The burden of PCV13 serotypes in hospitalized pneumococcal pneumonia in Spain using a novel urinary antigen detection test. CAPA study

Treatment Failure and Clinical Stability in Severe Community-Acquired Pneumonia

Treatment failure and clinical stability are important outcomes in community-acquired pneumonia (CAP). It is essential to know the causes and risk factors for treatment failure and delay in reaching clinical stability in CAP. The study of both as well as the associated underlying mechanisms and host response are key to improving outcomes in pneumonia.

Pneumococcal Serotypes Associated with Community-Acquired Pneumonia Hospitalizations in Adults in Spain, 2016-2020: The CAPA Study

Newer higher valency pneumococcal conjugate vaccines (PCVs) have the potential to reduce the adult community-acquired pneumonia (CAP) burden. We describe the evolution and distribution of adult community-acquired pneumonia (CAP) serotypes in Spain, focusing on serotypes contained in the 20-valent PCV (PCV20). This was a prospective, observational study of chest X-ray (CXR)-confirmed CAP in immunocompetent adults hospitalized in one of four Spanish hospitals between November 2016 and November 2020. Pneumococci were isolated from cultures and detected in urine using BinaxNow® and Pfizer serotype-specific urinary antigen tests UAD1 and UAD2. We included 1948 adults hospitalized with CXR-CAP. The median age was 69.0 years (IQR: 24 years). At least one comorbidity was present in 84.8% (n = 1653) of patients. At admission, 76.1% of patients had complicated pneumonia. Pneumococcus was identified in 34.9% (n = 680) of study participants. The PCV20 vaccine-type CAP occurred in 23.9% (n = 465) of all patients, 68.4% (n = 465) of patients with pneumococcal CAP, and 82.2% (83/101) of patients who had pneumococcus identified by culture. Serotypes 8 (n = 153; 7.9% of all CAP) and 3 (n = 152; 7.8% of all CAP) were the most frequently identified. Pneumococcus is a common cause of hospitalized CAP among Spanish adults and serotypes contained in PCV20 caused the majority of pneumococcal CAP.

The remarkable history of pneumococcal vaccination: an ongoing challenge

Although it varies with age and geographical distribution, the global burden of infection with Streptococcus pneumoniae (pneumococcus) remains considerable. The elderly, and younger adults with comorbid conditions, are at particularly high risk of pneumococcal infection, and this risk will increase as the population ages. Vaccination should be the backbone of our current strategies to deal with this infection.

Main body: This manuscript reviews the history of the development of pneumococcal vaccines, and the impact of different vaccines and vaccination strategies over the past 111 years. It documents the early years of vaccine development in the gold mines of South Africa, when vaccination with killed pneumococci was shown to be effective, even before the recognition that different pneumococci were antigenically distinct. The development of type-specific vaccines, still with whole killed pneumococci, showed a high degree of efficacy. The identification of the importance of the pneumococcal capsule heralded the era of vaccination with capsular polysaccharides, although with the advent of penicillin, interest in pneumococcal vaccine development waned. The efforts of Austrian and his colleagues, who documented that despite penicillin therapy, patients still died from pneumococcal infection in the first 96 h, ultimately led to the licensing first of a 14-valent pneumococcal polysaccharide in 1977 followed by the 23-valent pneumococcal polysaccharide in 1983. The principal problem with these, as with other polysaccharide vaccines, was that that they failed to immunize infants and toddlers, who were at highest risk for pneumococcal disease. This was overcome by chemical linking or conjugation of the polysaccharide molecules to an immunogenic carrier protein. Thus began the era of pneumococcal conjugate vaccine (PCV), starting with PCV7, progressing to PCV10 and PCV13, and, most recently, PCV15 and PCV20. However, these vaccines remain serotype specific, posing the challenge of new serotypes replacing vaccine types. Current research addresses serotype-independent vaccines which, so far, has been a challenging and elusive endeavor.

Conclusion: While there has been enormous progress in the development of pneumococcal vaccines during the past century, attempts to develop a vaccine that will retain its efficacy for most pneumococcal serotypes are ongoing.

