Invasive Pneumococcal Disease Cases In Children Research Articles

1735. Impact of Children Universal Pneumococcal Vaccination (PCV7v/PCV13v) on Pneumococcal Invasive Disease Hospitalizations in a Private General Hospital, Uruguay

Abstract Background In 2008 Uruguay included pneumococcal conjugate vaccine (PCV) 7valent in children´s vaccination program (2+1). In 2010 PCV13 replaced PCV7. Since 2015, adults at risk of invasive pneumococcal disease (IPD) may receive 23 valent polysaccharide vaccine (PV23) or combined schedule PCV13+PV23. Objective: to assess the impact of this strategy on IPD hospitalization. Methods Rates per 10,000 discharges (Confidence Interval 95 %), diseases and serotypes (ST) are described before PCV7 vaccination (2006-2007), the year of vaccine implementation (2008), early after implementation (2009-2015) and late after implementation (2016-2022), the last 3 years during COVID-19 pandemic. Results In 2006-2022 were 33 IPD cases in children and 88 in adults over 15 years old. Children´s hospitalization median annual rates were as follow 2006-2007: 50 (25-75); 2008: 18,5 (-2-39); 2009-2015: 8,5 (3-14); 2016-2022: 4 (0-8); percentages of rate reduction were 82,5% and 92% (p< 0.0000). In adults 2006-2007: 17 (10-25); 2008: 13,4 (4,62-22,1); 2009-2015: 6,6 (4,4-9); 2016-2022: 6 (3,5-8,5); percentages of rate reduction were 63,5% and 66 % (p= 0,0001). Pneumococcal pneumonia (PP) was the most frequent disease in children 22/33 (66,6%), followed by bacteremia 8/32. PP was also in adults 68/88 (77.2,7%), followed by meningitis (7/88). One non vaccinated child died in 2008. Case fatality rate in adults was 9% (8/88), 3 died in 2006-2007, 2 in 2009-20215 and 3 in 2016-2022. 24 different ST were isolated in adults. Most frequent ST were 12F(15), 7F(11), 1(8), 8(7), 3(6) and 5(6). PCV13 would cover 38/88 (43%). A significant decline in PCV13 serotypes (PCV13-ST) was observed comparing the period prior PCV 17/22 (77%) with the late period 8/24 (34%) (p< 0.0000). 15 different ST were isolated in children: 26 PCV13-ST. 16 prior 2008: most frequent ST 1(5), 14(4), 3(2) and 5(2). In 2009-2022 13 hospitalizations; PCV13-ST: 1(2), 19A(2), 14(1), 6B< (1), 9V(1), 3(1) and non PCV13-ST: 7B/C(1), 24F(1), 13(1), 15A(1), 15B(1). A significant decline of PCV13-ST was observed comparing the period prior PCV (15/16, 94%) with the late period (2/4, 50 %) (p< 0.0000). Conclusion There was a reduction in children’s discharge rates and in adults´ probably due to herd effect. Adult vaccination will improve individual immunization. Disclosures María Catalina Pírez, Pediatrician, Pediatric infectologist, microbiologist Professor of pediatric, Degree V, Merck, Pfizer: Expert Testimony|Merck, Pfizer: Honoraria

A case series of invasive pneumococcal disease in children

Invasive pneumococcal disease (IPD) has a high clinical burden, particularly among children in developing countries. We presented 4 cases of IPD in children who were admitted to Pushpagiri institute of medical science and research centre, Kerala between 2021 and 2022. While our first 3 patients had milder course of disease, our fourth patient who presented with severe pneumonia with pleural effusion had poor outcome. The fact that three out of four of our patients have not received pneumococcal vaccination marks the necessity of this vaccine to prevent IPD in children.

