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Invasive pneumococcal infection is a major cause of morbidity and mortality worldwide despite the availability of pneumococcal vaccines. The aim of this study was to re-evaluate the clinical syndromes, prognostic factors and outcomes for pneumococcal disease in adults and children in Singapore during the period before and after the introduction of the pneumococcal vaccine. We retrospectively analyzed a large cohort of patients admitted to the four main public hospitals in Singapore with S. pneumoniae infection between 1997 and 2013. A total of 889 (64% of all isolates identified in the clinical laboratories) cases were included in the analysis; 561 (63.1%) were adult (≥16 years) cases with a median age of 62 years and 328 (36.9%) were paediatric cases with a median age of 3 years. Bacteraemic pneumonia was the most common syndrome in both groups (69.3% vs. 44.2%), followed by primary bacteraemia without pneumonia (14.3% vs. 13.4%), meningitis (6.4% vs. 7.6%) and non-bacteraemic pneumonia (5.2% vs. 21%). The major serotypes in adults were 3, 4, 6B, 14, 19F and 23F whereas in children they were 14, 6B and 19F, accounting both for nearly half of pneumococcal disease cases. No particular serotype was associated with mortality or severity of the pneumococcal disease. Overall mortality rate was 18.5% in adults and 3% in children. Risk factors for mortality included acute cardiac events in adults, meningitis in children and critical illness and bilateral pulmonary infiltrates in both adults and children. Penicillin resistance was not associated with increased mortality. Our results agree with global reports that the course of pneumococcal disease and its clinical outcome were more severe in adults than in children. The main serotypes causing invasive disease were mostly covered by the vaccines in use. The high mortality rates reflect an urgent need to increase vaccination coverage in both adults and children to tackle this vaccine-preventable infection., Competing Interests: OTN has received a grant from the Healthcare cluster and government research funding. PAT has received research grants from Sanofi Pasteur, GSK, Novartis and Janssen, and payment for lectures from 3M and meeting expenses from Biomerrieux. SCC has received research grants from Pfizer and GSK. BHT has received research funding from Pfizer (IIR portal). All grants and honoraria are paid into accounts within the respective institutions. This does not alter our adherence to PLOS ONE policies on sharing data and materials. All other authors have nothing to declare. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest.

Streptococcus pneumoniae infections arising in hospitalized patients are often assumed to be sporadic and linked to community acquisition. Here, whole-genome sequencing was used to demonstrate nosocomial acquisition of antimicrobial-resistant sequence type 156 (ST156) serotype 9V S. pneumoniae in 3 respiratory patients that resulted in two bacteremias and one lower respiratory tract infection. Two of the cases arose in patients who had recently been discharged from the hospital and were readmitted from the community. Nosocomial spread was suspected solely because of the highly unusual resistance pattern and case presentations within 24 h of one another. The outbreak highlights the potential for rapid transmission and the short incubation period in the respiratory ward setting., (Copyright © 2017 Jauneikaite et al.)

Streptococcus pneumoniae is a major respiratory tract pathogen causing pneumococcal disease mainly in children aged less than five years and in the elderly. Ninety-eight different capsular types (serotypes) of pneumococci have been reported, but pneumococcal conjugate vaccines (PCV) include polysaccharide antigens against only 7, 10 or 13 serotypes. It is therefore important to track the emergence of serotypes due to the clonal expansion of non-vaccine serotypes. Increased numbers of carried and disease-causing pneumococci are now being analysed as part of the post-PCV implementation surveillance studies and hence rapid, accurate and cost-effective typing methods are important. Here we describe serotyping methods published prior to 10th November 2014 for pneumococcal capsule typing. Sixteen methods were identified; six were based on serological tests using immunological properties of the capsular epitopes, eight were semi-automated molecular tests, and one describes the identification of capsular type directly from whole genome data, which also allows for further intra and inter-genome analyses. There was no single method that could be recommended for all pneumococcal capsular typing applications. Although the Quellung reaction is still considered to be the gold-standard, laboratories should take into account the number of pneumococcal isolates and the type of samples to be used for testing, the time frame for the results and the resources available in order to select the most appropriate method. Most likely, a combination of phenotypic and genotypic methods would be optimal to monitor and evaluate the impact of pneumococcal conjugate vaccines and to provide information for future vaccine formulations., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: Streptococcus pneumoniae is a major cause of bacterial infections resulting in significant morbidity and mortality worldwide. Currently, up to 13 serotypes are included in pneumococcal conjugate vaccines (PCVs). However, the serotype formulation of these vaccines was initially designed to protect children against serotypes most commonly causing invasive disease in North America, and may not reflect the serotype distribution across the world. Data regarding pneumococcal epidemiology from the other parts of the world, in particular South East Asia, has not been reviewed., Methods: This systematic literature review analyses published serotype data regarding S. pneumoniae isolates from South East Asian countries (defined as countries belonging to the Association of South East Asian Nations, ASEAN): Brunei, Cambodia, Indonesia, Laos, Malaysia, Myanmar, Philippines, Singapore, Thailand and Vietnam up to 3rd of March 2012., Results: Analysis of data from six ASEAN countries, from which information on pneumococcal serotypes was available, showed that the most common disease causing serotypes (in rank order) were 19F, 23F, 14, 6B, 1, 19A and 3. Serotype distribution of pneumococcal isolates was similar across the ASEAN region. Serotype level data was more commonly reported for pneumococcal isolates causing invasive pneumococcal disease than for those from non-invasive disease. Studies from Malaysia, Thailand and Singapore contributed the largest proportion of pneumococcal isolates, and serotype data, when compared to other ASEAN countries., Conclusion: This review demonstrates that the majority of IPD causing serotypes in SE Asia are included in currently licensed PCVs. However, PCV's are included in the routine childhood immunisation schedule of only one of the ten countries included in this analysis. Our findings demonstrate the scarcity of information available on serotype prevalence and distribution of pneumococci in SE Asia., (Copyright © 2012 Elsevier Ltd. All rights reserved.)