Non-invasive pneumococcal pneumonia due to vaccine serotypes: A systematic review and meta-analysis

BACKGROUND

Non-invasive pneumococcal pneumonia causes significant morbidity and mortality in older adults. Understanding pneumococcal sero-epidemiology in adults ≥50 years is necessary to inform vaccination policies and the updating of pneumococcal vaccines.

METHODS

We conducted a systematic review and random-effects meta-analysis to determine the proportion of community-acquired pneumonia (CAP) in people ≥50 years due to pneumococcus and the proportion caused by pneumococcal vaccine serotypes. We searched MEDLINE, EMBASE and PubMed from 1 January 1990 to 30 March 2021. Heterogeneity was explored by subgroup analysis according to a) patient group (stratified versus age) and depth of testing, b) detection/serotyping method, and c) continent. The protocol is registered with PROSPERO (CRD42020192002).

FINDINGS

Twenty-eight studies were included (34,216 patients). In the period 1-5 years after introduction of childhood PCV10/13 immunisation, 18% of CAP cases (95% CI 13-24%) were attributable to pneumococcus, with 49% (43-54%) of pneumococcal CAP due to PCV13 serotypes. The estimated proportion of pneumococcal CAP was highest in one study that used 24-valent serotype-specific urinary-antigen detection (ss-UAD)(30% [28-31%]), followed by studies based on diagnostic serology (28% [24-33%]), PCR (26% [15-37%]), ss-UAD14 (17% [13-22%]), and culture alone (14% [10-19%]). A higher estimate was observed in Europe (26% [21-30%] than North America (11% [9-12%](p<0·001). PCV13-serotype estimates were also influenced by serotyping methods.

INTERPRETATION

Non-invasive pneumococcal CAP and vaccine-type pneumococcal CAP remains a burden in older adults despite widespread introduction of pneumococcal infant immunisation. Studies heavily reliant on ss-UADs restricted to vaccine-type serotypes may overestimate the proportion of potentially vaccine-preventable pneumococcal pneumonia. Sero-epidemiological data from low-income countries are lacking.

The Evolution and Distribution of Pneumococcal Serotypes in Adults Hospitalized With Community-Acquired Pneumonia in Spain Using a Serotype-Specific Urinary Antigen Detection Test: The CAPA Study, 2011-2018

Background

Spain introduced the 13-valent pneumococcal conjugate vaccine (PCV13) in the childhood National Immunization Program in 2015–2016 with coverage of 3 doses of 94.8% in 2018. We assessed the evolution of all pneumococcal, PCV13 vaccine type (VT), and experimental PCV20-VT (PCV13 + serotypes 8, 10A, 11A, 12F, 15B, 22F, 33F) hospitalized community-acquired pneumonia (CAP) in adults in Spain from 2011–2018.

Methods

A prospective observational study of immunocompetent adults (≥18 years) admitted to 4 Spanish hospitals with chest X-ray–confirmed CAP between November 2011 and November 2018. Microbiological confirmation was obtained using the Pfizer serotype-specific urinary antigen detection tests (UAD1/UAD2), BinaxNow test for urine, and conventional cultures of blood, pleural fluid, and high-quality sputum.

Results

Of 3107 adults hospitalized with CAP, 1943 were ≥65 years. Underlying conditions were present in 87% (n = 2704) of the participants. Among all patients, 895 (28.8%) had pneumococcal CAP and 439 (14.1%) had PCV13-VT CAP, decreasing from 17.9% (n = 77) to 13.2% (n = 68) from 2011–2012 to 2017–2018 (P = .049). PCV20-VT CAP occurred in 243 (23.8%) of those included in 2016–2018. The most identified serotypes were 3 and 8. Serotype 3 accounted for 6.9% (n = 215) of CAP cases, remaining stable during the study period, and was associated with disease severity.

Conclusions

PCV13-VT caused a substantial proportion of CAP in Spanish immunocompetent adults 8 years after introduction of childhood PCV13 immunization. Improving direct PCV13 coverage of targeted adult populations could further reduce PCV13-VT burden, a benefit that could be increased further if PCV20 is licensed and implemented.