576. Burden of Pneumococcal Disease Due to Serotypes Covered by the 13-Valent and New Higher-Valent Pneumococcal Conjugate Vaccines in All Children and Children at Risk in the United States

Abstract Background Routine vaccination with 13-valent pneumococcal conjugate vaccine (PCV13) in infants along with a catch-up option with PCV13/PPSV23 in children with underlying medical conditions (UMC) have considerably reduced invasive pneumococcal disease (IPD) and non-invasive pneumococcal disease (PD), including community acquired pneumonia (CAP) and acute otitis media (AOM), in the United State (US). However, a rise in IPD and non-invasive PD caused by non-PCV13 serotypes has been observed. A 15-valent PCV (PCV15) and 20-valent PCV (PCV20), containing additional serotypes to PCV13, are anticipated for children soon. The objective of the study was to estimate the annual cases, deaths, and economic burden of disease attributable to PCV13, PCV15, and PCV20 serotypes in children < 18 years old overall and those with UMC in the US. Methods Estimated annual cases, deaths and direct medical costs associated with PD caused by PCV13, PCV15 and PCV20 serotypes were calculated based on published incidence rates of IPD, CAP, and AOM, along with age-group specific serotype coverage, case fatality rates, and disease-related costs (Table 1). The PD burden in those with UMC were extrapolated based on incidence rate ratios of those with UMC vs. those without UMC. The results were reported for 0-17 years and were further stratified into 2 age groups: 0-4 and 5-17 years. Table 1:Source Data for the Calculation Results The estimated annual PD cases attributable to PCV13, PCV15, and PCV20 serotypes in those 0-17 years were 768,301, 1,275,187, and 1,656,716 and in those with UMC were 23,209, 43,579, 63,949 (Table 2.1), respectively. The estimated direct medical costs were $494, $833, $1,103 million in those 0-17 years, and $76, $127, and $186 million in those with UMC, respectively (Table 3.1). The total estimated IPD cases in children with UMC were 18% (PCV13), 20% (PCV15) and 23% (PCV20) of all estimated IPD cases in all children. Conclusion This study demonstrates that the clinical and economic burden associated with new serotypes included in higher valent PCVs are substantial and higher in children with UMCs. The result shows that PCV20 will offer broader PCV coverage in the prevention of PD in ages < 18 years overall and those specifically with UMC. Disclosures Alejandro D. Cane, MD, PhD, Pfizer: Full time employee|Pfizer: Stocks/Bonds Johnna Perdrizet, MPH, Pfizer Inc: Employee|Pfizer Inc: Stocks/Bonds Adriano Arguedas, Medical director, Pfizer: Stocks/Bonds.

Distribution of Serotypes Causing Invasive Pneumococcal Disease in Children From High-Income Countries and the Impact of Pediatric Pneumococcal Vaccination.

The introduction and adoption of pneumococcal conjugate vaccines (PCVs) into pediatric national immunization programs (NIPs) has led to large decreases in invasive pneumococcal disease (IPD) incidence caused by vaccine serotypes. Despite these reductions, the global IPD burden in children remains significant. We collected serotype-specific IPD data from surveillance systems or hospital networks of all 30 high-income countries that met inclusion criteria. Data sources included online databases, surveillance system reports, and peer-reviewed literature. Percentage of serotyped cases covered were calculated for all countries combined and by PCV type in the pediatric NIP. We identified 8012 serotyped IPD cases in children <5 or ≤5 years old. PCV13 serotype IPD caused 37.4% of total IPD cases, including 57.1% and 25.2% for countries with PCV10 or PCV13 in the pediatric NIP, respectively, most commonly due to serotypes 3 and 19A (11.4% and 13.3%, respectively, across all countries). In PCV10 countries, PCV15 and PCV20 would cover an additional 45.1% and 55.6% of IPD beyond serotypes contained in PCV10, largely due to coverage of serotype 19A. In PCV13 countries, PCV15 and PCV20 would cover an additional 10.6% and 38.2% of IPD beyond serotypes contained in PCV13. The most common IPD serotypes covered by higher valency PCVs were 10A (5.2%), 12F (5.1%), and 22F and 33F (3.5% each). Much of the remaining IPD burden is due to serotypes included in PCV15 and PCV20. The inclusion of these next generation PCVs into existing pediatric NIPs may further reduce the incidence of childhood IPD.

