Introduction Of PCV7 Research Articles

Increase of Macrolide-Resistance in Streptococcus pneumoniae Strains After the Introduction of the 13-Valent Pneumococcal Conjugate Vaccine in Lima, Peru.

Streptococcus pneumoniae upper respiratory infections and pneumonia are often treated with macrolides, but recently macrolide resistance is becoming an increasingly important problem. The 13-valent pneumococcal conjugate vaccine (PCV13) was introduced in the National Immunization Program of Peru in 2015. This study aimed to evaluate the temporal evolution of macrolide resistance in S. pneumoniae isolates collected in five cross-sectional studies conducted before and after this vaccine introduction, from 2006 to 2019 in Lima, Peru. A total of 521 and 242 S. pneumoniae isolates recovered from nasopharyngeal swabs from healthy carrier children < 2 years old (2 carriage studies) and samples from normally sterile body areas from pediatric patients with invasive pneumococcal disease (IPD) (3 IPD studies), respectively, were included in this study. Phenotypic macrolide resistance was detected using the Kirby-Bauer method and/or MIC test. We found a significant increase in macrolide resistance over time, from 33.5% to 50.0% in carriage studies, and from 24.8% to 37.5% and 70.8% in IPD studies. Macrolide resistance genes [erm(B) and mef(A/E)] were screened using PCR. In carriage studies, we detected a significant decrease in the frequency of mef(A/E) genes among macrolide-resistant S. pneumoniae strains (from 66.7% to 50.0%) after introduction of PCV13. The most common mechanism of macrolide-resistant among IPD strains was the presence of erm(B) (96.0%, 95.2% and 85.1% in the 3 IPD studies respectively). Macrolide resistance was more common in serotype 19A strains (80% and 90% among carriage and IPD strains, respectively) vs. non-serotype 19A (35.5% and 34.4% among carriage and IPD strains, respectively). In conclusion, S. pneumoniae macrolide resistance rates are very high among Peruvian children. Future studies are needed in order to evaluate macrolide resistance trends among pneumococcal strains, especially now after the COVID-19 pandemic, since azithromycin was vastly used as empiric treatment of COVID-19 in Peru.

Effect of childhood vaccination and antibiotic use on pneumococcal populations and genome-wide associations with disease among children in Nepal: an observational study

SummaryBackgroundPneumococcal disease is a leading cause of bacterial pneumonia and invasive bacterial disease among children globally. The reason some strains of pneumococci are more likely to cause disease, and how interventions such as vaccines and antibiotics affect pneumococcal strains is poorly understood. We aimed to identify genetic regions under selective pressure and those associated with disease through the analysis of pneumococcal whole-genome sequences.MethodsWhole-genome sequencing was performed on pneumococcal isolates collected between January, 2005, and May, 2018, in Kathmandu, Nepal, which included programmatic ten-valent pneumococcal conjugate vaccine (PCV10) introduction in 2015. Isolates were from three distinct cohorts: nasopharyngeal swabs of healthy community-based children, nasopharyngeal swabs of children admitted to hospital with pneumonia, and sterile-site cultures from children admitted to hospital. Across these cohorts we examined serotype distribution, antibiotic resistance, strain distribution, and regions of recombination to determine genes that were undergoing diversifying selection. Genome-wide association studies comparing pneumonia and sterile-site isolates with healthy carriage were used to determine novel variants associated with disease.FindingsAfter programmatic introduction of PCV10, there was a decline in vaccine covered serotypes; however, strains that had expressed these serotypes continued to exist in the post-PCV population. We identified GPSC9 to be a strain of concern due to its high prevalence in disease, multidrug resistance, and ability to switch to an unencapsulated phenotype via insertion of virulence factor pspC into the cps locus. Antibiotic resistance loci to co-trimoxazole were found to be prevalent (pre-PCV10 78% vs post-PCV10 81%; p=0·27) and increasingly prevalent to penicillin (pre-PCV10 15% vs post-PCV10 32%; p<0·0001). Regions with multiple recombinations were identified spanning the surface protein virulence factors pspA and pspC and antibiotic targets pbpX, folA, folC, folE, and folP. Furthermore, we identified variants in lacE2 to be strongly associated with isolates from children with pneumonia and PRIP to be strongly associated with isolates from sterile sites.InterpretationOur work highlights the effect of pneumococcal conjugate vaccines, antibiotics, and host–pathogen interaction in pneumococcal variation, and the pathogen's capability of adapting to these factors at both population-wide and strain-specific levels. Ongoing surveillance of disease-associated strains and further investigation of lacE2 and PRIP as serotype-independent targets for therapeutic interventions is required.FundingGavi, The Vaccine Alliance; WHO; Bill & Melinda Gates Foundation; Wellcome Sanger Institute; and US Centers for Disease Control and Prevention.

