Global Pneumococcal Disease and Policies for Control

Abstract

Oral Poster AbstractsISPPD-0508 Global Pneumococcal Disease and Policies for Control: GLOBAL SEROTYPE DISTRIBUTION OF INVASIVE PNEUMOCOCCAL DISEASE (IPD) IN OLDER CHILDREN AND ADULTS: THE AGEDD STUDYM. Deloria Knoll1, B.A. Nonyane2, C. Garcia1, O.S. Levine3, K.L. O’Brien1, H.L. Johnson41International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore MD, USA; 2International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore MD, USA; 3Global Development Program, Bill & Melinda Gates Foundation (formerly of JHSPH), Seattle WA, USA; 4Monitoring & Evaluation Policy & Performance, GAVI Alliance (formerly of JHSPH), Geneva, SwitzerlandBackground and Aims: Global serotype distribution of IPD in children ≥5 years old and adults pre-pneumococcal conjugate vaccine (PCV) introduction has not been described. We aimed to estimate the proportion due to top serotypes by geographic region.Methods: A systematic literature review identified studies reporting ≥20 IPD cases with serotype/serogroup information. We estimated the proportion of IPD due to 20 serotypes: PCV13-type, 22F, 32F, and any others in the top 13 of each geographic region (8, 9N, 10A, 12F, 16F, 20D). All other serotypes were grouped. Random-effects meta-analysis was used to estimate the average serotype proportion, normalizing to 100 percent.Results: Analyses included 72,954 isolates (>3500 in each region) from children ≥5 years and adults from 77 studies in 53 countries. 70% of disease was accounted for by 9 serotypes in Africa, 12 in North America, 12 in Europe, 13 in Oceania, 14 in Latin America and Caribbean and 16 in Asia. Serotype 1 or 14 was the most common in all regions. Six serotypes (3, 6B, 7F, 14, 19F, 23F) were among the top 13 in all regions. Eleven serotypes (1, 3, 4, 5, 6B, 8, 9V, 14, 19A, 19F, 23F) covered the top 5 in all regions. Vaccine serotypes accounted for >50% of IPD: regional PCV10 plus 6A coverage range=52–62%, PCV13=60–75%, PCV15=64–77%, and 19/23 serotypes in polysaccharide vaccine (PPV23)=72–87%.Conclusion: A limited set of serotypes are common in older children and adults in all regions. Serotypes in existing vaccines included >50% of IPD. PCV13 and PPV23 add approximately 10% and 24%, respectively.No conflict of interestISPPD-0273 Global Pneumococcal Disease and Policies for Control: MENINGOENCEPHALITIS: STREPTOCOCCUS PNEUMONIAE IS AMONG THE MAJOR CAUSES IN ADULTS IN RURAL KENYAA. Amulele1, C. Harris1, M. Ooko1, A. Mwanzu1, R. Njeru1, A. Etyang1, J.A.G. Scott1, J.A.G. Scott2, S.C. Morpeth1, S.C. Morpeth31Epidemiology and Demographic, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya; 2Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom; 3Nuffield Department of Clinical Medicine John Radcliffe Hospital, University of Oxford, London, United KingdomBackground and Aims: We aimed to identify the aetiology of meningoencephalitis in adult patients at Kilifi District Hospital (KDH) and to describe their clinical presentations and outcomes.Methods: Adult patients admitted to KDH, January 2007–October 2012, with any two of: temperature >37.5°C, meningism, altered mental status; were suspected meningoencephalitis cases, eligible for a lumbar puncture (LP). Patients with cerebrospinal fluid (CSF) collected and stored during this period were included. Real-time multiplex PCR (Fast-Track Diagnostics, Luxembourg) targeting 21 pathogens and a cryptococcal antigen lateral-flow assay (Immuno-Mycologics, USA) were performed retrospectively and analyzed with microscopy, culture, antigen tests and clinical data from admission.Results: Adults admitted to the wards were 18,527; 665 (3.6%) met the LP criteria, performed in 554 (83%) patients. CSF samples for 357 (64%) clinical episodes were sufficient for storage. Of 268 (75%) episodes tested, 11 from 2007 and 257 from 2010 to 2012, 161 (60%) were abnormal and consistent with suspected meningoencephalitis. A pathogen was identified in 50 (31%) abnormal episodes; 22/159 (14%) with Cryptococcus neoformans, 11/160 (7%) with Streptococcus pneumoniae. HIV prevalence recorded in cryptococcal or pneumococcal meningitis patients was 20/21 (95%) and 5/10 (50%) respectively and overall at 