Burden of pneumococcal disease among adults in Southern Europe (Spain, Portugal, Italy, and Greece): a systematic review and meta-analysis

The aim was to summarize pneumococcal disease burden data among adults in Southern Europe and the potential impact of vaccines on epidemiology. Of 4779 identified studies, 272 were selected. Invasive pneumococcal disease (IPD) incidence was 15.08 (95% CI 11.01-20.65) in Spain versus 2.56 (95% CI 1.54-4.24) per 100,000 population in Italy. Pneumococcal pneumonia incidence was 19.59 (95% CI 10.74-35.74) in Spain versus 2.19 (95% CI 1.36-3.54) per 100,000 population in Italy. Analysis of IPD incidence in Spain comparing pre-and post- PCV7 and PCV13 periods unveiled a declining trend in vaccine-type IPD incidence (larger and statistically significant for the elderly), suggesting indirect effects of childhood vaccination programme. Data from Portugal, Greece and, to a lesser extent, Italy were sparse, thus improved surveillance is needed. Pneumococcal vaccination uptake, particularly among the elderly and adults with chronic and immunosuppressing conditions, should be improved, including shift to a higher-valency pneumococcal conjugate vaccine when available.

Epidemiology of community-acquired pneumonia in the era of extended serotype-covering multivalent pneumococcal conjugate vaccines

BACKGROUND

South Korea has been providing 10-valent pneumococcal conjugate vaccine/(PCV10)/13-valent pneumococcal conjugate vaccine (PCV13) to children and 23-valent pneumococcal polysaccharide vaccine (PPSV23) to older adults as part of a national immunization program.

METHODS

From September 2015 to August 2017, a prospective cohort study was conducted for adults aged ≥19 years with community-acquired pneumonia (CAP) at four university hospitals. All-cause and pneumococcal CAP incidence and mortality rates were evaluated on the basis of hospital catchment population. Serotype distribution of pneumococcal CAP was also evaluated.

RESULTS

Among 2669 patients with CAP, 252 cases (9.4%) were pneumococcal CAP cases. The annual incidences of all-cause and pneumococcal CAP were 194.3 cases and 18.3 cases respectively, per 100,000 persons. Serotyped Streptococcus pneumoniae was identified in 107 cases (42.5%) through culture or a serotype-specific urinary antigen detection assay. Pneumococcal CAP caused by the PCV13 and PPSV23 serotypes were 50 cases (46.7% of serotyped pneumococcal CAP and 19.8% of pneumococcal CAP), and 83 cases (77.6% of serotyped pneumococcal CAP and 32.9% of pneumococcal CAP), respectively. The most prevalent serotype was 3 (n = 21, 19.6% of serotyped pneumococcal CAP), followed by 19A (n = 10, 9.3% of serotyped pneumococcal CAP) and 11A (n = 10, 9.3% of serotyped pneumococcal CAP). Compared with non-pneumococcal CAP patients, pneumococcal CAP patients were more likely to have a higher CURB-65 scores (P = 0.002). The overall 30-day mortality rate of pneumococcal CAP was higher than that of non-pneumococcal CAP (6.3% versus 5.6%; odds ratio [OR], 1.15; 95% confidence interval [CI], 0.67-1.96), but this trend was reversed in patients aged 65-74 years (4.2% versus 8.6%; OR, 0.47; 95% CI, 0.14-1.54).

CONCLUSIONS

The disease burden of PCV13-serotype pneumococcal CAP remains significantly high in Korean adults, particularly among elderly people, even after a high uptake of pediatric PCVs.

Smoking Cessation/Vaccinations

More than one-third of patients with chronic obstructive pulmonary disease (COPD) continue to smoke cigarettes despite knowing they have the disease. This behavior has a negative impact on prognosis and progression, as repeated injury enhances the pathobiological mechanisms responsible for the disease. A combination of counseling plus pharmacotherapy is the most effective cessation treatment of smokers with COPD, and varenicline seems to be the most effective pharmacologic intervention. Preventing exacerbations in patients with COPD is a major goal of treatment, and vaccination against influenza and pneumococcus is an effective preventive strategy to achieve this goal.

Healthcare-associated pneumonia: a prospective study in Spain

Objective

The aim of the study was to describe the epidemiological characteristics and factors related to outcome in Streptococcus pneumoniae and methicillin-resistant Staphylococcus aureus (MRSA) healthcare-associated pneumonia (HCAP).