A Retrospective Analysis to Estimate the Burden of Invasive Pneumococcal Disease and Non-Invasive Pneumonia in Children

Despite advances in preventative interventions, invasive pneumococcal disease and pneumonia cause significant morbidity and mortality in children. We studied the annual incidence of pneumococcal-specific and syndromic invasive disease and non-invasive pneumonia in children <15 years of age during the early (2010–2013) and late (2014–2017) 13-valent pneumococcal conjugate vaccine (PCV13) periods in Veneto, Italy. In this retrospective observational study, pneumococcal-specific and syndromic invasive disease and non-invasive pneumonia cases were identified from several sources, including the Pedianet database. Interrupted time series analysis and Mann–Kendall tests were conducted to explore trends in incidence rates (IRs). Among 72,570 patients <15 years of age between 2010–2017, 88 episodes of pneumococcal-specific and syndromic invasive disease and 3926 episodes of non-invasive pneumonia were reported. Overall IR of pneumococcal-specific and syndromic invasive disease was 0.4/1000 person-years and did not change significantly (p = 0.46) throughout the study. Overall IR of non-invasive pneumonia was 10/1000 person-years and decreased significantly (−0.64, p = 0.026) over the study period. Following PCV13 introduction, the IRs of non-invasive pneumonia in children <15 years of age declined significantly, with no significant change in the IRs of pneumococcal-specific and syndromic invasive disease. There is a continuing clinical burden associated with pediatric pneumococcal diseases in Veneto, Italy.

Impact of Pneumococcal Conjugate Vaccines on Antibiotic-Nonsusceptible Invasive Pneumococcal Disease in the United States.

Antibiotic-nonsusceptible invasive pneumococcal disease (NS-IPD) incidence declined dramatically in the United States after introduction of pneumococcal conjugate vaccines (PCVs) into the infant immunization schedule (7-valent PCV7 in 2000, replaced by the 13-valent PCV13 in 2010). We evaluated the long-term impact of PCVs on NS-IPD. We identified IPD cases through the Centers for Disease Control Active Bacterial Core surveillance during 1998-2018. Isolates intermediate or resistant to ≥1 antibiotic class were classified as nonsusceptible. We calculated annual rates of IPD (cases per 100 000 persons). From 1998 through 2018, NS-IPD incidence decreased from 43.9 to 3.2 among children <5 years and from 19.8 to 9.4 among adults ≥65 years. Incidence of vaccine-type NS-IPD decreased in all age groups, whereas incidence of nonvaccine type (NVT) NS-IPD increased in all age groups; the greatest absolute increase in NVT NS-IPD occurred among adults ≥65 years (2.3 to 7.2). During 2014-2018, NVTs 35B, 33F, 22F, and 15A were the most common NS-IPD serotypes. Nonsusceptible IPD incidence decreased after PCV7 and PCV13 introduction in the United States. However, recent increases in NVT NS-IPD, most pronounced among older adults, have been observed. New higher valency PCVs containing the most common nonsusceptible serotypes, including 22F and 33F, could help further reduce NS-IPD.

Dynamic changes in clinical characteristics and serotype distribution of invasive pneumococcal disease among adults in Japan after introduction of the pediatric 13-valent pneumococcal conjugate vaccine in 2013–2019

Nationwide population-based surveillance for invasive pneumococcal disease (IPD) is being conducted in few Asian countries. We aimed to evaluate the clinical characteristics and serotype distribution among Japanese adult patients with IPD after introduction of the pediatric 13-valent pneumococcal conjugate vaccine (PCV13) in 2013. IPD surveillance was conducted among adults between 2013 and 2019, and 1,995 patients were analyzed by time period (early, 2013–2015; middle, 2016–2017; late, 2018–2019). We found that the period of 2018–2019 was independently associated with a lower risk of fatal outcome, compared with the period of 2013–2015. The proportion of those with serotype PCV13-nonPCV7 decreased significantly in patients aged 15–64 years and in those aged ≥ 65 years within 3 years after the introduction of pediatric PCV13. By contrast, the proportion of those with nonvaccine serotype increased significantly in those aged ≥ 65 years, but not in those aged 15–64 years. No significant change was found in the proportion of 23-valent polysaccharide pneumococcal vaccine (PPSV23)-nonPCV13 in both of adults aged 15–64 years and ≥ 65 years. The proportions of PCV15-, PCV20- and PCV24-covered serotypes were 38%, 56% and 58% in adult patients with IPD aged ≥ 65 years during the late period. Our data on the serotype distribution support an indirect effect from pediatric PCV13 use among adults, and afford a basis for estimates of protection against IPD by vaccination with newly developed PCVs in older adults in Japan.