Invasive pneumococcal disease in children with cancer: Incidence density, risk factors and isolated serotypes

BackgroundPediatric oncology patients (POP) have a high risk of infections due to impaired immunity. Invasive pneumococcal disease (IPD) is an important cause of severe infection in these patients and it is associated with high mortality. This study aimed to evaluate the incidence and risk factors associated with IPD at a Pediatric Oncology Center in Brazil. MethodsThis was a retrospective case-control study. All IPD cases in children with cancer from 2005 through 2016 were reviewed. Each case of IPD was matched with two controls from a cohort of patients matched for year of IPD, age and disease in order to assess risk factors. The incidence density was calculated as the number of IPD per 100,000 patients-year. ResultsA total of 51 episodes of IPD in 49 patients was identified. All pneumococci were isolated from blood cultures. The median age was five years and 67% were male; mortality rate was 7.8%. The IPD incidence density rate in POP was 311.21 per 100,000 patients-year, significantly higher than the rate in the general pediatric population. Severe neutropenia was the only risk factor associated with IPD, after multivariate conditional logistic regression analysis. ConclusionAlthough pneumococcal disease decreased after the introduction of 10-valent pneumococcal vaccine in the Brazilian national immunization schedule in 2010, there was no decrease in the IPD incidence rate in our cohort. A higher coverage rate of pneumococcal vaccination in children in the general population might be necessary to reduce the incidence rate in this high-risk population.

Characteristics of Serotype 3 Invasive Pneumococcal Disease before and after Universal Childhood Immunization with PCV13 in Massachusetts.

Background: Although a substantial decline in vaccine-serotype invasive pneumococcal disease (IPD) incidence was observed following the introduction of pneumococcal conjugate vaccines (PCV), the estimated range of thirteen-valent conjugate vaccine (PCV13) effectiveness for serotype 3 disease is wide and includes zero. We assessed the impact of PCV13 on serotype 3 IPD incidence and disease characteristics in Massachusetts’ children. Methods: Serotype 3 IPD cases in children <18 years old were identified via enhanced passive surveillance system in Massachusetts. We compared incidence rates and characteristics of IPD cases before and after PCV13. Results: A total of 47 serotype 3 IPD cases were identified from 2002 to 2017; incidence of serotype 3 IPD in the years following PCV13 was 0.19 per 100,000 children compared to 0.21 before PCV 13, incidence rate ratio (IRR) = 0.86 (95% CI 0.47–1.57). The majority (78%) of post-PCV13 serotype 3 IPD cases occurred among fully vaccinated children. Age distribution, clinical syndrome and presence of comorbidities among serotype 3 IPD cases were similar before and after PCV13 introduction. There was no association between the date of the last PCV13 dose and time to IPD to suggest waning of immunity. Conclusions: seven years following PCV 13 we found no significant changes in serotype 3 IPD incidence or disease characteristics in children in Massachusetts.

Serotype distribution and antimicrobial resistance patterns of invasive pneumococcal disease isolates from children in mainland China-a systematic review.

This study aimed to review and report the serotype distribution and antimicrobial resistance patterns of invasive pneumococcal disease (IPD) isolates, as this information is important for policy making since China has not adopted any pneumococcal vaccines in the national immunization schedule. A systematic review of the published literature from January 2000 to December 2018 was performed to identify articles that describe the serotype and/or antimicrobial resistance patterns of IPD cases in children in mainland China. Analysis of the extracted data was performed with the Microsoft Excel spreadsheet program. The percentage of the serotypes was calculated by dividing the number of isolates for each serotype with the total number of isolates included in all the studies. The theoretical impact of the vaccine was estimated by calculating the percentage of isolates that exhibited the serotypes included in the vaccines. The prevalence of antimicrobial resistance was defined as the number of isolates that were resistant divided by the total number of isolates tested for resistance to the specific antimicrobial agent. Forty-two articles were screened in the preliminary search, of which sixteen fulfilled inclusion criteria and were included in the final analysis. The predominant serotypes were 19A, 19F, 14, 23F, and 6B, and the estimated impact of PCV13 was 90.4%. The isolates exhibited a high frequency of resistance to cefuroxime, cefaclor, and erythromycin. It is necessary for Chinese children to receive PCV13. Clinical workers should pay attention to the high frequency of resistance to antimicrobial agents.

