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Background: Streptococcus pneumoniae (pneumococcus) is a human nasopharyngeal tract coloniser responsible for invasive pneumococcal disease, which is largely vaccine preventable. Vaccination is recommended from birth for all, and through adulthood for those with risk conditions., Aims: To describe the clinical and serotype analysis of pneumococcus bacteraemia over a 10-year period., Methods: A 10-year (February 2011-December 2020) retrospective review was performed on all adult (age ≥18 years) pneumococcus bacteraemia presenting to the four public hospitals in Western Sydney, Australia. Comorbidities and risk factors were recorded., Results: Three hundred unique episodes of S. pneumoniae bloodstream infection (SPBI) were identified during the study period. The median age for SPBI was 63 years with 31.7% aged 70 years or older. A 94.7% had one or more risks factors for SPBI. Pneumonia was reported in 80% of all SPBI, whereas meningitis was reported in 6% and infective endocarditis in <1%. Asplenia was noted in 2.4%. Seven- and 30-day mortality was 6.6% and 11.9%, with a higher 30-day mortality in those aged ≥70 years (24.4%). The serotype distribution showed 7-valent conjugate vaccine covered 11.0% of all isolates, whereas 13-valent conjugate vaccine (13vPCV) and a 23-valent polysaccharide vaccine (23vPPV) covered 41.7% and 69.0% respectively. Immunisation details were available for 110 individuals, of whom, only 7.3% had received pneumococcal vaccination., Conclusions: Most patients with pneumococcal bacteraemia had age- or comorbidity-related risk factors but were not vaccinated. Two-thirds of cases occurred in people aged <70 years. 13vPCV and 23vPPV covered 41.7% and 69.0% of bacteraemic isolates., (© 2023 The Authors. Internal Medicine Journal published by John Wiley & Sons Australia, Ltd on behalf of Royal Australasian College of Physicians.)