Healthcare Costs for Pneumococcal Disease in the Era of Infant Immunization With 13-Valent Pneumococcal Conjugate Vaccine: A Population-Based Study

ObjectivesInvasive pneumococcal disease (IPD) and a variety of clinical syndromes caused by pneumococci, such as acute otitis media (AOM), acute sinusitis (AS), and community-acquired pneumonia (CAP), cause a substantial burden on healthcare systems. Few studies have explored the short-term financial burden of pneumococcal disease after the 13-valent pneumococcal conjugate vaccine (PCV13) introduction in the infant immunization programs. This population-based study evaluated changes in costs associated with healthcare utilization for pneumococcal disease after the PCV13 introduction in the infant immunization program in British Columbia, Canada. MethodsIndividuals with pneumococcal disease were identified using provincial administrative data for the 2000 to 2018 period. Total direct healthcare costs were determined using case-mix methodology for hospitalization and fee-for-service codes for outpatient visits and medications dispensed. Costs were adjusted to 2018 Canadian dollars. Changes in the annual healthcare costs were evaluated across vaccine eras (pre-PCV13, 2000-2010; PCV13, 2011-2018) using generalized linear models, adjusting for the 7-valent pneumococcal conjugate vaccine program (2004-2010). ResultsDuring the 19-year study period, pneumococcal disease resulted in 6.3 million cases among 85 million total patient-years, resulting in total healthcare costs of $7.9 billion. More than 6.2 million cases were treated in outpatient setting, costing $0.65 billion (8% of total costs associated with pneumococcal disease treatment), whereas 370 000 hospitalized cases were 3% of all cases, which accrued $7.25 billion (92% of total costs) in costs. Healthcare costs for all studied infections nearly doubled over the study period from $248 million in 2000 to $476 million in 2018 (P = .003). In contrast, there were large declines in total annual costs in the PCV13 era for IPD (adjusted relative rate (aRR) 0.73; 95% confidence interval [CI] 0.56-0.95; P = .032), AOM (aRR 0.70; 95% CI 0.59-0.83; P = .001), and AS (aRR 0.68; 95% CI 0.54-0.85; P = .004) compared with the pre-PCV13 era. Total costs increased marginally in the PCV13 era for all-cause CAP (aRR 1.04; 95% CI 0.94-1.15; P = .484). ConclusionsThis study confirms a temporal association in declining economic burden for IPD, AOM, and AS after the PCV13 introduction. Nevertheless, the total economic burden continues to be high in the PCV13 era, mainly driven by increasing CAP costs.

Clinical and Bacteriological Analysis of Pediatric Pneumococcal Meningitis after 13-Valent Pneumococcal Conjugate Vaccine Introduction in Japan.

ABSTRACTStreptococcus pneumoniae is one of the leading causes of meningitis in children. In Japan, since the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13), the number of pneumococcal meningitis due to non-PCV13 serotypes in children has increased. To clarify the clinical outcomes, serotype distributions, and antimicrobial susceptibility of isolated S. pneumoniae strains from pediatric pneumococcal meningitis, we clinically and bacteriologically analyzed 34 cases of pediatric pneumococcal meningitis that were reported after the PCV13 introduction era in Japan. The median age at diagnosis was 1 year (range: 3 months–13 years). Ten (29.4%) patients had underlying diseases. Twenty-nine (85.3%) patients had received at least one dose of any pneumococcal vaccine. Of the 34 patients with pneumococcal meningitis, 6 had sequelae, and 4 died. Nine (26.5%) strains were resistant to penicillin; five (15%) strains to meropenem, with an MIC of 0.5 μg/mL. All strains were susceptible to vancomycin and linezolid. Daptomycin’s MIC50 was 0.064 μg/mL and MIC90 was 0.094 μg/mL. Among the tested strains, only four were PCV13 serotypes. Penicillin-resistant S. pneumoniae was isolated from 30.0% of the patients with sequelae and death. Particularly, the proportion of serotype 10A in the sequelae and deceased cases was significantly higher than that in the complete recovery cases. We should carefully monitor the serotype and drug susceptibility of S. pneumoniae strains isolated from patients with meningitis after the PCV13 era and reconsider the treatment strategy to prepare against further drug-resistant pneumococcal strains.IMPORTANCE We analyzed 34 cases of pediatric pneumococcal meningitis that were reported after the 13-valent pneumococcal conjugate vaccine (PCV13) introduction era in Japan. Our study revealed that pneumococcal meningitis in children was mainly caused by non-PCV13 serotypes; all cases with sequelae and death were caused by non-PCV13 serotypes. Moreover, all serotypes of penicillin resistant Streptococcus pneumoniae strains (26.5%; 9/34) were non-PCV13 serotypes. We also analyzed antimicrobial susceptibilities of glycopeptides, linezolid (LZD), and daptomycin (DAP) of isolated S. pneumoniae strains. All tested strains were susceptible to vancomycin, teicoplanin, LZD, and DAP. Especially. DAP demonstrated the best outcome among the tested antibiotics, with MIC90 of 0.094 μg/mL. Pneumococcal meningitis in children continues to persist and is difficult to control with the current conjugate vaccines. Therefore, it is important to monitor the serotype and antimicrobial susceptibility of S. pneumoniae strains isolated from patients with meningitis and accordingly reconsider the treatment strategy.