71% (104/147). Death in hospital occurred in 76/159 (48%) episodes, 7 (64%) with pneumococcal meningitis, 10 (45%) with cryptococcal meningitis.Conclusion: S. pneumoniae is a major cause of morbidity and mortality in adult meningoencephalitis in Kenya, after C. neoformans. Pneumococcal conjugate vaccine was introduced in Kenya in 2011 and CSF PCR may enhance the evaluation of impact.No conflict of interestISPPD-0505 Global Pneumococcal Disease and Policies for Control: IMPACT OF THIRTEEN-VALENT PNEUMOCOCCAL CONJUGATE VACCINE ON PNEUMOCOCCAL CARRIAGE IN DIFFERENT COUNTRIES — MATHEMATICAL MODELLING STUDYY. H. Choi1, A. Melegaro2, A. Hoek3, G. Mackenzie4, N. Gay51Immunisation Hepatitis and Blood Safety Department, Public Health England — Colindale, London, United Kingdom; 2DONDENA Centre for Research on Social Dynamics, Bocconi University, Milan, Italy; 3Immunisation Hepatitis and Blood Safety Department, Public Health England, London, United Kingdom; 4Medical Research Council (UK), Medical Research Council (UK), Fajara and Basse stations, Gambia; 5Hungerford, Fu Consulting, Berkshire, United KingdomBackground and Aims: Many developed countries have introduced various pneumococcal conjugate vaccines (PCV) and almost eliminated PCV serotypes from their populations. Many other countries, inspired by this impact, are now considering introduction of PCV into their National Immunisation Programmes. As the carriage prevalence and serotype distributions can vary widely between countries, a different impact of the PCV programme is possible. PCV13’s protection against development of invasive disease is high, but protection against carriage is weaker; the degree of protection against acquisition of carriage is little more than 50%, and the duration of this protection is thought to be short. This raises the question of whether such a vaccine will be able to eliminate PCV subtypes from high prevalence populations. This question is addressed using mathematical models.Materials and Methods: A simple age-structured compartmental model was developed to describe the transmission dynamics of pneumococci in the Gambia, and in England & Wales (E&W). Local pre-PCV carriage data were used to estimate transmission parameters in the model. A simulation model assessed the long-term impact of the PCV13 programmes in these two countries.Results: Simulation results suggest that all E&W vaccination scenarios have the potential to eliminate PCV13 serotypes from circulation. Conversely, model simulations for the Gambia scenarios produced a reduction in the level of PCV13 serotype carriage prevalence but failed to eliminate PCV13 serotypes.Conclusion: In developed countries, where carriage is concentrated among young children, PCV13, despite its limited protection against carriage, can eliminate PCV13 serotypes from the population. However, in developing countries with a high carriage prevalence among adults, PCV13 may not be able to eliminate PCV13 serotypes.No conflict of interestISPPD-0245 Global Pneumococcal Disease and Policies for Control: UNDERSTANDING THE IMPACT OF PNEUMOCOCCAL CONJUGATE VACCINE IN INDIA: A SYSTEMATIC COMPARISON OF IMPACT ESTIMATES FOR PCV, HIB AND ROTAVIRUS VACCINESK. Hayford1, B. Wahl2, R. Kumar3, N. Thacker4, A. Sutherland2, L. Privor-Dumm2, M. Santosham2, K. O’Brien21Department of Medicine, University Health Network, Toronto, Canada; 2International Health, Johns Hopkins School of Public Health, Baltimore, USA; 3PGIMER School of Public Health, Chandigarh, India; 4Child Health Foundation, Gandhidham, IndiaBackground & Aims: The Indian National Technical Advisory Group on Immunization (NTAGI) recommended pneumococcal conjugate vaccine (PCV) introduction in >1 state in 2008, but the recommendation has not yet been implemented. Some stakeholders argued there were insufficient health and economic impact data to support use of PCV in India. Multiple estimates are now available, creating a challenge for advocacy and communication efforts.Methods: We conducted a review of all published and unpublished national-level modeled estimates of pneumococcus, Haemophilus influenzae type b (Hib), and rotavirus morbidity and mortality, and health and economic impact estimates of these preventive vaccines.Results: Four national pneumococcal mortality estimates are available-two published estimates for year 2000 (all syndromes) and 2010–2011 (pneumococcal pneumonia only) and two unpublished estimates (2005, 2008—all syndrome). 