Patients and method

A 3-year prospective observational epidemiological case study of HCAP was conducted in seven Spanish hospitals. Microbiological and patient characteristics and outcomes were collected and classified by causative pathogen into 4 categories: “S. pneumoniae”, “MRSA”, “Others” and “Unknown”. Patients were followed up 30 days after discharge.

Results

A total of 258 (84.6%) patients were enrolled (170 were men [65.9%]). Mean age was 72.4 years ± 15 years (95% CI [70.54-74.25]). The etiology of pneumonia was identified in 73 cases (28.3%):S. pneumoniae in 35 patients (13.6%), MRSA in 8 (3.1%), and other microorganisms in 30 patients (11.6%). Significant differences in rates of chronic obstructive pulmonary disease (p < 0.05), previous antibiotic treatment (p < 0.05), other chronic respiratory diseases, inhaled corticosteroids (p < 0.01), and lymphoma (p < 0.05) were observed among the four groups. Patients with MRSA pneumonia had received more previous antibiotic treatment (87.5%). Thirty-three (12.8%) patients died during hospitalisation; death in 27 (81.2%) was related to pneumonia.

Conclusions

The etiology of HCAP was identified in only one quarter of patients, with S. pneumoniae being the most prevalent microorganism. Patients with chronic respiratory diseases more frequently presented HCAP due to MRSA than to S. pneumoniae. Death at hospital discharge was related in most cases to pneumonia.

Recent advances in the epidemiology and prevention of Streptococcus pneumoniae infections

The introduction of pneumococcal conjugate vaccines (PCVs) 7 and 13 into national childhood immunization programs in the US in 2000 and 2010, respectively, proved to be remarkably successful in reducing infant mortality due to invasive pneumococcal disease (IPD), resulting in widespread uptake of these vaccines. Secondary herd protection of non-vaccinated adults against IPD has proven to be an additional public health benefit of childhood immunization with PCVs, particularly in the case of the vulnerable elderly who are at increased risk due to immunosenescence and underlying comorbidity. Despite these advances in pneumococcal immunization, the global burden of pneumococcal disease, albeit of unequal geographic distribution, remains high. Reasons for this include restricted access of children living in many developing countries to PCVs, the emergence of infection due to non-vaccine serotypes of the pneumococcus, and non-encapsulated strains of the pathogen. Emerging concerns affecting the elderly include the realization that herd protection conferred by the current generation of PCVs (PCV7, PCV10, and PCV13) has reached a ceiling in many countries at a time of global population aging, compounded by uncertainty surrounding those immunization strategies that induce optimum immunogenicity and protection against IPD in the elderly. All of the aforementioned issues, together with a consideration of pipeline and pending strategies to improve access to, and serotype coverage of, PCVs, are the focus areas of this review.

Burden of Community-Acquired Pneumonia and Unmet Clinical Needs

Community-acquired pneumonia (CAP) is the leading cause of death among infectious diseases and an important health problem, having considerable implications for healthcare systems worldwide. Despite important advances in prevention through vaccines, new rapid diagnostic tests and antibiotics, CAP management still has significant drawbacks. Mortality remains very high in severely ill patients presenting with respiratory failure or shock but is also high in the elderly. Even after a CAP episode, higher risk of death remains during a long period, a risk mainly driven by inflammation and patient-related co-morbidities. CAP microbiology has been altered by new molecular diagnostic tests that have turned viruses into the most identified pathogens, notwithstanding uncertainties about the specific role of each virus in CAP pathogenesis. Pneumococcal vaccines also impacted CAP etiology and thus had changed Streptococcus pneumoniae circulating serotypes. Pathogens from specific regions should also be kept in mind when treating CAP. New antibiotics for CAP treatment were not tested in severely ill patients and focused on multidrug-resistant pathogens that are unrelated to CAP, limiting their general use and indications for intensive care unit (ICU) patients. Similarly, CAP management could be personalized through the use of adjunctive therapies that showed outcome improvements in particular patient groups. Although pneumococcal vaccination was only convincingly shown to reduce invasive pneumococcal disease, with a less significant effect in pneumococcal CAP, it remains the best therapeutic intervention to prevent bacterial CAP. Further research in CAP is needed to reduce its population impact and improve individual outcomes.