Invasive pneumococcal disease in Northern Alberta, not a Red Queen but a dark horse

BackgroundThe consequences of the introduction of various pneumococcal protein conjugate vaccines (PCV) for children and adults is poorly understood. ObjectiveWe undertook a population-based cohort study of invasive pneumococcal disease (IPD) in Northern Alberta (Canada) from 2000 to 2014, years spanning pre-and early PCV (2000–2004) vs PCV-7 (2005–2009) vs PCV-13 (2010–2014) time periods. DesignWe collected clinical, laboratory, and Streptococcus pneumoniae serotype information on all patients from 2000 to 2014. We determined changes in presentation, outcomes, serotypes, and incidence in children and adults across time periods. SettingThere were 509 cases of IPD in children, an 80% decrease over time. Rates of empyema (4.0–15.7%, p < 0.001), ICU admission (13.1–20%), and mortality (1.8–8.4%, p < 0.001) increased over time. There were 2417 cases of IPD in adults. Unlike children, incidence of IPD did not change nor did rates of empyema. ICU admissions increased (p = 0.004) and mortality decreased (18.7–16.5%, p = 0.002). The total number of serotypes causing IPD remained stable in children (22 vs 26 vs 20) while they decreased in adults (49 vs 47 vs 42). Conclusions and relevanceFor children, PCV vaccination strategies resulted in decreased overall rates of IPD and we observed increased rates of empyema and mortality; for adults, there was no change in IPD rates although disease severity increased while mortality decreased. On a population-wide basis, our results suggest that current PCV vaccination strategies are associated with an overall decrease in IPD but disease severity seems to be increasing in both children and adults.

Incidence of invasive pneumococcal disease before and during an era of use of three different pneumococcal conjugate vaccines in Quebec

BackgroundIn Quebec, 7-valent (PCV7), 10-valent (PCV10) and 13-valent (PCV13) pneumococcal conjugate vaccines were successively used for the immunization of children according to a 2+1 doses schedule. ObjectiveOur aim was to assess the impact of this program on the epidemiology of invasive pneumococcal disease (IPD) in children and adults. MethodsNotification and laboratory surveillance data were analyzed and the immunization status of IPD cases in children was checked. ResultsIn children < 5 years, the IPD rate decreased from 69/100,000 in 2003 to 12/100,000 in 2016 (83% reduction). Following PCV7 introduction in 2004, there has been a rapid decline in PCV7-type IPD cases and 6A. 7F and 19A serotypes emerged but their incidence decreased following PCV10 introduction in 2009 and PCV13 in 2011, whereas decrease in serotype 3 IPD was modest. Non-PCV13 types increased and represented 79% of cases in 2016. The same pattern was seen in adults but replacement was complete and there was no decrease in overall IPD rate. In those 65 years and over, PCV13 serotypes represented 28% of cases in 2016 and 62% were serotypes included in the 23-valent polysaccharide vaccine. Out of 10 IPD cases caused by serotype 3 in children vaccinated with PCV13 in 2011–2016, 6 occurred more than one year following the booster dose, which suggests short-term protection. Out of 31 breakthrough 19A cases, 19 occurred in children aged between 8 and 14 months who had received the 2 primary PCV13 doses but not the toddler booster dose, which suggests a window of susceptibility in a 2+1 schedule. ConclusionPCVs had a major impact on the IPD rate in children but not in adults. Among elderly adults, the proportion of cases caused by serotypes included in PCV13 is diminishing year after year but a majority of cases remains covered by the 23-valent polysaccharide vaccine.