142,361 pneumococcal deaths were estimated in 2000; 136,100 in 2005; and 79,450 in 2008; but models and assumptions are not consistent across estimates. State-level pneumococcal mortality estimates(year 2005) are available but not yet published. National health or economic impact estimates for PCV in India exist but are unpublished. Impact estimates for Hib (n = 1) and rotavirus vaccines (n = 7) are available but assumptions, disease burden and economic inputs are not consistent with PCV impact models.Conclusion: Pneumococcal disease burden estimates in India are available for various years; inferences about changes in disease burden over time are not recommended because modeling strategies are not consistent. Generating robust health and economic impact estimates for PCV -at the state and national level using methods that are comparable to other vaccine impact estimates- will support evidence-based decisions for PCV introduction in India.No conflict of interestISPPD-0486 Global Pneumococcal Disease and Policies for Control: METHODOLOGICAL ISSUES IN THE ANALYSIS OF ‘BEFORE AND AFTER’ VACCINE STUDIESD. Jeffries1, P. Hill2, S. Howie3, E.K. Mulholland4, B. Greenwood5, G. Mackenzie31Statistics, Medical Research Council The Gambia Unit, Fajara, Gambia; 2Centre for International Health, School of Medicine University of Otago Dunedin NZ, Dunedin, New Zealand; 3Child Survival Theme, Medical Research Council The Gambia Unit, Fajara, Gambia; 4Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom; 5Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, United KingdomBackground and Aims: Evaluation of vaccine impact using ‘before and after’ data is complicated by temporal changes in factors which may confound or bias results. We addressed these issues in a study of the impact of pneumococcal conjugate vaccine in The Gambia.Methods: We analysed incidence of primary end-points in pre- and post-intervention periods and performed a cohort analysis. For the pre- and post-analysis, we defined the start of the intervention period as the date when coverage of ≥2 doses across an age range approached its maximum. Individuals may contribute time in both ‘before’ and ‘after’ periods (accounted for by a random effect for subject) to reduce loss of information. We defined potential confounders (e.g. season, malaria) and adjusted for changes in the comparison periods. We identified potential biases, such as changes in case ascertainment or the prevalence of serotypes known to vary markedly over time, and included these variables in stratified and multivariable modelling. End-points unrelated to vaccination (e.g. Gram-negative bacteraemia) were used to indicate potential confounding or bias. We estimated variance using robust methods. Children eligible for vaccination were included in the cohort analysis which may be interpreted as vaccine effectiveness at the individual level. To facilitate control of confounding we used a time-to-event approach specifying vaccination status and age as time-varying covariates. Results are presented in plenary session 6.Conclusion: Analytic techniques are available to improve the evaluation of new vaccines using ‘before and after’ data while taking into account potential confounding and bias.No conflict of interestISPPD-0492 Global Pneumococcal Disease and Policies for Control: INVASIVE SEROTYPES AND PNEUMOCOCCAL MENINGITIS FATALITY IN BURKINA FASO AND TOGO, 2002–2013B.D. Gessner1, S. Yaro2, T.A. Tamekloe3, B. Nacro4, K. Agbenoko5, S. Kroman6, O. Sanou6, J.C. Moisi7, J.E. Mueller8, B.M. Njanpop-Lafourcade81NA, Agence de Medecine Preventive, Paris, France; 2NA, Centre Muraz, Bobo-Dioulasso, Burkina Faso; 3NA, Ministère de la Santé, Lome, Togo 4NA, Centre Hospitalier Universitaire Sourou Sanou, Bobo-Dioulasso, Burkina Faso; 5NA, Centre Hospitalier Regional des Savanes, Dapaong, Togo; 6NA, Agence de Medicine Preventive, Ouagadougou, Burkina Faso; 7NA, Agence de Medicine Preventive, Ferney-Voltaire, France; 8NA, Agence de Medicine Preventive, Paris, FranceBackground