Community-Acquired Pneumonia. Spanish Society of Pulmonology and Thoracic Surgery (SEPAR) Guidelines. 2020 Update

The guidelines for community-acquired pneumonia, last published in 2010, have been updated to provide recommendations based on a critical summary of the latest literature to help health professionals make the best decisions in the care of immunocompetent adult patients. The methodology was based on 6 PICO questions (on etiological studies, assessment of severity and decision to hospitalize, antibiotic treatment and duration, and pneumococcal conjugate vaccination), agreed by consensus among a working group of pulmonologists and an expert in documentation science and methodology. A comprehensive review of the literature was performed for each PICO question, and these were evaluated in in-person meetings. The American Thoracic Society guidelines were published during the preparation of this paper, so the recommendations of this association were also evaluated. We concluded that the etiological source of the infection should be investigated in hospitalized patients who have suspected resistance or who fail to respond to treatment. Prognostic scales, such as PSI, CURB 65, and CRB65, are useful for assessing severity and the decision to hospitalize. Different antibiotic regimens are indicated, depending on the treatment setting - outpatient, hospital, or intensive care unit - and the resistance of PES microorganisms should be calculated. The minimum duration of antibiotic treatment should be 5 days, based on criteria of clinical stability. Finally, we reviewed the indication of the 13-valent conjugate vaccine in immunocompetent patients with risk factors and comorbidity.

Clinical Relevance and Molecular Pathogenesis of the Emerging Serotypes 22F and 33F of Streptococcus pneumoniae in Spain

Streptococcus pneumoniae is the main bacterial cause of respiratory infections in children and the elderly worldwide. Serotype replacement is a frequent phenomenon after the introduction of conjugated vaccines, with emerging serotypes 22F and 33F as frequent non-PCV13 serotypes in children and adults in North America and other countries. Characterization of mechanisms involved in evasion of the host immune response by these serotypes is of great importance in public health because they are included in the future conjugated vaccines PCV15 and PCV20. One of the main strategies of S. pneumoniae to persistently colonize and causes infection is biofilm formation. In this study, we have evaluated the influence of capsule polysaccharide in biofilm formation and immune evasion by using clinical isolates from different sources and isogenic strains with capsules from prevalent serotypes. Since the introduction of PCV13 in Spain in the year 2010, isolates of serotypes 22F and 33F are rising among risk populations. The predominant circulating genotypes are ST433^22F and ST717^33F, being CC433 in 22F and CC717 in 33F the main clonal complexes in Spain. The use of clinical isolates of different origin, demonstrated that pediatric isolates of serotypes 22F and 33F formed better biofilms than adult isolates and this was statistically significant. This phenotype was greater in clinical isolates from blood origin compared to those from cerebrospinal fluid, pleural fluid and otitis. Opsonophagocytosis assays showed that serotype 22F and 33F were recognized by the PSGL-1 receptor on leukocytes, although serotype 22F, was more resistant than serotype 33F to phagocytosis killing and more lethal in a mouse sepsis model. Overall, the emergence of additional PCV15 serotypes, especially 22F, could be associated to an enhanced ability to divert the host immune response that markedly increased in a biofilm state. Our findings demonstrate that pediatric isolates of 22F and 33F, that form better biofilm than isolates from adults, could have an advantage to colonize the nasopharynx of children and therefore, be important in carriage and subsequent dissemination to the elderly. The increased ability of serotype 22F to avoid the host immune response, might explain the emergence of this serotype in the last years.

Pneumococcal conjugate serotype distribution and predominating role of serotype 3 in German adults with community-acquired pneumonia

INTRODUCTION

Implementation of the 7-valent pneumococcal conjugate vaccine (PCV7) in infant vaccination programs has substantially reduced the burden of PCV7 serotypes also in adult community-acquired pneumonia (CAP). Currently, it is unclear, if this extensive herd protection effect can be extrapolated to the additional 6 serotypes included in the 13-valent pneumococcal conjugate vaccine (PCV13), which replaced PCV7 in Germany in 2010.

