.78-0.94), respiratory failure (0.84, 0.77-0.93), and shorter length of hospitalization (-1.27 ± 0.19 days, P value: 0.0012). In flu-vaccinated group, subjects who received PPV23 had reduced risks of IPD, hospitalization, and respiratory failure; had shorter lengths of hospitalization; and less medical costs, than those without receiving PPV23. In not flu-vaccinated group, PPV23 vaccination was associated with reduced risks of IPD and respiratory failure. Receiving both vaccines could bring better protection in IPD, hospitalization, visits of emergency department, and respiratory failure.PPV23 vaccination was effective in prevention of pneumococcal diseases and reduction of medical utilization in diabetic elderly aged 75 and more. Receiving both vaccines resulted in better outcomes than PPV vaccination alone.

Surveillance of pneumococcal diseases in Central and Eastern Europe

Pneumococcal infection is a major cause of morbidity and mortality worldwide. The burden of disease associated with S. pneumoniae is largely preventable through routine vaccination. Pneumococcal conjugate vaccines (e.g. PCV7, PCV13) provide protection from invasive pneumococcal disease as well as non-invasive infection (pneumonia, acute otitis media), and decrease vaccine-type nasopharyngeal colonisation, thus reducing transmission to unvaccinated individuals. PCVs have also been shown to reduce the incidence of antibiotic-resistant pneumococcal disease. Surveillance for pneumococcal disease is important to understand local epidemiology, serotype distribution and antibiotic resistance rates. Surveillance systems also help to inform policy development, including vaccine recommendations, and monitor the impact of pneumococcal vaccination. National pneumococcal surveillance systems exist in a number of countries in Central and Eastern Europe (such as Croatia, Czech Republic, Hungary, Poland, Romania and Slovakia), and some have introduced PCVs (Czech Republic, Hungary, Kazakhstan, Russia, Slovakia and Turkey). Those countries without established programs (such as Kazakhstan, Russia and Ukraine) may be able to learn from the experiences of those with national surveillance systems. The serotype distributions and impact of PCV13 on pediatric pneumococcal diseases are relatively similar in different parts of the world, suggesting that approaches to vaccination used elsewhere are also likely to be effective in Central and Eastern Europe. This article briefly reviews the epidemiology of pneumococcal disease, presents the latest surveillance data from Central and Eastern Europe, and discusses any similarities and differences in these data as well the potential implications for vaccination policies in the region.

Invasive Bacterial Diseases in Northern Canada, 2006-2013

BACKGROUND

Northern populations were at a high risk of developing invasive bacterial diseases (IBDs). Since the last published study that described IBDs in Northern Canada, a number of vaccines against some bacterial pathogens have been introduced into the routine childhood immunization schedule.

OBJECTIVE

To describe the epidemiology of IBDs in Northern Canada from 2006 to 2013.

METHODS

Data for 5 IBDs (invasive pneumococcal disease (IPD), invasive Haemophilus influenzae disease (Hi), invasive Group A streptococcal disease (iGAS), invasive meningococcal disease (IMD) and invasive Group B streptococcal disease (GBS)) were extracted from the International Circumpolar Surveillance (ICS) program and the Canadian Notifiable Diseases Surveillance System. Incidence rates were calculated per 100,000 population per year.

RESULTS

During the study period, the incidence rates of IPD ranged from 16.84-30.97, iGAS 2.70-17.06, Hi serotype b 0-2.78, Hi non-b type 2.73-8.53, and IMD 0-3.47. Except for IMD and GBS, the age-standardized incidence rates of other diseases in Northern Canada were 2.6-10 times higher than in the rest of Canada. Over the study period, rates decreased for IPD (p=0.04), and iGAS (p=0.01), and increased for Hi type a (Hia) (p=0.004). Among IPD cases, the proportion of pneumococcal conjugate vaccine (PCV)7 serotypes decreased (p=0.0004) over the study period. Among Hi cases, 69.8% were Hia and 71.6% of these were in children under than 5 years. Of 13 IMD cases, 8 were serogroup B and 2 of them died.