and Aims: Many pneumococcal (Sp) meningitis cases in the African meningitis belt result from the invasive serotype 1, which data from other areas indicate should present with relatively low mortality.Methods: We evaluated all age acute bacterial meningitis mortality data from healthcare structure based surveillance systems in northern Togo and western Burkina Faso. All patients had received care based on standard algorithms. Etiologic determination was performed via culture, antigen detection, or polymerase chain reaction (PCR) while serotype/group was determined by PCR or Quellung.Results: Among 4838 patients, the case fatality ratio (CFR) was 34% (275/808) for Sp, and 9% (56/639), 11% (26/229), and 15% (17/111) for serogroups A, W135, and X meningococcus, respectively. Sp CFR varied only modestly by study year (23% [2005] to 46% [2010]) and age group (31% [5–14 years] to 43% [50+ years]) with no particular trend; 56% of Sp deaths occurred from age 5–49 years. Of 355 (43%) evaluated Sp cases, 51% were serotype 1 and 66% were invasive (serotype/groups 1, 4, 5, 7, 14, 18). CFR was 42% for serotype 1 versus other serotypes and for invasive versus non-invasive serotypes. Serotype 1 and invasive serotypes were not associated with lower CFR when stratified by country, age group, or study year. Antibiotic resistance did not predict death.Conclusion: In the African meningitis belt Sp meningitis mortality is higher than other etiologies, affects all age groups, shows no evidence of decreasing, and is not lower for serotype 1 or the broader category of invasive serotypes.Conflict of interestISPPD-0147 Global Pneumococcal Disease and Policies for Control: RELATIVE RATES OF PNEUMOCOCCAL DISEASE ARE DISPROPORTIONATELY HIGH IN ADULTS WITH MULTIPLE CHRONIC MEDICAL CONDITIONSS.I. Pelton1, D. Weycker2, R.A. Farkouh3, K.M. Shea1, J. Edelsberg2, D.R. Strutton31Schools of Medicine and Public Health, Boston University, Boston, USA; 2Outcomes Research, Policy Analysis Inc., Boston, USA; 3Vaccines, Pfizer, Collegeville, USABackground: The high risk of pneumococcal infection among adults with immunocompromising conditions is well recognized; however, the risk among immunocompetent adults with chronic medical conditions, especially those with multiple conditions, is less well established.Methods: A retrospective cohort design using US healthcare claims data (2007–2010) from >35M persons annually was employed. Study population included persons aged ≥18 years, and was stratified by age and risk profile (high-risk [immunocompromised], at-risk [immunocompetent with ≥1 chronic condition], healthy); at-risk individuals were further stratified by number of conditions. At-risk and high-risk conditions, and episodes of pneumococcal disease (PD)—invasive (IPD), pneumococcal pneumonia (PP), all-cause pneumonia (PNE)—were identified via diagnosis, procedure, and drug codes.Results: Persons with ≥2 at-risk conditions accounted for 9–32% of all at-risk adults, depending on age. PD rates increased markedly with number of conditions, and for those with ≥2 conditions, were similar to those in the high-risk group (Table). Among adults 18–34 years, 66–71% of PD occurred in healthy individuals and 4–7% among those with ≥2 at-risk conditions; among adults ≥65 years, corresponding figures were 20–21% and 26–29%. Conclusion: Notwithstanding widespread childhood pneumococcal vaccination and an overall decline in PD among adults, disease risk remains disproportionately high in those with at-risk and high-risk conditions. PD rates are notably high among adults with multiple at-risk conditions; comparable to those among adults with high-risk conditions.Conflict of interestISPPD-0370 Global Pneumococcal Disease and Policies for Control: PNEUMOCOCCAL POLYSACCHARIDE VACCINE AT 9 MONTHS OF AGE IS NOT ASSOCIATED WITH IMPAIRED B-CELL MEMORY OR HYPO-RESPONSIVENESS IN CHILDREN IN PNGP. Richmond1, W.S. Pomat2, A. Fuery1, J.P. Francis2, C. Opa2, P. Siba3, G. Saleu2, D. Anderson4, P. Jacoby4, D. Lehmann4, P. PCV Study Team21Paediatrics and Child health, University of Western Australia, Perth, Australia; 2Infection and Immunity, Papua New Guinea Institute of Medical research, Perth, Australia; 3Director, Papua New Guinea Institute