OBJECTIVES

We investigated changing trends for PCV13 serotypes in adult CAP patients between three to seven years after implementation of PCV13 infant immunization in Germany.

METHODS

Between December 2012 and January 2017, urine samples from German adult patients with radiologically confirmed CAP were prospectively collected by the multi-center cohort study CAPNETZ and analyzed by the serotype-specific multiplex urinary antigen detection assay (SSUAD) allowing for the detection of PCV13 serotypes.

RESULTS

PCV13 serotypes were found in 59 of 796 (7.4%) patients with all-cause CAP, most prevalent was serotype 3 (30 of 59 patients, 50.8%). All patients with serotype 3-CAP were admitted to hospital and the majority required oxygen at admission (83.3% of patients with serotype 3-CAP versus 50.9% of patients with pneumococcal CAP by other serotypes, p = 0.005). Compared to SSUAD testing, conventional microbiological workup missed 27 of 30 (90.0%) serotype 3-CAP cases. We could not observe a time trend in the proportions of PCV13 serotypes and serotype 3 in all-cause CAP between 2013 and 2016 (OR trend per year 0.84, 95% CI 0.64-1.11 for PCV13 serotypes and OR trend per year 0.95, 95% CI 0.70-1.28 for serotype 3).

CONCLUSIONS

Conventional methods underestimate serotype 3-CAP that can cause severe disease. Changes in overall PCV13 coverage were not detected during the years 2013 to 2016, mostly driven by a high proportion of serotype 3.

Identification of Pneumococcal Serotypes by PCR-Restriction Fragment Length Polymorphism

Streptococcus pneumoniae shows more than 90 capsular serotypes that can be distinguished by their reactivity against antisera. The main objective of this work was the development of a molecular method for serotyping without the use of antisera. A computer program containing an algorithm was used to search in a database for potentially useful enzymes for Restriction Fragment Length Polymorphism-RFLP typing, in order to maximize the discrimination between different serotypes. DNA sequences of 90 serotypes for the region between dexB and aliA genes were compiled, and a computer screening of restriction enzymes was performed. The wzg–wzh–wzd–wze region and Sse9I restriction predicted unique PCR-RFLP patterns for 39 serotypes and eight serogroups. A second restriction enzyme resolved fragment specific patterns for 25 serotypes. The method was tested with 98 serotype-unknown clinical isolates. PCR-RFLP analysis deduced correct serotypes that were confirmed by Quellung reaction for 78.5% of the isolates.

Differences between diabetic and non-diabetic patients with community-acquired pneumonia in primary care in Spain

BACKGROUND

Diabetes is one of the underlying risk factors for developing community-acquired pneumonia (CAP). The high prevalence of diabetes among population and the rising incidence of this illness, converts it as an important disease to better control and manage, to prevent its secondary consequences as CAP. The objective of this research is to describe the characteristics of the patients with diabetes and the differences with the no diabetes who have had an episode of CAP in the context of the primary care field.

METHODS

A retrospective, observational study in adult patients (> 18 years-old) who suffer from CAP and attended at primary care in Spain between 2009 and 2013 was developed using the Computerized Database for Pharmacoepidemiological Studies in Primary Care (BIFAP). We carried out a descriptive analysis of the first episodes of CAP, in patients with or without diabetes as comorbidity. Other morbidity (CVA, Anaemia, Arthritis, Asthma, Heart disease, Dementia, Depression, Dysphagia, Multiple sclerosis, Epilepsy, COPD, Liver disease, Arthrosis, Parkinson's disease, Kidney disease, HIV) and life-style factors were also included in the study.

RESULTS

A total of 51,185 patients were included in the study as they suffer from the first episode of CAP. Of these, 8012 had diabetes as comorbidity. There were differences between sex and age in patients with diabetes. Patients without diabetes were younger, and had less comorbidities including those related to lifestyles such as smoking, alcoholism, social and dental problems than patients with diabetes.

CONCLUSIONS

Patients who developed an episode of CAP with diabetes have more risk factors which could be reduced with an appropriate intervention, including vaccination to prevent successive CAP episodes and hospitalization. The burden of associated factors in these patients can produce an accumulation of risk. Health care professional should know this for treating and control these patients in order to avoid complications. Diabetes and those other risk factors associated could be reduced with an appropriate intervention, including vaccination to prevent the first and successive CAP episodes and the subsequent hospitalization in severe cases.