CONCLUSION

Northern population in Canada, especially infants and seniors among First Nations and Inuit, are at a high risk of IPD, Hi and iGAS. Hia is the predominant serotype in Northern Canada.

Streptococcus pneumoniae Colonization Disrupts the Microbial Community within the Upper Respiratory Tract of Aging Mice

Nasopharyngeal colonization by the Gram-positive bacterium Streptococcus pneumonia is a prerequisite for pneumonia and invasive pneumococcal diseases. Colonization is asymptomatic, involving dynamic and complex interplay between commensals, the host immune system, and environmental factors. The elderly are at an increased risk of developing pneumonia, which might be due to changes in the respiratory microbiota that would impact bacterial colonization and persistence within this niche. We hypothesized that the composition of the upper respiratory tract (URT) microbiota changes with age and subsequently can contribute to sustained colonization and inefficient clearance of S. pneumoniae To test this, we used a mouse model of pneumococcal colonization to compare the composition of the URT microbiota in young, middle-aged, and old mice in the naive state and during the course of colonization using nasal pharyngeal washes. Sequencing of variable region 3 (V3) of the 16S rRNA gene was used to identify changes occurring with age and throughout the course of S. pneumonia colonization. We discovered that age affects the composition of the URT microbiota and that colonization with S. pneumoniae is more disruptive of preexisting communities in older mice. We have further shown that host-pathogen interactions followingS. pneumonia colonization can impact the populations of resident microbes, including Staphylococcus and Haemophilus. Together, our findings indicate alterations to the URT microbiota could be detrimental to the elderly, resulting in increased colonization of S. pneumonia and decreased efficiency in its clearance.

Cost-Effectiveness of Vaccinating Immunocompetent ≥65 Year Olds with the 13-Valent Pneumococcal Conjugate Vaccine in England

BACKGROUND

Recently a large clinical trial showed that the use of 13-valent pneumococcal conjugate vaccine (PCV13) among immunocompetent individuals aged 65 years and over was safe and efficacious. The aim of this study was to assess the cost-effectiveness of vaccinating immunocompetent 65 year olds with PCV13 vaccine in England. England is a country with universal childhood pneumococcal conjugate vaccination programme in place (7-valent (PCV7) since 2006 and PCV13 since 2010), as well as a 23-valent pneumococcal polysaccharide (PPV23) vaccination programme targeting clinical risk-groups and those ≥65 years.

METHOD

A static cohort cost-effectiveness model was developed to follow a cohort of 65 year olds until death, which will be vaccinated in the autumn of 2016 with PCV13. Sensitivity analysis was performed to test the robustness of the results.

RESULTS

The childhood vaccination programme with PCV7 has induced herd protection among older unvaccinated age groups, with a resultant low residual disease burden caused by PCV7 vaccine types. We show similar herd protection effects for the 6 additional serotypes included in PCV13, and project a new low post-introduction equilibrium of vaccine-type disease in 2018/19. Applying these incidence projections for both invasive disease and community-acquired pneumonia (CAP), and using recent measures of vaccine efficacy against these endpoints for ≥65 year olds, we estimate that vaccination of a cohort of immunocompetent 65 year olds with PCV13 would directly prevent 26 cases of IPD, 69 cases of CAP and 15 deaths. The associated cost-effectiveness ratio is £257,771 per QALY gained (using list price of £49.10 per dose and £7.51 administration costs) and is therefore considered not cost-effective. To obtain a cost-effective programme the price per dose would need to be negative. The results were sensitive to disease incidence, waning vaccine protection and case fatality rate; despite this, the overall conclusion was robust.

CONCLUSIONS

Vaccinating immunocompetent individuals aged ≥65 years with PCV13 is efficacious. However the absolute incidence of vaccine-type disease will likely become very low due to wider benefits of the childhood PCV13 vaccination programme, such that a specific PCV13 vaccination programme targeting the immunocompetent elderly would not be cost-effective.