of Medical research, Perth, Australia; 4Telethon Institute for Child health Research, University of Western Australia, Perth, AustraliaIntroduction: 23-valent pneumococcal polysaccharide vaccine (PPV) following pneumococcal conjugate vaccines (PCV) should increase protection however concerns exist regarding hypo-responsiveness and B-cell memory impairment after PPV. We evaluated the persistence of antibody and B-cell memory following PPV at 9 months of age in 3–5 year old children in Papua New Guinea.Methods: 150 children who had received PPV at age 9 mo (after PCV7 at 0–1–2 or 1–2–3 months or no PCV7) and 130 age-matched unvaccinated controls received a 0.1 mL PPV challenge dose at age 3–5 years and blood was collected pre- and 1 month post-challenge. Serotype-specific IgG for serotypes in PCV7 (VT), 2, 5 & 7F was measured by ELISA. B-cell memory for serotypes 1, 2, 7F, 14, 19A, 19F & 23 was measured at age 10 and 18 months (prior-PPV groups) and pre-challenge by polyclonal B-cell stimulation and detection of antibody forming cells on polysaccharide-coated plates by ELISpot.Results: Post-PPV, memory B-cells numbers increased from age 10 months to 3–5 years for 8/9 serotypes (not 23F) and did not differ to PPV naïve controls. Pre-challenge, IgG levels were high, with no significant differences between groups in GMCs or proportions ≥1 µg/mL (range 58–95%). IgG increases after PPV-challenge were modest (1.2 to 2.8-fold) with no significant differences in GMCs, fold-rises or % ≥1 µg/mL between groups. Increased pre-challenge antibody concentrations were associated with a decreased IgG response to challenge.Conclusion: We found no evidence of hypo-responsiveness or impairment of memory B-cells in PNG children at 3–4 years of age after PPV at age 9 months.Conflict of interestISPPD-0496 Global Pneumococcal Disease and Policies for Control: OTITIS MEDIA AND ITS SEQUELAE IN KENYAN SCHOOL CHILDRENE. Simões1, I.M. Macharia2, F. Kiio2, P. Carosone-Link1, S.N. Ndegwa2, J. Ayugi21Dept. of Global Health, University of Colorado at Denver, Denver, USA; 2Dept. of Surgery, University of Nairobi Kenyatta National Hospital, Nairobi, KenyaBackground and Aims: Chronic suppurative otitis media (CSOM), a sequel of acute otitis media (AOM) is a major cause of preventable hearing loss in children in developing countries. In Africa there are few recent studies on the prevalence of AOM and its sequelae. Obtaining representative Kenyan data on the point prevalence of AOM and its sequelae, otitis media with effusion (OME), CSOM and hearing impairment was the goal.Methods: Study subjects were children aged 2 to 15 years enrolled from randomly selected preprimary and primary schools. With parental/guardian consent, subjects had a questionnaire administered, otoscopy and tympanometry done, and audiometry performed on those with ear problems detected on these examinations.Results: Of the 13,109 children examined, 75% were from rural schools. The prevalence’s of CSOM and OME were 15/1000 children and AOM was 7/1000. Apart from retraction of the tympanic membrane (urban 0.3%, rural 0.1%, p < 0.001), there was no statistically significant difference between the prevalence of other middle ear disorders in rural and urban school children. However in rural children, those from the Rift Valley had a significantly higher rate of CSOM 24/1000 than other regions 12/1000; p < 0.0001. The age of onset of ear discharge was before 3.5 years in 50% of children and before 6 years in 75%.Conclusion: Since a significant burden of AOM sequelae occur in Kenyan preschool and school children with the onset mostly, in the first 4 years of life, we question: would pneumococcal vaccines that prevent early recurrent AOM, prevent these nonreversible sequelae?No conflict of interestISPPD-0355 Global Pneumococcal Disease and Policies for Control: EPIDEMIOLOGY OF INVASIVE PNEUMOCOCCAL DISEASE IN HIV EXPOSED-UNINFECTED CHILDREN <1 YEAR OF AGE IN SOUTH AFRICA, 2009 THROUGH 2012C. von Mollendorf1, A. von Gottberg1, S. Meiring2, L. de Gouveia1, V. Quan2, S. Lengana1, K.L. O’ Brien3, K.P. Klugman4, C. Cohen11Centre for Respiratory Diseases and Meningitis, National Institute for Communicable Diseases, Johannesburg, South Africa; 2Division