Development for Clinical Use of a Multiplexed Immunoassay Using Sputum Samples for Streptococcus pneumoniae: a Non-Culture-Based Approach for Serotype-Specific Detection

The multiplexed immunoassay (MIA) is an automated, monoclonal antibody-based serotyping assay that uses culture lysates of Streptococcus pneumoniae This study describes the development and validation of applying MIA directly to sputum samples for the serotype-specific detection of S. pneumoniae Sputum optimization involved liquefaction and fractionation. The subjects included 173 adult patients from whom both pneumococcal isolates cultured from sputum samples and the corresponding sputum samples were available at the Korea University Hospital from March 2012 to June 2015. Pneumococcal lysates and the sputum fraction were separately evaluated by MIA with a set A reaction to identify 27 serotypes (24 vaccine serotypes and serotypes 6C, 6D, and 11E). MIA results were validated by multiplex PCR (mPCR). Among the 173 patients analyzed, the pneumococcal isolate MIA detected a single set A serotype in 104 patients, and the corresponding sputum MIA showed concordant results with additional multiple serotypes in 21 patients. For the remaining 69 patients whose pneumococcal isolates were not determined to be set A serotypes by the pneumococcal isolate MIA, the corresponding sputum MIA identified additional set A serotypes (single serotypes, n = 17; multiple serotypes, n = 4). Serotypes 3 and 11A/D/F were the most commonly detected serotypes in both the pneumococcal isolate and sputum MIA analyses. However, serotype 8 was the most prevalent serotype detected only by the sputum MIA. The results of mPCR, performed for validation, showed a high concordance with the results of the sputum MIA. In conclusion, MIA using sputum samples enables the accurate, rapid, direct, and serotype-specific detection of S. pneumoniae, which may improve postvaccination serotype surveillance.

Optimal approaches to preventing severe community-acquired pneumonia

Introduction: Community-acquired pneumonia (CAP) has the highest rate of mortality of all infectious diseases, especially among the elderly. Severe CAP (sCAP) is defined as a CAP in which intensive care management is required and is associated with an unfavorable clinical course. Areas covered: This review aims to identify prevention strategies for reducing the incidence of CAP and optimized management of sCAP. We highlight the main prevention approaches for CAP, focusing on the latest vaccination plans and on the influence of health-risk behaviors. Lastly, we report the latest recommendations about the optimal approach for sCAP when CAP has already been diagnosed, including prompt admission to ICU, early empirical antibiotic therapy, and optimization of antibiotic use. Expert opinion: Despite improvements in the diagnosis and treatment of sCAP, more efforts are needed to combat preventable causes, including the implementation and improvement of vaccine coverage, anti-tobacco campaigns and correct oral hygiene. Moreover, future research should aim to assess the benefits of early antimicrobial therapy in primary care. Pharmacokinetic studies in the target population may help clinicians to adjust dosage regimens in critically ill patients with CAP and thus reduce rates of treatment failure.

TIPICO IX: report of the 9th interactive infectious disease workshop on infectious diseases and vaccines

The Ninth Interactive Infectious Disease workshop TIPICO was held on November 22–23, 2018, in Santiago de Compostela, Spain. This 2-day academic experience addressed current and topical issues in the field of infectious diseases and vaccination. Summary findings of the meeting include: cervical cancer elimination will be possible in the future, thanks to the implementation of global vaccination action plans in combination with appropriate screening interventions. The introduction of appropriate immunization programs is key to maintain the success of current effective vaccines such as those against meningococcal disease or rotavirus infection. Additionally, reduced dose schedules might improve the efficiency of some vaccines (i.e., PCV13). New vaccines to improve current preventive alternatives are under development (e.g., against tuberculosis or influenza virus), while others to protect against infectious diseases with no current available vaccines (e.g., enterovirus, parechovirus and flaviviruses) need to be developed. Vaccinomics will be fundamental in this process, while infectomics will allow the application of precision medicine. Further research is also required to understand the impact of heterologous vaccine effects. Finally, vaccination requires education at all levels (individuals, community, healthcare professionals) to ensure its success by helping to overcome major barriers such as vaccine hesitancy and false contraindications.