The effectiveness of pneumococcal polysaccharide vaccine 23 (PPV23) in the general population of 50 years of age and older: A systematic review and meta-analysis

Two pneumococcal vaccines currently exist and have been recommended for the prevention of pneumococcal infection in adults 65 years of age and older: the 23-valent polysaccharide (PPV23) and the conjugate 13-valent (PCV13) vaccine.

OBJECTIVE

To evaluate and summarize the results from all studies reporting on the vaccine effectiveness of PPV23 in preventing invasive pneumococcal disease (IPD) and community-acquired pneumonia (CAP) in individuals over the age of 50.

METHODS

Systematic database searches were completed in PubMed, Medline, Embase, CINAHL, Web of Science, and Cochrane. Google Scholar and hand searches of seminal articles and past systematic reviews were employed. Studies were included if they independently evaluated the effect of PPV23 on IPD and/or CAP in adults (50+). Data extraction and quality assessment were both completed independently by two researchers. Quality was assessed using the National Advisory Committee on Immunization methodology for quality assessment. All conflicts were resolved by consensus.

RESULTS

The vaccine effectiveness for PPV23 in preventing IPD was 50% (95% CI: 21%-69%) for cohort studies and 54% (95% CI: 32%-69%) for case-control studies. The VE estimates for CAP were 4% (95% CI: -26%-26%) for trials, 17% (95% CI: -26%-45%) for cohort studies, and 7% (95% CI: -10%-21%) for case-control studies.

CONCLUSIONS

The vaccine effectiveness of PPV23 in preventing IPD and all-cause CAP was consistent with past systematic reviews and similar to the estimates that were reported in the CAPiTA trial evaluating the vaccine effectiveness of PCV13. Consistent benefits were also reported across ecological studies and reports of surveillance data for the general population 50 years and older. The results suggests that the current practice of vaccinating the adults 65 years of age and older with PPV23 would have similar benefits to PCV13 in preventing potential cases of all-serotype IPD and all-cause CAP.

Host Factors and Biomarkers Associated with Poor Outcomes in Adults with Invasive Pneumococcal Disease

BACKGROUND

Invasive pneumococcal disease (IPD) causes considerable morbidity and mortality. We aimed to identify host factors and biomarkers associated with poor outcomes in adult patients with IPD in Japan, which has a rapidly-aging population.

METHODS

In a large-scale surveillance study of 506 Japanese adults with IPD, we investigated the role of host factors, disease severity, biomarkers based on clinical laboratory data, treatment regimens, and bacterial factors on 28-day mortality.

RESULTS

Overall mortality was 24.1%, and the mortality rate increased from 10.0% in patients aged ˂50 years to 33.1% in patients aged ≥80 years. Disease severity also increased 28-day mortality, from 12.5% among patients with bacteraemia without sepsis to 35.0% in patients with severe sepsis and 56.9% with septic shock. The death rate within 48 hours after admission was high at 54.9%. Risk factors for mortality identified by multivariate analysis were as follows: white blood cell (WBC) count <4000 cells/μL (odds ratio [OR], 6.9; 95% confidence interval [CI], 3.7-12.8, p < .001); age ≥80 years (OR, 6.5; 95% CI, 2.0-21.6, p = .002); serum creatinine ≥2.0 mg/dL (OR, 4.5; 95% CI, 2.5-8.1, p < .001); underlying liver disease (OR, 3.5; 95% CI, 1.6-7.8, p = .002); mechanical ventilation (OR, 3.0; 95% CI, 1.7-5.6, p < .001); and lactate dehydrogenase ≥300 IU/L (OR, 2.4; 95% CI, 1.4-4.0, p = .001). Pneumococcal serotype and drug resistance were not associated with poor outcomes.

CONCLUSIONS

Host factors, disease severity, and biomarkers, especially WBC counts and serum creatinine, were more important determinants of mortality than bacterial factors.