Background: The Invasive Respiratory Infection Surveillance (IRIS) Consortium was established to assess the impact of the COVID-19 pandemic on invasive diseases caused by Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis, and Streptococcus agalactiae. We aimed to analyse the incidence and distribution of these diseases during the first 2 years of the COVID-19 pandemic compared to the 2 years preceding the pandemic., Methods: For this prospective analysis, laboratories in 30 countries and territories representing five continents submitted surveillance data from Jan 1, 2018, to Jan 2, 2022, to private projects within databases in PubMLST. The impact of COVID-19 containment measures on the overall number of cases was analysed, and changes in disease distributions by patient age and serotype or group were examined. Interrupted time-series analyses were done to quantify the impact of pandemic response measures and their relaxation on disease rates, and autoregressive integrated moving average models were used to estimate effect sizes and forecast counterfactual trends by hemisphere., Findings: Overall, 116 841 cases were analysed: 76 481 in 2018-19, before the pandemic, and 40 360 in 2020-21, during the pandemic. During the pandemic there was a significant reduction in the risk of disease caused by S pneumoniae (risk ratio 0·47; 95% CI 0·40-0·55), H influenzae (0·51; 0·40-0·66) and N meningitidis (0·26; 0·21-0·31), while no significant changes were observed for S agalactiae (1·02; 0·75-1·40), which is not transmitted via the respiratory route. No major changes in the distribution of cases were observed when stratified by patient age or serotype or group. An estimated 36 289 (95% prediction interval 17 145-55 434) cases of invasive bacterial disease were averted during the first 2 years of the pandemic among IRIS-participating countries and territories., Interpretation: COVID-19 containment measures were associated with a sustained decrease in the incidence of invasive disease caused by S pneumoniae, H influenzae, and N meningitidis during the first 2 years of the pandemic, but cases began to increase in some countries towards the end of 2021 as pandemic restrictions were lifted. These IRIS data provide a better understanding of microbial transmission, will inform vaccine development and implementation, and can contribute to health-care service planning and provision of policies., Funding: Wellcome Trust, NIHR Oxford Biomedical Research Centre, Spanish Ministry of Science and Innovation, Korea Disease Control and Prevention Agency, Torsten Söderberg Foundation, Stockholm County Council, Swedish Research Council, German Federal Ministry of Health, Robert Koch Institute, Pfizer, Merck, and the Greek National Public Health Organization., Competing Interests: Declaration of interests The UK Health Security Agency's Immunisation and Vaccine Preventable Diseases Division has provided vaccine manufacturers (GSK, Pfizer, and Sanofi) with post-marketing surveillance reports, which the Marketing Authorization Holders are required to submit to the UK Licensing authority in compliance with their Risk Management Strategy. A cost recovery charge is made for these reports. The UK Health Security Agency's Respiratory and Vaccine Preventable Bacteria Reference Unit has received unrestricted research grants from Pfizer to participate in pneumococcal surveillance projects. CHI de Créteil (France) received research grants from the French Public Health Agency, Pfizer, and MSD. University Hospitals Leuven (Belgium) received research grants from Merck-MSD and Pfizer, and consulting fees from Merck-MSD. SD received personal payments or honoraria from Pfizer. The Swiss National Reference Center for Invasive Pneumococci received funding from the Federal Office of Public Health. MH has received grants from Pfizer and personal fees (for being on an advisory board) from Pfizer and Merck Sharp & Dohme. The National Medicines Institute (Warsaw, Poland) received funding from the Polish Ministry of Health, the Polish Ministry of Science and Higher Education, Pfizer, and MSD. AS received payments from MSD and Pfizer for lectures, and from MSD, Pfizer, and Sanofi Pasteur for participation in advisory boards. AS is the unpaid Vice President of the European Meningococcal and Haemophilus Disease Society. The Finnish Institute for Health and Welfare (Finland) received research funding from Pfizer. ABB is an unpaid adviser to WHO, providing expertise related to vaccines and antimicrobial resistance. ABB is an unpaid General Assembly member (2022 onwards), and has been a board member (2016–22) and Secretary (2018–22), of the International Society of Pneumonia and Pneumococcal Diseases (ISPPD). MD has received financial support from Pfizer to attend national scientific meetings. MdP received grant funding from the National Research Foundation (South Africa) and the Bill & Melinda Gates Foundation to support the International Pathogenic Neisseria Conference (IPNC) 2022 meeting. MdP received personal support from the ISPPD to participate in the ISPPD conference in 2022, and was a member of the organising and scientific committee for the IPNC meeting in 2022. HH and MC received a grant from Pfizer (W1243730) to investigate Irish pneumococcal serotypes by whole-genome sequencing. HH received payment from Scottish Hospitals Enquiry for expert testimony. HH was the President of the Healthcare Infection Society (2018–22). KAJ received personal royalties from GlaxoSmithKline, and personal honoraria from the Wellcome Trust. SL performs contract research on behalf of St George's University of London for pharmaceutical companies (GlaxoSmithKline, Pfizer, and Sanofi), including vaccine manufacturers, but does not receive any personal remuneration. T-TL received consulting fees from the Trond Mohn Foundation. T-TL is an unpaid board member of the European Meningococcal and Haemophilus Disease Society and the German Society for Hygiene and Microbiology, committee for microbial systematics, population genetics and infection epidemiology. SM participated on an unpaid advisory board for Pfizer for the meningococcal type B vaccine in South Africa in 2020. WM received funding from GlaxoSmithKline and Pfizer for investigator-initiated research on meningitis B (MenB) strain vaccine coverage. CS received financial support for flights, accommodation, and registration to attend the 2022 ISPPD meeting in Canada. H-CS received funding from Pfizer for a pneumococcal carriage project. H-CS received funding for participation on a data safety monitoring board or advisory board for MSD. LS received personal support from the European Centre for Disease Prevention and Control for attending the European Scientific Conference on Applied Infectious Disease Epidemiology in 2022. MPGvdL received consulting fees from Pfizer, Merck, and GlaxoSmithKline; payment or honoraria from Pfizer and Merck; and support for attending meetings or travel, or both, from Pfizer. AvG is the chairperson for the National Advisory Group on Immunization of South Africa. NMvS received fees for services and consulting fees from MSD and GlaxoSmithKline, and research funding from the Dutch Health Counsel, US National Institutes of Health, and Amsterdam University Medical Centers, and from MSD and GlaxoSmithKline, which are all directly paid to the institution. NMvS holds a patent (WO 2013/020090 A3) on vaccine development against Streptococcus pyogenes. NMvS is an unpaid scientific adviser to the ItsME foundation, and a scientific adviser to the StrepAotearoa New Zealand project but fees are paid to the University of Amsterdam. NMvS holds personal stocks in Genmab. JY received payments for lectures given at scientific meetings organised by MSD and Pfizer; received support from MSD and Pfizer to attend national and international scientific meetings; and participated in advisory boards for MSD and Pfizer. DS is supported by an Oxford Clarendon Scholarship. All other authors declare no competing interests., (Copyright © 2023 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)