Incidence of acute otitis media in children in the United States before and after the introduction of 7- and 13-valent pneumococcal conjugate vaccines during 1998\u20132018

BackgroundAcute otitis media (AOM) is a leading cause of office visits and antibiotic prescriptions in children. Pneumococcal conjugate vaccines were introduced in the USA in 2000 (7-valent, PCV7) and 2010 (13-valent, PCV13). Expanded valency PCVs are currently under development. To describe the impact of PCVs and quantify the residual burden of AOM, this study estimated annual incidence rates (IRs) of AOM and AOM-related complications and surgical procedures in children < 18 years in the USA before and after the introduction of PCV7 and PCV13.MethodsAOM episodes were identified in the IBM MarketScan® Commercial and Medicaid databases using diagnosis codes (ICD-9-CM: 382.x; ICD-10-CM: H66.xx and H67.xx). Annual IRs were calculated as the number of episodes per 1000 person-years (PYs) for all children < 18 years and by age group (< 2, 2–4, and 5–17 years). National estimates of annual AOM IRs were extrapolated using Census Bureau data. Interrupted time series analyses were used to assess immediate and gradual changes in monthly AOM IRs, controlling for seasonality.ResultsIn the commercially insured population, AOM IRs declined between the pre-PCV7 period (1998–1999) and the late PCV13 period (2014–2018) from 1170.1 to 768.8 episodes per 1000 PY for children < 2 years, from 547.4 to 410.3 episodes per 1000 PY in children 2–4 years, and from 115.6 to 91.8 episodes per 1000 PY in children 5–17 years. The interrupted time series analyses indicated significant immediate or gradual decreases in the early PCV7 period (2001–2005), and gradual increases in the late PCV7 period (2006–2009) in children < 2 years; however, crude IRs trended downward in all time periods. In older children, IRs decreased in the early PCV7 and early PCV13 period (2011–2013), but gradually increased in the late PCV7 period. IRs of AOM-related surgical procedures decreased, and IRs of AOM-related complications increased during the study timeframe.ConclusionsAOM disease burden remains high in children of all ages despite overall reductions in AOM IRs during 1998–2018 following the introduction of PCV7 and PCV13. The impact of investigational PCVs on the disease burden of AOM will likely depend on AOM etiology and circulating pneumococcal serotypes.

Vaccine effectiveness of the 7-valent and 13-valent pneumococcal conjugate vaccines in Canada: An IMPACT study

We used an indirect cohort analysis in children under 5 years-old from 2002 to 2018 to examine vaccine effectiveness (VE) of the 7-valent pneumococcal conjugate vaccine (PCV) (3 + 1 doses in most regions) and the 13-valent PCV (2 + 1 doses in all regions) against invasive pneumococcal disease (IPD) caused by vaccine serotypes in children in Canada. Cases were identified from the Canadian Immunization Monitoring Program ACTive (IMPACT), a national active surveillance network of 12 tertiary care pediatric hospitals that represent about 90% of tertiary care hospital beds in Canada. There were 1477 children evaluated for PCV7 VE and 489 for PCV13 VE. PCV7 VE in children with vaccination up to date for their age was 96% (95% CI: 67–99%) after a single dose and 95% (95% CI: 92–97%) after ≥2 doses. The VE was 91% (95% CI: 85–94%) in children who had received doses but were not up to date for their age. PCV13 VE in children with vaccinations up to date for their age was 55% (95% CI: 28–72%) after ≥2 doses. The PCV13-vaccine serotypes causing breakthrough IPD in children up to date for their age with 2+ doses of PCV13 were 3 (13/27, 48.2%),19A (11/27, 40.7%), and 19F (3/27, 11.1%). When serotype 3 and 19A were excluded, the VE of PCV13 against the remaining vaccine serotypes was 89% (95% CI: 64–97%) in children with ≥2 doses. The lower VE of PCV13 may be due to lower effectiveness against serotypes 3 and 19A, which could be influenced by the change in dosing schedule from 4 to 3 total doses with the introduction of PCV13, combined with vaccine uptake of 80%. However, PCV13 still provides the benefit of protection against more serotypes than PCV7, and good VE against all serotypes except 3 and 19A.