Consensus Recommendation for India and Bangladesh for the Use of Pneumococcal Vaccine in Mass Gatherings with Special Reference to Hajj Pilgrims

Respiratory tract infections are prevalent among Hajj pilgrims with pneumonia being a leading cause of hospitalization. Streptococcus pneumoniae is a common pathogen isolated from patients with pneumonia and respiratory tract infections during Hajj. There is a significant burden of pneumococcal disease in India, which can be prevented. Guidelines for preventive measures and adult immunization have been published in India, but the implementation of the guidelines is low. Data from Bangladesh are available about significant mortality due to respiratory infections; however, literature regarding guidelines for adult immunization is limited. There is a need for extensive awareness programs across India and Bangladesh. Hence, there was a general consensus about the necessity for a rapid and urgent implementation of measures to prevent respiratory infections in pilgrims traveling to Hajj. About ten countries have developed recommendations for pneumococcal vaccination in Hajj pilgrims: France, the USA, Kuwait, Qatar, Bahrain, the UAE (Dubai Health Authority), Singapore, Malaysia, Egypt, and Indonesia. At any given point whether it is Hajj or Umrah, more than a million people are present in the holy places of Mecca and Madina. Therefore, the preventive measures taken for Hajj apply for Umrah as well. This document puts forward the consensus recommendations by a group of twenty doctors following a closed-door discussion based on the scientific evidence available for India and Bangladesh regarding the prevention of respiratory tract infections in Hajj pilgrims.

Pneumococcal conjugate vaccine use in adults

Streptococcus pneumoniae is a leading cause of illness and death in adults. A polysaccharide vaccine has been available for over 30 years, but despite significant use, the public health impact of this vaccine has been limited. The 13-valent pneumococcal conjugate vaccine (PCV13) has been licensed by the US Food and Drug Administration and other international regulatory authorities with the assumption that induction of a T cell-dependent immune response and noninferior immunogenicity to vaccine antigens when compared with the polysaccharide vaccine would be important to satisfy a significant unmet medical need. PCV13 efficacy against vaccine-type pneumococcal community-acquired pneumonia was confirmed in a large randomized controlled trial in older adults and its use is now increasingly recommended globally.

The Influence of Influenza and Pneumococcal Vaccines on Community-Acquired Pneumonia (CAP) Outcomes Among Elderly Patients

Elderly are at high risk for hospitalization for community-acquired pneumonia (CAP), especially due to Streptococcus pneumoniae, and seasonal influenza viruses. Data suggest PPV23's influence on various CAP-related outcomes among the elderly may depend upon how many years have elapsed since they received this vaccine. PPV23's protection against invasive pneumococcal disease and CAP hospitalizations are often limited to moderately ill elderly, who are less than 75 years old, or female. PCV13 demonstrates broad protection against a variety of CAPs, but ultimately, its influence on their outcomes among the elderly may be limited by herd immunity from PCV7 use. Influenza vaccine's indirect protective effect against all-cause and non-invasive pneumococcal CAP in the elderly is difficult to ascertain. The use of both PPV23 and influenza vaccine shortens length of stay in hospitalized elderly with CAP, but whether that benefit would be realized in the presence of herd immunity is unknown.

Prevention of pneumococcal infections during mass gathering

The interest in mass gathering and its implications has been increasing due to globalization and international travel. The potential occurrence of infectious disease outbreaks during mass gathering is most feared. In this context, respiratory tract infections are of great concern due to crowding in a limited space which facilitates and magnifies the potential of disease spread among attendees. Pneumococcal disease is best described among pilgrims to Makkah and vaccination is one of the methods for the prevention of this disease. Pneumonia was described in a mass gathering with a prevalence of 4.8/100,000 pilgrims and contributes to 15-39% of hospitalizations. Various studies showed that 7-37% of pilgrims are 65 y of age or older. The uptake of pneumococcal vaccine among pilgrims is low at 5%. There is no available data to make strong recommendations for S. pneumoniae vaccination of all pilgrims, it is important that a high risk population receive the indicated vaccination. We reviewed the available literature on the burden of pneumococcal infections during mass gathering and evaluate the available literature on pneumococcal vaccinations for attendees of mass gathering.