Background: We aimed to assess the direct protective effect of 13 valent pneumococcal conjugate vaccine (13vPCV) against invasive pneumococcal pneumonia (IPP; including pneumonia and empyema) in children using a nation-wide case-control study across 11 paediatric tertiary hospitals in Australia., Methods: Children < 18 years old admitted with pneumonia were eligible for enrolment. IPP was defined as Streptococcus pneumoniae (SP) cultured or detected by polymerase chain reaction (PCR) from blood or pleural fluid. Causative SP serotype (ST) was determined from blood or pleural fluid SP isolates by molecular methods in PCR positive specimens or else inferred from nasopharyngeal isolates. For each IPP case, 20 population controls matched by age and socio-economic status were sampled from the Australian Immunisation Register. Conditional logistic regression was used to estimate the adjusted odds ratio (aOR) of being fully vaccinated with 13vPCV (≥3 doses versus < 3 doses) among IPP cases compared to controls, adjusted for sex and Indigenous status., Results: From February 2015 to September 2018, we enrolled 1,168 children with pneumonia; 779 were 13vPCV-eligible and were individually matched to 15,580 controls. SP was confirmed in 195 IPP cases, 181 of whom had empyema. ST3 and ST19A were identified in 52% (102/195) and 11% (21/195) of IPP cases respectively. The aOR of being fully vaccinated with 13vPCV was 0.8 (95% CI 0.6-1.0) among IPP cases compared to matched controls., Conclusion: We failed to identify a strong direct protective effect of 13vPCV against IPP among Australian children, where disease was largely driven by ST3., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

(1) Background: How to optimally promote the process of acquiring and learning a new motor skill is still one of the fundamental questions often raised in training and movement science, rehabilitation, and physical education. This study is aimed at investigating the effects of differential learning (DL) and the elements of OPTIMAL theory on learning a goal-kicking skill in futsal, especially under the conditions of external and internal foci. (2) Methods: A total of 40 female beginners were randomly assigned to, and equally distributed among, five different interventions. Within a pretest and post-test design, with retention and transfer tests, participants practiced for 12 weeks, involving two 20-min sessions per week. The tests involved a kicking skill test. Data were analyzed with a one-way ANOVA. (3) Results: Statistically significant differences with large effect sizes were found between differential learning (DL) with an external focus, DL with an internal focus, DL with no focus, traditional training with an external focus, and traditional training with control groups in the post-, retention, and transfer tests. (4) Conclusions: The results indicate the clear advantages of DL. It is well worth putting further efforts into investigating a more differentiated application of instructions combined with exercises for DL.

In every year, up to one million children die due to pneumococcal disease. Children infected with Human Immunodeficiency Virus (HIV) are mostly affected, as they appear to have higher rates of pneumococcal carriage and invasive disease. Successful immunity is dependent on mounting a sufficient immune response to the vaccine. We conducted a double blinded crossover randomised controlled trial to determine the serum antibody response (≥4-fold and geometric mean concentration) to pneumococcal vaccine (PCV13) serotypes at 3 months after second vaccination. We also determined the number and proportion of children carrying new (not present at baseline) vaccine serotypes of S. pneumoniae isolated from nasopharynx at 6 months post initial vaccination in recipients of Prevenar13 ® compared with those given Haemophilus influenzae -type b (Hib) vaccine (control). The study was conducted at St Augustine's also known as Teule Hospital in Muheza, Tanga Tanzania. 225 HIV infected children aged 1-14 years were enrolled from Jan 2013 to Nov 2013 and randomised to Prevenar13 ® or Hib vaccines each given at baseline and 2-3 months later. Nasopharyngeal and serum samples were collected at baseline and 4-6 months later. Serotyping was done by Quellung Reaction using Staten antisera. Serum antibodies were ELISA quantified. The study revealed a non-significant reduction in the acquisition of new vaccine serotypes of S. pneumoniae in the recipients of PCV13 by nearly a third compared to those who received Hib vaccine. The vaccine efficacy was 30.5% (95% confidence interval [CI] -6.4-54.6%, P = 0.100)]. The antibody response was not enough to induce a 4-fold rise in GMC in 7 of the 13 vaccine serotypes. When combining the effects of preventing new acquisition and clearing existing vaccine type carriage, the overall efficacy was 31.5% (95% CI 1.5-52.4%, P = 0.045). In the PCV13 group, the proportion of participants carrying vaccine serotype was significantly lower after 2 doses of PCV13 (30%; 32/107), compared with the baseline proportion (48%; 51/107). The introduction of PCV13 targeting HIV-positive children in a setting similar to Tanzania is likely to be associated with appreciable decrease in the acquisition and carriage of pneumococci, which is an important marker of the likely effect of the vaccine on pneumococcal disease., Clinical Trial Registration: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=335579, identifier ACTRN12610000999033., Competing Interests: The study was funded by Pfizer, a company that also supplied the PCV13 vaccine. However, the company did not have any contribution on the analysis or interpretation of the study results. RB received funding for an investigator-initiated study. JKY is currently a full time employee of Sanofi Pasteur; his contribution to this work was made before he joined the company. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Makenga, Mtove, Yin, Mziray, Bwana, Kisinza, Mjema, Amos, Antony, Shingadia, Oftadeh and Booy.)