Invasive Pneumococcal Disease in Children With Sickle Cell Anemia

Research Article| November 01 2017 Invasive Pneumococcal Disease in Children With Sickle Cell Anemia AAP Grand Rounds (2017) 38 (5): 57. https://doi.org/10.1542/gr.38-5-57 Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Cite Icon Cite Search Site Citation Invasive Pneumococcal Disease in Children With Sickle Cell Anemia. AAP Grand Rounds November 2017; 38 (5): 57. https://doi.org/10.1542/gr.38-5-57 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search toolbar search search input Search input auto suggest filter your search All PublicationsAll JournalsAAP Grand RoundsPediatricsHospital PediatricsPediatrics In ReviewNeoReviewsAAP NewsAll AAP Sites Search Advanced Search Topics: invasive pneumococcal disease, sickle cell anemia Source: Martin OO, Moquist KL, Hennessy JM, et al. Invasive pneumococcal disease in children with sickle cell disease in the pneumococcal conjugate vaccine era. Pediatr Blood Cancer. 2017 4 July [published online ahead of print]; doi: https://doi.org/10.1002/pbc.26713Google Scholar Investigators from Michigan State University, Flint, MI, and Children’s Hospitals and Clinics of Minnesota (CHCM), Minneapolis, MN, conducted a retrospective study to assess trends in invasive pneumococcal disease (IPD) among children with sickle cell disease (SCD) in the era of universal pneumococcal immunization for young children. For the study, they reviewed medical records and microbiological databases at CHCM to identify cases of IPD in children with SCD between 2000 and 2014. IPD was defined as the presence of pneumococcus in a blood or cerebrospinal fluid culture. Data collected on study patients included age, pneumococcal immunization status, pneumococcus serotype, and penicillin susceptibility. On the basis of the number of cases identified and the population of patients with SCD followed up at CHCM, the investigators estimated the incidence of IPD per 100,000 person-years among children with SCD. In addition to describing clinical characteristics of cases of IPD over the entire study period, observations were divided into 2 periods on the basis of the type of pneumococcal conjugate vaccine available. Thus, in period 1, 2000–2010, the pneumococcal conjugate vaccine (PCV) against 7 serotypes (PCV7) was available, and in period 2, 2010–2014, the 13-valent PCV (PCV13) was used. During the overall study period, 11 cases of IPD in patients with SCD were identified, including 7 in period 1 and 4 in period 2. The mean age of study patients was 5 years, with a range of 6 months to 11 years. Two children with IPD died; information on pneumococcus serotype was available for the remaining 9 patients. PCV data were available for 8 of these 9 children, and data for all 8 were classified as being up to date. During period 1, all cases of IPD were caused by serotypes of pneumococcus not included in PCV7; during period 2, 1 patient (an 8-year-old boy) had IPD caused by serotype 7F (included in PCV13 but not PCV7). All isolates tested (n = 9) were sensitive to penicillin. The overall incidence of IPD in children with SCD in this study was estimated at 417 per 100,000 patient-years, with an incidence of 390 per 100,000 patient-years in period 1 and 450 per 100,000 patient-years in period 2. The authors conclude that even in the era of universal pneumococcal immunization, children with SCD remain at risk for IPD. Dr Winer has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device. When considering a prophylactic intervention, one must take into account both the burden of the potential disease and the effect of the proposed intervention. In this brief report, the authors argue for both penicillin and PCV prophylaxis in patients with SCD <5 years of age, which is the... You do not currently have access to this content.

Serotype distribution of Streptococcus pneumoniae causing invasive disease in children in the post-PCV era: A systematic review and meta-analysis.

BackgroundRoutine immunisation with pneumococcal conjugate vaccines (PCV7/10/13) has reduced invasive pneumococcal disease (IPD) due to vaccine serotypes significantly. However, an increase in disease due to non-vaccine types, or serotype replacement, has been observed. Serotypes’ individual contributions to IPD play a critical role in determining the overall effects of PCVs. This study examines the distribution of pneumococcal serotypes in children to identify leading serotypes associated with IPD post-PCV introduction.MethodsA systematic search was performed to identify studies and surveillance reports (published between 2000 and December 2015) of pneumococcal serotypes causing childhood IPD post-PCV introduction. Serotype data were differentiated based on the PCV administered during the study period: PCV7 or higher valent PCVs (PCV10 or PCV13). Meta-analysis was conducted to estimate the proportional contributions of the most frequent serotypes in childhood IPD in each period.ResultsWe identified 68 studies reporting serotype data among IPD cases in children. We analysed data from 38 studies (14 countries) where PCV7 was administered and 20 (24 countries) where PCV10 or PCV13 have been introduced. Studies reported early and late periods of PCV7 administration (range: 2001∓13). In these settings, serotype 19A was the most predominant cause of childhood IPD, accounting for 21.8% (95%CI 18.6∓25.6) of cases. In countries that have introduced higher valent PCVs, study periods were largely representative of the transition and early years of PCV10 or PCV13. In these studies, the overall serotype-specific contribution of 19A was lower (14.2% 95%CI 11.1∓18.3). Overall, non-PCV13 serotypes contributed to 42.2% (95%CI 36.1∓49.5%) of childhood IPD cases. However, regional differences were noted (57.8% in North America, 71.9% in Europe, 45.9% in Western Pacific, 28.5% in Latin America, 42.7% in one African country, and 9.2% in one Eastern Mediterranean country). Predominant non-PCV13 serotypes overall were 22F, 12F, 33F, 24F, 15C, 15B, 23B, 10A, and 38 (descending order), but their rank order varied by region.ConclusionChildhood IPD is associated with a wide number of serotypes. In the early years after introduction of higher valent PCVs, non-PCV13 types caused a considerable proportion of childhood IPD. Serotype data, particularly from resource-limited countries with high burden of IPD, are needed to assess the importance of serotypes in different settings. The geographic diversity of pneumococcal serotypes highlights the importance of continued surveillance to guide vaccine design and recommendations.