A Retrospective Database Analysis to Estimate the Burden of Acute Otitis Media in Children Aged

This study aimed to assess trends in the incidence of acute otitis media (AOM), a common childhood condition, following the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) in the Veneto region of Italy in 2010. AOM episodes (overall, simple, and recurrent (≥3 or ≥4 episodes in 6 or 12 months, respectively, with ≥1 episode in the preceding 6 months)) in children <15 years of age were identified in Pedianet from 2010–2017. Interrupted time series analyses were conducted to assess changes in the annual incidence rates (IRs) in early (2010–2013) and late (2014–2017) PCV13 periods. In total, 72,570 children (402,868 person-years) were identified; 21,048 had 41,683 AOM episodes. Mean annual AOM IR was 103/1000 person-years (95% confidence interval: 102–104), decreasing from 126 to 79/1000 person-years. AOM IRs were highest in children 2–4 years of age, followed by <2 and 5–14 years of age. Overall and simple AOM IRs decreased among children 0–14 years of age, including 2–4 and 5–14 years of age, while recurrent AOM IRs decreased in children <2 years of age. Following PCV13 introduction, AOM IRs decreased substantially in children <15 years of age, with the greatest benefit observed in older children, driven by a reduction in simple AOM IRs. AOM disease burden remains substantial.

The Impact of the 13-Valent Pneumococcal Conjugate Vaccine on Otitis Media-Related Antibiotic Use Among Young Children in Tennessee, USA.

Otitis media (OM) is a leading cause of pediatric antibiotic use. Introduction of the 13-valent pneumococcal conjugate vaccine (PCV13) led to reductions in OM among US children, though its impact on OM-related antibiotic use remains unclear. Among 499 683 Tennessee children <2 years of age, the OM-related antibiotic fill rate was stable after PCV13 introduction.

The economic impact of the switch from single- to multi-dose PCV13 vial in Benin

BackgroundLittle is known on the economic implications of multi-dose 13 valent pneumococcal conjugate vaccine (PCV13) introduction in expanded program on immunization (EPI). Based on evidence of PCV13’s reduced pressure on vaccine cold chain, Benin, a third world country in West Africa, introduced the multi-dose PCV13 starting in April 2018 in its EPI program in replacement of the single-dose presentation. The objective of this study was to conduct a rapid assessment of the costs and economic impact of switching from single- to multi-dose PCV13 vial in Benin.MethodsThe data collected retrospectively between January 1 and February 16, 2019 using a quantitative questionnaire was analyzed using Excel 2010 and Stata 13. Resources consumed from April 1st to September 30th, 2017 for the single-dose PCV13 and from April 1st to September 30th, 2018 for multi-dose were analyzed. For both presentations, costs analyzed included vaccines, injections supplies, waste management, cold chain, personnel (salaries and per diems), supervision and monitoring, training, social mobilization and overheads. Moreover, additional costs incurred for the introduction of multi-dose PCV13 were also collected. Costs were estimated for each presentation of PCV13 vaccine by calculating the half-year value of recurrent and capital costs, discounted at a rate of 3% for capital items. To enable comparisons, costs pertaining to 2017 were converted to 2018 equivalent values taking inflation in US$ into account.ResultsThe economic costs of the single-dose PCV13 exceeded that of the multi-dose: US$ 3,708,795 versus US$ 3,698,795, respectively. Three cost items, including costs of vaccines, injection supplies, and cold chain appeared to be the main drivers of the observed reduction in costs of multi-dose PCV13. Moreover, the cost per infant vaccinated was lower with the single-dose PCV13 than the multi-dose, respectively US$ 6.28 versus US$ 10.92, and costs of vaccines wasted higher for the multi-dose PCV13.ConclusionsThis evaluation seemed to show that the switch from single- to multi-dose PCV13 resulted in reduced economic costs of PCV13. Vaccinating more infants together with a rigorous application of vaccine open vial policy could lead to the change being more cost-effective.