Background: Empyema is a serious complication of pneumonia frequently caused by Streptococcus pneumoniae (SP). We assessed the impact of the 13-valent pneumococcal conjugate vaccine (13vPCV) on childhood pneumonia and empyema after inclusion in the Australian National Immunisation Program., Methods: For bacterial pneumonia and empyema hospitalisations, we ascertained incidence rates (IRs) using the National Hospital Morbidity Database International Statistical Classification of Disease discharge codes and relevant population denominators, and calculated incidence rate ratios (IRR) comparing the 13vPCV period (June 2012-May 2017) with the 7vPCV period (June 2007-May 2011). Blood and pleural fluid (PF) cultures and PF PCR of 401 children with empyema from 11 Australian hospitals during the 13vPCV period were compared with our previous study in the 7vPCV period., Findings: Across 7vPCV and 13vPCV periods, IRs per million children (95% CIs) were 1605 (1588 to 1621) and 1272 (1259 to 1285) for bacterial pneumonia, and 14.23 (12.67 to 15.79) and 17.89 (16.37 to 19.42) for empyema hospitalisations. IRRs were 0.79 (0.78 to 0.80) for bacterial pneumonia and 1.25 (1.09 to 1.44) for empyema. Of 161 empyema cases with SP serotypes, 147 (91.3%) were vaccine types. ST3 accounted for 76.4% of identified serotypes in the 13vPCV period, more than double than the 7vPCV period (p<0.001); ST19A decreased from 36.4% to 12.4%. No cases of ST1 empyema were identified in the 13vPCV period versus 14.5% in the 7vPCV period., Interpretation: 13vPCV resulted in a significant reduction in all-cause hospitalisations for bacterial pneumonia but empyema hospitalisations significantly increased, with emergence of pneumococcal ST3 as the dominant serotype in empyema., Trial Registration Number: Australian and New Zealand Clinical Trial Registry ACTRN 12614000354684., Competing Interests: Competing interests: HM is an investigator on sponsored vaccine trials. Her institution receives funding from Pfizer and GSK for investigator-led research. She does not receive any personal payments from Industry., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

The decline in invasive pneumococcal disease (IPD), following the introduction of the 7-valent pneumococcal conjugate vaccination (PCV-7), was tempered by emergence of non-vaccine serotypes, particularly 19A. In Australia, three years after PCV-7 was replaced by PCV-13, containing 19A and 19F antigens, serogroup 19 was still a prominent cause of IPD in children under five. In this study we examined the evolution of serogroup 19 before and after introduction of paediatric vaccines in New South Wales (NSW), Australia. Genomes of 124 serogroup 19 IPD isolates collected before (2004) and after introduction of PCV-7 (2008) and PCV-13 (2014), from children under five in NSW, were analysed. Eleven core genome sequence clusters (cgSC) and 35 multilocus sequence types (ST) were identified. The majority (78/124) of the isolates belonged to four cgSCs: cgSC7 (ST199), cgSC11 (ST320), cgSC8 (ST63) and cgSC9 (ST2345). ST63 and ST2345 were exclusively serotype 19A and accounted for its predominantly intermediate penicillin resistance; these two clusters first appeared in 2008 and largely disappeared after introduction of PCV-13. Serogroup 19 was responsible for the highest proportion of vaccine failures in NSW. Relatively low immunogenicity of serogroup 19 antigens and Australia's three-dose vaccine schedule could affect the population dynamics of this serogroup.