Global Pneumococcal Disease and Policies for Control

Global Pneumococcal Disease and Policies for Control

Invasive pneumococcal diseases in birth cohorts vaccinated with PCV-7 and/or PHiD-CV in the province of Quebec, Canada

BackgroundThe 10-valent protein D pneumococcal conjugate vaccine (PHiD-CV) was licensed on the basis of immunogenicity studies and there are no published data on its effectiveness to prevent invasive pneumococcal disease (IPD). In the province of Quebec, Canada, PHiD-CV was introduced in the summer of 2009, replacing the 7-valent CRM197 vaccine (PCV-7). Transition to the new vaccine was recommended regardless of the number of PCV7 doses already administered. MethodsIPD rates in children born in 2007–2010 and observed up to the end of 2010 were computed from laboratory surveillance data. The main vaccine used for the infant primary immunization series (mainly 2 doses at 2–4 months) and the toddler (12 months) booster dose was inferred from the Quebec City Immunization Registry data. ResultsIPD rates were significantly lower in the cohorts exposed to PHiD-CV (35/100,000 person-years) as compared with those exposed to PCV-7 (64/100,000person-years; p=0.03). There was no breakthrough vaccine-type IPD case among children who had received ≥2 PHiD-CV doses for the primary series or a single PHiD-CV dose as a booster. There was also a statistically non-significant lower frequency of 19A and other non-vaccine types IPD cases in children exposed to 2+1 PHiD-CV doses as compared with those exposed to PCV-7. InterpretationResults are compatible with a high level of protection induced by PHiD-CV against IPD caused by homologous serotypes.

Invasive Pneumococcal Disease a Decade after Pneumococcal Conjugate Vaccine Use in an American Indian Population at High Risk for Disease

Before 7-valent pneumococcal conjugate vaccine (PCV7) introduction, invasive pneumococcal disease (IPD) rates among Navajo were several-fold those of the general US population. Only 50% of IPD cases in children involved PCV7 serotypes. We conducted active, population-based surveillance for IPD for the period 1995-2006. We documented case characteristics and serotyped the isolates. Over 12-year period, we identified 1508 IPD cases, 447 of which occurred in children aged <5 years. Rates of IPD due to vaccine serotypes among children aged <1 year, 1 to <2 years, and 2 to <5 years decreased from 210, 263, and 51 cases per 100,000 population, respectively in 1995-1997 to 0 cases in 2004-2006 (P < .001). Among adults aged > or =65 years, rates of IPD due to vaccine serotypes decreased 81% (95% confidence interval, -98% to -9%; P = .02). Rates of nonvaccine serotype IPD were unchanged in all age strata except for persons aged 18 to <40 years, among whom the rate decreased by 35% from 27 to 18 cases per 100,000 population (95% confidence interval, -57% to -1%; P = .03). Vaccine-serotype IPD has virtually been eliminated in the PCV7 era among Navajo of all ages. Overall rates of nonvaccine-serotype IPD have not increased, although increases have occurred for some individual types. Rates of all-serotype IPD among Navajo children remain 3-5-fold greater than in the general US population.

Changes in serotypes causing invasive pneumococcal disease (2005–2007 vs. 1997–1999) in children under 2 years of age in a population with intermediate coverage of the 7-valent pneumococcal conjugated vaccine