Pneumococcal conjugate vaccination schedules in infants\u2014acquisition, immunogenicity, and pneumococcal conjugate and yellow fever vaccine co-administration study

BackgroundPneumococcal conjugate vaccines (PCVs) effectively prevent pneumococcal disease, but the global impact of pneumococcal vaccination is hampered by its cost. The evaluation of reduced dose schedules of PCV includes measurement of effects on immunogenicity and carriage acquisition compared to standard schedules. The relevance and feasibility of trials of reduced dose schedules is greatest in middle- and low-income countries, such as The Gambia, where the introduction of PCV resulted in good disease control but where transmission of vaccine-type pneumococci persists. We designed a large cluster-randomised field trial of an alternative reduced dose schedule of PCV compared to the standard schedule, the PVS trial. We will also conduct a sub-study to evaluate the individual-level effect of the two schedules on carriage acquisition, immunogenicity, and co-administration of PCV with yellow fever vaccine, the PVS-AcqImm trial.MethodsPVS-AcqImm is a prospective, cluster-randomised trial of one dose of PCV scheduled at age 6 weeks with a booster dose at age 9 months (i.e. alternative ‘1+1’ schedule) compared to three primary doses scheduled at 6, 10, and 14 weeks of age (i.e. standard ‘3+0’ schedule). Sub-groups within the alternative schedule group will receive yellow fever vaccine separately or co-administered with PCV at 9 months of age. The primary endpoints are (a) rate of nasopharyngeal vaccine-type pneumococcal acquisition from 9 to 14 months of age, (b) geometric mean concentration of vaccine-type pneumococcal IgG at 18 months of age, and (c) proportions with yellow fever neutralising antibody titre ≥8 four weeks after administration of yellow fever vaccine. Participants and field staff will not be masked to group allocation while the measurement of laboratory endpoints will be masked. Approximately equal numbers of participants will be resident in each of 28 geographic clusters (14 clusters in alternative and standard schedule groups); 784 enrolled for acquisition measurements and 336 for immunogenicity measurements.DiscussionAnalysis will account for potential non-independence of measurements by cluster and so interpretation of effects will be at the individual level (i.e. a population of individuals). PVS-AcqImm will evaluate whether acquisition of vaccine-type pneumococci is reduced by the alternative compared to the standard schedule, which is required if the alternative schedule is to be effective. Likewise, evidence of superior immune response at 18 months of age and safety of PCV co-administration with yellow fever vaccine will support decision-making regarding the use of the alternative 1+1 schedule. Acquisition and immunogenicity outcomes will be essential for the interpretation of the results of the large field trial comparing the two schedules.Trial registrationInternational Standard Randomised Controlled Trial Number 72821613.

The impact of pneumococcal conjugate vaccine on the prevalence and severity of hospitalizations for pneumonia in children.

Pneumococcal conjugate vaccines (PCV) were introduced into the Israeli national immunization plan starting with the heptavalent PCV7 in 2009 and then PCV13 in the late 2010. The objective of this study was to determine the vaccines' impact on hospitalization rates for community-acquired pneumonia on the severity of the pneumonia episodes and upon pneumococcal serotype distribution. We retrospectively reviewed all children hospitalized in our institution with pneumonia, aged between 1 and 16years, between the years 2006 and 2015. Demographic, clinical, and laboratory data between three time periods: pre-PCV, PCV7, and PCV13, were compared. During the study period, 1375 children were hospitalized with pneumonia. A gradual decline in hospitalization rates due to pneumonia was observed starting in 2006 in the pre-PCV period and continued until after the introduction of PCV13. A similar trend was observed in pneumonias with a culture positive for S. pneumoniae. Pleural effusion was observed in 24% of all pneumonias, and this percentage was stable throughout the study period. The average age at hospitalization increased during the study period, as did the average duration of hospital stay. Pneumococcal serotypes included in the vaccine were isolated less frequently during the study and non-vaccine serotypes tended to appear more frequently. Pediatric pneumonia hospitalization rates continued to decline since the introduction of PCV without increasing the frequency of complications. Pneumococcal serotype distribution shifted in parallel. Our findings confirm the efficacy of PCV and support the evidence to include more serotypes in the next generation of PCV.

Evolution of pneumococcal serotype epidemiology in Botswana following introduction of 13-valent pneumococcal conjugate vaccine.

Pneumococcal conjugate vaccines reduce the burden of invasive pneumococcal disease, but the sustained effect of these vaccines can be diminished by an increase in disease caused by non-vaccine serotypes. To describe pneumococcal serotype epidemiology in Botswana following introduction of 13-valent pneumococcal conjugate vaccine (PCV-13) in July 2012, we performed molecular serotyping of 268 pneumococcal strains isolated from 221 children between 2012 and 2017. The median (interquartile range) age of the children included in this analysis was 6 (3,12) months. Fifty-nine percent of the children had received at least one dose of PCV-13 and 35% were fully vaccinated with PCV-13. While colonization by vaccine serotypes steadily declined following PCV-13 introduction, 25% of strains isolated more than 3 years after vaccine introduction were PCV-13 serotypes. We also observed an increase in colonization by non-vaccine serotypes 21 and 23B, which have been associated with invasive pneumococcal disease and antibiotic resistance in other settings.