Background: China is one of ten countries with the highest prevalence rate of pneumococcal infections. However, there is limited serotype surveillance data for Streptococcus pneumoniae, especially from the community or rural regions, partly due to limited serotyping capacity because Quellung serotyping is only available in few centers in China. The aim of this study was to develop a simple, practical and economic pneumococcal serotype prediction strategy suitable for future serotype surveillance in China., Methods: In this study, 193 S. pneumoniae isolates were collected from hospitalized children, 96.9 % of whom were < 5 years old. The cpsB sequetyping, complemented by selective and modified USA CDC sequential multiplex-PCR, was performed on all the isolates, and serotypes 6A-6D specific PCRs were done on all serogroup 6 isolates. Based on systematic analysis of available GenBank cpsB sequences, we established a more comprehensive cpsB sequence database than originally published for cpsB sequetyping. Antibiotic susceptibility of all isolates was determined using the disk diffusion or E-test assays., Results: We built up a comprehensive S. pneumoniae serotype cpsB sequetyping database for all the 95 described serotypes first, and then developed a simple strategy for serotype prediction based on the improved cpsB sequetyping and selective multiplex-PCR. Using the developed serotype prediction strategy, 191 of 193 isolates were successfully "serotyped", and only two isolates were "non-serotypeable". Sixteen serotypes were identified among the 191 "serotypeable" isolates. The serotype distribution of the isolates from high to low was: 19 F (34.7 %), 23 F (17.1 %), 19A (11.9 %), 14 (7.3 %), 15B/15C (6.7 %), 6B (6.7 %), 6A (6.2 %), 9 V/9A (1.6 %); serotypes 6C, 3, 15 F/15A, 23A and 20 (each 1.1 %); serotypes 10B, 28 F/28A and 34 (each 0.5 %). The prevalence of parenteral penicillin resistance was 1.0 % in the non-meningitis isolates and 88.6 % in meningitis isolates. The total rate of multidrug resistance was 86.8 %., Conclusions: The integrated cpsB sequetyping supplemented with selective mPCR and serotypes 6A-6D specific PCRs "cocktail" strategy is practical, simple and cost-effective for use in pneumococcal infection serotype surveillance in China. For hospitalized children with non-meningitis penicillin-susceptible pneumococcal infections, clinicians still can use narrow-spectrum and cheaper penicillin, using the parenteral route, rather than using broader-spectrum and more expensive antimicrobials.

Background: Pneumococcal colonization of the nasopharynx is especially common in young children and is a pre-requisite for pneumococcal disease. Those with immunosuppression, such as HIV, are at higher risk of colonization and disease, especially at older ages. Currently, vaccination schedules are only offered to children under 6 months of age, despite the large impact of pneumococcal disease in older unvaccinated children with HIV. We conducted a study to assess the prevalence of, and risk factors for, pneumococcal carriage in HIV-positive children aged <15 years., Methods: We collected a single nasopharyngeal swab from 142 HIV-infected children aged 1-14 years over a 2-month period. To detect carriage of pneumococcus, these samples were cultured and serotyped; PCR was performed on negative samples. We also collected epidemiological data via survey and medical records., Results: The overall carriage rate was 81% and was at least 76% in those aged 5-14 years. The 7-, 10-, and 13-valent pneumococcal vaccines would cover 37%, 37%, and 49% of children with carriage, respectively. In the multivariate analysis, we identified increase in weight since last visit (p=0.028) and the existence of care-givers who had respiratory symptoms in the past week (p=0.022) as risk factors for carriage. Weight gain was also significantly associated with antiretroviral use (p=0.002)., Conclusions: These data illuminate the little known area of pneumococcal carriage in older HIV-infected children as well as finding novel risk factors for pneumococcal carriage, namely the association with household members who have respiratory symptoms and with an increase in the child's weight prior to swabbing. Weight gain may be due to an increase in health enabling more mobility and increasing the risk of acquiring carriage. The carriage rate observed (81%) is one of the highest recorded. Further research should address whether vaccination can prevent the acquisition of carriage and so protect against disease., (Copyright © 2012 International Society for Infectious Diseases. All rights reserved.)

Multilocus sequence typing (MLST) was applied to all unique serotype 6C and 6D isolates and a random selection of serotype 6B and 6A isolates from nasopharyngeal swabs from Fijian children enrolled in a recent vaccine trial. The results suggest that Fijian serotype 6D has arisen independently from both serotypes 6A/C and 6B.