Serotypes causing invasive pneumococcal disease (IPD) in children aged <2 years in Catalonia (Spain) before and after licensing of the 7-valent pneumococcal conjugated vaccine (7vPCV) were assessed, using samples taken during 1997–1999 and 2005–2007 respectively. The distribution of serotypes causing IPD within these groups was obtained by serotyping strains sent by 22 Catalan hospitals to the Carlos III Health Institute, Madrid. Between 1997–99 and 2005–2007, the proportion of vaccine serotypes causing IPD in Catalonia fell from 70.54% to 31.67% (p <0.0001). The proportion of vaccine-related serotypes, mainly serotype 19A, increased from 9.82% to 32.50% (p <0.0001). The proportion of non-vaccine, non-related serotypes (serotypes not related to vaccine serotypes) rose from 19.64% to 35.83% (p <0.05). Within this group, the proportions of serotype 24F increased significantly. There has been a change in the distribution of serotypes isolated from cases of IPD in children <2 years old in Catalonia, comprising a reduction in the proportion of 7-valent vaccine serotypes, a rise in vaccine-related serotypes, especially 19A, and a smaller rise in non-vaccine, non-related serotypes, especially serotype 24F. A new 13-valent vaccine will cover 77.91% of the serotypes causing IPD in children <2 years old in Catalonia from 2005 to 2007.

Impacto de la vacuna neumocócica conjugada heptavalente en una población con valores bajos-intermedios de vacunación

To analyze the changes occurring in declared cases (microbiological report) of invasive pneumococcal disease (IPD) in children <2 years old in Catalonia (Spain) after the 7-valent pneumococcal conjugate vaccine (PCV7) was licensed for use. Cases of IPD in children <2 years old were obtained from notifications to the Microbiological Reporting System of Catalonia (MRSC) in 1997-1999 and 2002-2004 by the hospitals (n=23) that have participated in the MRSC continuously and uninterruptedly since its inception in 1995. Overall reported rates were 49.2 cases per 100,000 persons-year in 1997-1999 and 40.4 per 100,000 persons-year in 2002-2004; the difference was not statistically significant. The rate of bacteremic pneumonia fell from 25.2 per 100,000 persons-year in 1997-1999 to 21.6 per 100,000 persons-year in 2002-2004, and meningitis from 6.0 to 4.3 per 100,000 persons-year; again, differences were not statistically significant (P>0.05). After PCV7 was licensed for use, a noticeable, but non-significant, reduction in reported IPD rates in children <2 years old occurred in Catalonia. If the results had been statistically significant, the overall reduction would have been 17.90%, not far below the theoretically expected reduction (22%), based on the protective efficacy of PCV7 (89%), the percentage of invasive disease-causing serotypes included in the vaccine (70%), and the vaccination coverage achieved during the study period (35%).

Invasive pneumococcal disease in Danish children, 1996–2007, prior to the introduction of heptavalent pneumococcal conjugate vaccine

The aim of this study was to document the epidemiology, microbiology and outcome of invasive pneumococcal disease (IPD) among children <16 years with quality surveillance data, just prior to the introduction of the heptavalent pneumococcal conjugate vaccine (PCV7) into the Danish routine immunization programme October 2007. Clinical and microbiological records on cases of IPD in children <16 years admitted to Hvidovre Hospital, Denmark 1996-2007, were retrospectively reviewed. We identified 106 cases of IPD. The annual incidence of IPD was 11 per 100 000 in children <16 years, but considerably higher, 62 per 100 000, in children <2 years. Additionally, of the children with pneumococcal meningitis 86% were <2 years. We observed no fatalities. A total of 10% developed sequelae, but of the patients with pneumococcal meningitis 27% developed sequelae. Nine patients had known risk factors. The Streptococcus pneumoniae serotype was available for 81 cases. Seventy-five percent of the IPD cases in children aged <2 years were caused by one of the serotypes contained within PCV7, compared to only 24% in children >/=2 years. Our data indicate that an estimated 75% of all IPD cases among children <2 years are caused by PCV7 serotypes and might therefore be prevented by PCV7 vaccination.

Serotype 19A S. pneumoniae: A Growing Problem for Children

Introduction of heptavalent pneumococcal conjugate vaccine (PCV7) in the U.S. in 2000 was followed by a reduction in the rate of invasive pneumococcal disease (IPD) among young children (see Journal Watch Infectious Diseases May 23 2003). The seven serotypes contained in this vaccine are estimated to cause 80% to 85% of IPD cases in children. Recently, type 19A (which is not included in PVC7) has emerged among Alaska Native children, causing an increase in IPD rates in this population (see Journal Watch Infectious Diseases May 2 2007). Two recent reports alert us to the growing threat from Streptococcus pneumoniae type 19A in the continental U.S. …