Effectiveness of the 13-valent pneumococcal conjugate vaccine against adult pneumonia in Italy: a case-control study in a 2-year prospective cohort

OBJECTIVES

Current strategies to prevent adult pneumococcal disease have been recently reviewed in Italy. We did a postlicensure study to estimate the direct vaccine effectiveness (VE) of the 13-valent pneumococcal conjugate vaccine (PCV13) against adult pneumococcal community-acquired pneumonia (pCAP).

STUDY DESIGN

Between 2013 and 2015, a 2-year prospective cohort study of adults with CAP was conducted in the Apulia region of Italy where the average vaccine uptake of PCV13 was 32% among adults ≥65 years. The test-negative design was used to estimate VE against all episodes of confirmed pCAP and vaccine-type (VT)-CAP. VE in a subgroup of patients managed in the community was also estimated using a matched case-control design. VE was calculated as one minus the OR times 100%.

RESULTS

The overall VE of PCV13 was 33.2% (95% CI -106.6% to 82%) against pCAP irrespective of serotype and 38.1% (95% CI -131.9% to 89%) against VT-CAP in the cohort of adults ≥65 years. The VE was 42.3% (95% CI -244.1% to 94.7%) against VT-CAP in the age group at higher vaccine uptake. For the subgroup of cases managed in the community, the overall VE against disease due to any pneumococcal strain was 88.1% (95% CI 4.2% to 98.5%) and 91.7% (95% CI 13.1% to 99.2%) when we controlled for underlying conditions.

CONCLUSIONS

Although our results are non-significant, PCV13 promises to be effective against all confirmed pCAP already with modest levels of uptake in the population of adults ≥65 years of age. Larger studies are needed to confirm the direct vaccine benefits.

The Evolving Epidemiology of Serotype Distribution and Antimicrobial Resistance of Streptococcus pneumoniae Strains Isolated from Adults in Crete, Greece, 2009-2016

Background

Pneumococcal disease is a major cause of morbidity and mortality worldwide, especially in patients with comorbidities and advanced age. This study evaluated trends in epidemiology of adult pneumococcal disease in Crete, Greece, by identifying serotype distribution and antimicrobial resistance of consecutive Streptococcus pneumoniae strains isolated from adults during an 8-year time period (2009–2016) and the indirect effect of the infant pneumococcal higher-valent conjugate vaccines 10-valent pneumococcal conjugate vaccine (PCV10) and 13-valent pneumococcal conjugate vaccine (PCV13).

Materials and Methods

Antimicrobial susceptibility was performed by E-test and serotyping by Quellung reaction. Multidrug resistance (MDR) was defined as non-susceptibility to penicillin (PNSP) combined with resistance to ≥2 non-β-lactam antimicrobials.

Results

A total of 135 S. pneumoniae strains were isolated from adults during the study period. Twenty-one serotypes were identified with 17F, 15A, 3, 19A, and 11A, being the most common. The coverage rates of PCV10, and PCV13 were 17.8% and 37.8%, respectively. PCV13 serotypes decreased significantly from 68.4% in 2009 to 8.3% in 2016 (P = 0.002). The most important emerging non-PCV13 serotypes were 17F, 15A, and 11A, with 15A being strongly associated with antimicrobial resistance and MDR. Among all study isolates, penicillin-resistant and MDR strains represented 7.4% and 14.1%, respectively. Predominant PNSP serotypes were 19A (21.7%), 11A (17.4%), and 15A (17.4%). Erythromycin, clindamycin, tetracycline, trimethoprim-sulfamethoxazole, and levofloxacin resistant rates were 30.4%, 15.6%, 16.3%, 16.3%, and 1.5%, respectively.

Conclusion

Although pneumococcal disease continues to be a health burden in adults in Crete, our study reveals a herd protection effect of the infant pneumococcal higher-valent conjugate vaccination. Surveillance of changes in serotype distribution and antimicrobial resistance among pneumococcal isolates are necessary to guide optimal prevention and treatment strategies.