POSB314 Method of Predicting Serotype Specific Effectiveness Against Invasive Pneumococcal Disease for Pneumococcal Conjugate Vaccines in Infant Population

Pneumococcal conjugate vaccines (PCVs) have been on the market since the approval of the seven-valent PCV (PCV7) in 2000. PCV7 was subsequently replaced by higher valency vaccines. Higher valency vaccines provide broader serotype coverage against pneumococcal disease, but breakthrough invasive pneumococcal disease (IPD) has been observed [Balsells 2017, Kandasamy 2020] after PCV7 was replaced by PCV13. Furthermore, in clinical trials serotype-specific IgG geometric mean concentrations (GMCs) decreased from PCV7 to PCV13 for shared serotypes, which may contribute to decreased effectiveness observed after the introduction of PCV13 for shared serotypes.

Impact of 7-valent versus 10-valent pneumococcal conjugate vaccines on primary care consultations across various age groups in the Netherlands, 5 years after the switch: A time-series analysis

BackgroundIn 2011, 10-valent pneumococcal conjugate vaccine (PCV10) replaced PCV7 in The Netherlands. We aimed to assess the impact of this switch on non-invasive pneumococcal disease in primary care across various age-groups, including pneumonia-bronchitis, otitis media (OM) and sinusitis with and without considering pre-PCV10 secular trends. MethodsElectronic records of 397,441 individuals included in a regional primary care database from July 2006 to June 2016 were extracted (2,408,762 person-years). We fitted interrupted time-series on annual incidence rates (IR) of primary care diagnosed pneumonia-bronchitis, OM and sinusitis episodes per age-group. We performed these two types of analyses, comparing; 1) the post-PCV10 observed versus expected trend if PCV10 had not been implemented and pre-PCV10 secular trends had continued 2), the pre- versus post-PCV10 observed, model fitted trend. The latter assumes no secular trend. Incidence rate ratios (IRR) were calculated using both methods. ResultsWe found significant reductions following PCV10 introduction with both analysis methods for pneumonia-bronchitis in the pediatric and adult age-groups, for sinusitis in the age-group 20–50 years and for OM, the effect across various age-groups are uncertain given contradictory results. For other outcomes and age-groups, the effect estimates were not consistent across the two-method used and heavily depended on the strength of the underlying trend. No consistent effects were observed in the elderly population, considering the two methods used. ConclusionOur study supports some direct and indirect-effect of PCV10 introduction on non-IPD, mainly on pneumonia-bronchitis, but estimates heavily depend on the method of analysis used. Estimates from the two different approaches may differ substantially if underlying trends are strong.

Pneumococcal conjugate vaccines reduce myringotomy with tympanostomy tube insertion in young children in Japan.

ObjectivePneumococcal conjugate vaccines (PCVs) have been reported to reduce the incidence of myringotomy with tympanostomy tube insertion (MTTI) in children. However, little information is available focusing specific ages. We examined the prophylactic efficacy of PCVs on the onset of complex otitis media (ComOM) that requires MTTI.MethodFrom 2011, the public support for PCV7 started with the usual four‐dose schedule and an emergency schedule for 2‐ to 4‐year‐old children in Japan. PCV7 was replaced with PCV13 in 2013. We reviewed the nationwide database obtained from the JMDC Claims Database (https://www.jmdc.co.jp/en/) to examine the MTTI incidence during the era before and after PCV introduction (from 2008 to 2010 and from 2011 to 2017, respectively). Subjects were analyzed by stratified age groups (from 0 to 8 years old) and in subdivided groups of 6 months (from 0 to 35 months old). We compared the MTTI incidence between the groups for each age as well as between those for each calendar year.ResultsA significant reduction in the MTTI incidence was detected in the 1‐year‐old children of the PCV era compared to those of the pre‐PCV era. The reduction rates were more prominent in the 12–17 months group as compared to the 18–23 months group (PCV7 p = .005 and PCV13 p = .011, PCV7 p = .014 and PCV13 p = .153, respectively). The significant difference in the 1‐year‐old children continued in six of seven calendar years from 2011 to 2017, whereas no significant reduction was detected in children >3 years old.ConclusionsThe introduction of both PCV7 and PCV13 reduced MTTI incidences in children around 1 year old, and the effects were more prominent during the early half‐periods. Our results support etiological evidence that pneumococcal infection in children aged 1 year and younger might play roles in the pathogenesis of ComOM that requires MTTI.

Serotypes and Clonal Composition of Streptococcus pneumoniae Isolates Causing IPD in Children and Adults in Catalonia before 2013 to 2015 and after 2017 to 2019 Systematic Introduction of PCV13.