of Public Health Surveillance and Response, National Institute for Communicable Diseases, Johannesburg, South Africa; 3Center for American Indian Health & International Vaccine Access Center, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA; 4Hubert Department of Global Health Rollins School of Public Health and Division of Infectious Diseases, Emory University, Atlanta, USABackground: The prevention of mother-to-child transmission (PMTCT) programme has been rapidly scaled-up in South Africa with a reported decrease in HIV transmission rates from 3.5% (2010) to 2.7% (2011). There are no published data quantifying specific increased risk or mortality of IPD in HIV-exposed uninfected (HEU) children.Methods: We conducted a cohort surveillance study in children <1 year of age with invasive pneumococcal disease (IPD), using data obtained from a national, laboratory-based, surveillance programme. HIV and outcome data were obtained at sentinel sites. Incidences in HIV-infected, HIV-uninfected, HEU and HIV-unexposed uninfected (HUU) children were calculated assuming similar annual HIV prevalence in tested and untested children.Results: We identified 1805 IPD cases in children <1 year of age from 2009 through 2012 from all sites. In children from sentinel sites (n=863), 89% (768/863) had known HIV status. The highest incidence of IPD was in HIV-infected (608/100,000 population) compared with HIV-uninfected children (31/100,000; crude relative risk 19.61 [95% CI 13.67–29.12]). In addition, HEU children had higher incidence of IPD (61/100,000 population) than HUU children (22/100,000; crude relative risk 2.77 [95% CI 1.68–4.74]).Overall case-fatality ratio was high (27%, 234/863), differed between HIV-infected (32%, 75/231) and HIV-uninfected children (24%, 129/537, p=0.008); as well as between HEU (27%, 59/220) and HUU children (21%, 57/266, p=0.08).Discussion: The numbers of HIV-exposed children infected annually continue to drop due to improvements in PMTCT; however we have now shown that these exposed but uninfected children are at increased risk of IPD and mortality compared with HIV-unexposed children.No conflict of interestISPPD-0437 Global Pneumococcal Disease and Policies for Control: SEROTYPE DISTRIBUTION OF STREPTOCOCCUS PNEUMONIAE ASSOCIATED WITH INVASIVE PNEUMOCOCCAL DISEASE IN CHINAM.C. Li1, Z.J. Shao1, Y. Wang2, W.M. Tang3, H.K. Yang41Respiratory infection department, Chinese Center for Disease Control and Prevention(ICDC China CDC), Beijing, China; 2Department of laboratory medicine, Peking Union Medical College Hospital, Beijing, China; 3Medical Affairs, MSD China Holding Co. Ltd, Shanghai, China; 4Global Health Outcomes, Merck, West Point, USABackground and Aims: Invasive pneumococcal disease (IPD) is a serious public health problem in China, yet epidemiology data are limited, especially in adults. The study aimed to examine the serotype distribution of Streptococcus pneumoniae isolated from Chinese patients with IPD.Methods: The multicenter study collected S. pneumoniae positive IPD isolates from normally sterile sites in both pediatric (<18 years) and adult (≥18 years) patients in China between 2009 and 2013. Serotypes were analyzed by Chinese Center for Disease Control and Prevention using Capsule-quellung test.Results: A total of 110 isolates from 60 pediatric and 50 adult IPD cases were collected from 16 hospitals in 13 provinces in China. Overall, the most common serotypes in all ages were 19A, 19F, 23F, 3 and 14. The most frequent serotypes were 19A, 19F, 23F, 1, 5, 14, 6B and 6C in pediatric patients and 3, 19F, 19A, 23F, 14, 20 and 6A in adults. Interestingly, serotype 19A appeared significantly more frequent in infants (<2 years) than other age groups, whereas serotype 3 was the most common type in the elderly (>65 years). The common serotypes for main IPD diagnoses (invasive pneumonia, meningitis and sepsis) were 19A, 19F and 23F in invasive pneumonia and meningitis, and 19F, 19A, 5, 1 and 23F in sepsis.Conclusion: Serotypes 19A and 3 were the most prominent serotypes in pediatric and adult patients with IPD, respectively. Findings demonstrate the different serotype distribution among various age groups in Chinese population with IPD.Conflict of interest