We tested 121 pneumococcal serogroup 6 isolates (including 30 serotype 6C and 24 serotype 6D isolates) by serotype-specific PCR and the Quellung reaction, using "old" and "new" pool B, factor 6b, and new factor 6d antisera. In combination with group B and other factor antisera, factor 6d antiserum can reliably identify the newly described serotype 6D.

Macrolide resistance in Streptococcus pneumoniae has emerged as an important clinical problem worldwide over the past decade. The aim of this study was to analyze the phenotypes (serotype and antibiotic susceptibility), genotypes (multilocus sequence type [MLST] and antibiotic resistance gene/transposon profiles) among the 31% (102/328) of invasive isolates from children in New South Wales, Australia, in 2005 that were resistant to erythromycin. Three serotypes--19F (47 isolates [46%]), 14 (27 isolates [26%]), and 6B (12 isolates [12%])--accounted for 86 (84%) of these 102 isolates. Seventy four (73%) isolates had the macrolide-lincosamide-streptogramin B (MLS(B)) resistance phenotype and carried Tn916 transposons (most commonly Tn6002); of these, 73 (99%) contained the erythromycin ribosomal methylase gene [erm(B)], 34 (47%) also carried the macrolide efflux gene [mef(E)], and 41 (55%) belonged to serotype 19F. Of 28 (27%) isolates with the M phenotype, 22 (79%) carried mef(A), including 16 (57%) belonging to serotype 14, and only six (19%) carried Tn916 transposons. Most (84%) isolates which contained mef also contained one of the msr(A) homologues, mel or msr(D); 38 of 40 (95%) isolates with mef(E) (on mega) carried mel, and of 28 (39%) isolates with mef(A), 10 (39%) carried mel and another 11(39%) carried msr(D), on Tn1207.1. Two predominant macrolide-resistant S. pneumoniae clonal clusters (CCs) were identified in this population. CC-271 contained 44% of isolates, most of which belonged to serotype 19F, had the MLS(B) phenotype, were multidrug resistant, and carried transposons of the Tn916 family; CC-15 contained 23% of isolates, most of which were serotype 14, had the M phenotype, and carried mef(A) on Tn1207.1. Erythromycin resistance among S. pneumoniae isolates in New South Wales is mainly due to the dissemination of multidrug-resistant S. pneumoniae strains or horizontal spread of the Tn916 family of transposons.

Background: A putative Streptococcus pneumoniae serotype, 6D, resulting from the introduction of wciN(beta) into serotype 6B has been proposed., Methods: We studied 98 unique serogroup 6 isolates from Fijian children, two-thirds of whom had received at least 1 dose of 7-valent pneumococcal conjugate vaccine, and 51 invasive isolates from Australian children. We used a polymerase chain reaction (PCR) system that targets both wciN(beta) and the single-nucleotide polymorphism that differentiates serotypes 6A and 6B-wciP584g (6A) and wciP584a (6B)., Results: Two (9%) of 22 Australian isolates and 24 (38%) of 64 Fijian isolates previously identified as 6A by the Quellung reaction and wciP584g PCR contained wciN(beta) and were designated as 6C; 14 (41%) of 34 Fijian isolates previously identified as 6B by the Quellung reaction and wciP584a PCR contained wciN(beta) and were designated as the new putative serotype 6D. A significantly smaller proportion of children from whom serotype 6D was isolated (2/14 [14%]) had not received PCV-7, compared with the proportion of those from whom serotype 6B was isolated (11/20 [55%]) (P < .05)., Conclusion: This is the first report of naturally occurring S. pneumoniae serotype 6D.

In this study, we developed a simple, reliable, serotype-specific PCR method to differentiate Streptococcus pneumoniae serotypes 6A, 6B, and 6C. It was more efficient and practical than the assays currently being used to identify serotypes 6A, 6B, and 6C. Of 120 selected serogroup 6 isolates from subjects with invasive (n = 101) and noninvasive (n = 19) pneumococcal disease, most of which were collected after 2003 in New South Wales, 45 had been identified as 6A and 75 had been identified as 6B by the Quellung reaction. PCR analysis confirmed the results for serotype 6B isolates and identified two different subtypes. Fourteen of 45 isolates that had been identified as serotype 6A actually belonged to serotype 6C.