ABSTRACTThe goal of this study was to investigate the distribution of serotypes and clonal composition of Streptococcus pneumoniae isolates causing invasive pneumococcal disease (IPD) in Catalonia, before and after systematic introduction of PCV13. Pneumococcal strains isolated from normally sterile sites obtained from patients of all ages with IPD received between 2013 and 2019 from 25 health centers of Catalonia were included. Two study periods were defined: presystematic vaccination period (2013 and 2015) and systematic vaccination period (SVP) (2017 to 2019). A total of 2,303 isolates were analyzed. In the SVP, there was a significant decrease in the incidence of IPD cases in children 5 to 17 years old (relative risk [RR] 0.61; 95% confidence interval [CI] 0.38 to 0.99), while there was a significant increase in the incidence of IPD cases in 18- to 64-year-old adults (RR 1.33; 95% CI 1.16 to 1.52) and adults over 65 years old (RR 1.23; 95% CI 1.09 to 1.38). Serotype 8 was the major emerging serotype in all age groups except in 5- to 17-year-old children. In children younger than 5 years old, the main serotypes in SVP were 24F, 15A, and 3, while in adults older than 65 years they were serotypes 3, 8, and 12F. A significant decrease in the proportions of clonal complexes CC156, CC191, and ST306 and an increase in those of CC180, CC53, and CC404 were observed. A steady decrease in the incidence of IPD caused by PCV13 serotypes indicates the importance and impact of systematic vaccination. The increase of non-PCV13 serotypes highlights the need to expand serotype coverage in future vaccines and rethink vaccination programs for older adults.IMPORTANCE We found that with the incorporation of the PCV13 vaccine, the numbers of IPD cases caused by serotypes included in this vaccine decreased in all of the age groups. Still, there was an unforeseen increase of the serotypes not included in this vaccine causing IPD, especially in the >65-year-old group. Moreover, a significant increase of serotype 3 included in the vaccine has been observed; this event has been reported by other researchers. These facts call for the incorporation of more serotypes in future vaccines and a more thorough surveillance of the dynamics of this microorganism.

1180. Comparing Changes in Pneumococcal Meningitis Incidence to all Invasive Pneumococcal Disease Following Introduction of PCV10 and PCV13: The PSERENADE Project

BackgroundThe introduction of higher valency pneumococcal conjugate vaccines (PCV10 and PCV13) has reduced invasive pneumococcal disease (IPD) incidence. It is unknown whether the degree of reduction differs for pneumococcal meningitis, a small subset of pneumococcal disease but a major cause of severe childhood morbidity and mortality globally. We compared the impact of PCV10/13 on pneumococcal meningitis and all IPD by estimating the changes in incidence following the introduction of PCV10/13 among children < 5 years of age.MethodsData on confirmed positive cases for pneumococcus in cerebrospinal fluid (CSF) were obtained directly from surveillance sites. PCV10/13 impact on all-serotype pneumococcal meningitis and all IPD were estimated using site-specific incidence rate ratios (IRRs) at each post-PCV10/13 year relative to the pre-PCV period, using Bayesian multi-level, mixed effects Poisson regression. All-site weighted average IRRs were estimated using linear mixed-effects regression. Results were stratified by product (PCV10 vs. PCV13) and amount of prior PCV7 use (none; some (1-3 years or 4-5 years with < 70% uptake); or many (≥ 4 years with ≥ 70% uptake).Results40 surveillance sites (9 PCV10, 31 PCV13) in 28 countries, primarily high-income (82%) that had both CSF and IPD data were included in analyses. CSF+ accounted for 9.0% of IPD cases (IQR across sites: 6.2%-15.6%). The rate and amount of decline was generally similar between meningitis and IPD across all strata. At 5 years after PCV10/13 introduction, the IRRs across PCV7-use strata were 0.28-0.32 for pneumococcal meningitis and 0.22-0.43 for all IPD at PCV10-using sites, and 0.27-0.41 and 0.21-0.32, respectively, for PCV13-using sites. Only one site from the African meningitis belt contributed eligible data, which lacked pre-PCV data to estimate IRRs, but incidence rate of both IPD and meningitis decreased following PCV introduction. Figure 1. All-Site Weighted Average Incidence Rate Ratios, Children < 5 years * Total sites indicate the number of sites with incidence rate data included and pre/post sites indicate the number of sites with both pre− and post−PCV data to estimate site−specific IRRs for each outcome. The size of point estimates is relative to the number of sites with both pre− and post− data. ** Year 0 indicates the year of PCV10/13 introduction and year −1 indicates the last year of PCV7 use prior to PCV10/13 introduction.ConclusionNet declines in all-serotype IPD and CSF+ meningitis in children < 5 years were similar on average for both PCV10 and PCV13. Data from low-income, high-burden, and meningitis-belt regions were limited. Disclosures Maria Deloria Knoll, PhD, Merck (Research Grant or Support)Pfizer (Research Grant or Support)