Epidemiology Of Invasive Pneumococcal Disease Research Articles

Invasive Pneumococcal Disease in People with HIV in England, 1999-2017

Background: The 7-valent and 13-valent pneumococcal conjugate vaccines (PCVs) were introduced into the United Kingdom childhood immunisation programme in 2006 and 2010 respectively, with high effectiveness and resulting in both direct and indirect protection. We describe the epidemiology of invasive pneumococcal disease (IPD) in adults with HIV in England following the introduction of both PCVs. Methods: Data on a national cohort of people with HIV were linked to confirmed IPD cases in adults aged ≥15 years during 1999-2017. Date of HIV infection was estimated using a CD4 slope decline algorithm. Findings: Among 133,994 adults with HIV, 1,453 developed IPD during 1999-2017, with 70% (1,016/1,453) developing IPD ≥3 months after their HIV diagnosis. IPD and HIV were co-diagnosed within 90 days in 345 (24%) individuals. A missed opportunity for earlier HIV diagnosis was identified in 6% (89/1,453), mostly in earlier years. IPD incidence in people with HIV increased from 147/100,000 in 1999 to 284/100,000 in 2007 before declining and stabilising between 92-113/100,000 during 2014-2017. Mean annual IPD incidence was lower among those receiving ART during 2014-17 (720 vs. 68/100,000; IRR 9.3; 95%CI, 7.3-11.8; P<0.001) and was markedly lower in those with a suppressed viral load (523 vs. 50/100,000; IRR 10.4; 95%CI, 7.6-14.1; P<0.001). The latter group still had 4.5-fold higher (95%CI, 3.8-5.3; P<0.001) IPD incidence compared to the general population (11.2/100,000). Interpretation: IPD incidence among people with HIV reduced after PCV13 introduction and has remained stable. Adults presenting with IPD should continue to be tested for HIV infection. Funding Statement: The authors are employed by PHE. There was no additional funding for this study. Declaration of Interests: PDK, ZAC, SEC, CS, NF and VCD declare no conflicts of interest. SNL performs contract research on behalf of St. George’s University of London (SGUL) and Public Health England (PHE) for vaccine manufacturers but receives no personal remuneration. The Immunisation Department has provided vaccine manufacturers with post-marketing surveillance reports on pneumococcal and meningococcal infection which the companies are required to submit to the UK Licensing authority in compliance with their Risk Management Strategy. A cost recovery charge is made for these reports. Ethics Approval Statement: PHE has legal permission, provided by Regulation 3 of The Health Service (Control of Patient Information) Regulations 2002, to process patient confidential information for national surveillance of communicable diseases (http://www.legislation.gov.uk/uksi/2002/1438/regulation/3/made). This includes PHE’s responsibility to monitor the safety and effectiveness of vaccines.

Effect of childhood pneumococcal conjugate vaccination on invasive disease in older adults of 10 European countries: implications for adult vaccination

BackgroundPneumococcal conjugate vaccines (PCVs) have the potential to prevent pneumococcal disease through direct and indirect protection. This multicentre European study estimated the indirect effects of 5-year childhood PCV10 and/or PCV13...

Invasive pneumococcal disease and serotype emergence in the Auckland region during the vaccine era 2009-16.

INTRODUCTION There is a deficit of knowledge in New Zealand as the epidemiology of invasive pneumococcal disease varies significantly between countries. AIM Time trends and sociodemographic characteristics of cases of invasive pneumococcal disease (IPD) in the Auckland region are reviewed after the introduction of a conjugate vaccination, to provide evidence for future vaccine policy and to ensure Auckland region analysis is representative of national trends for subsequent IPD analysis. METHODS Data on all cases of IPD occurring in Waitemata, Auckland and Counties Manukau District Health Boards between 2009 and 2016 were extracted from EpiSurv. Denominator data were drawn from mid-year estimates supplied by Statistics New Zealand. Descriptive epidemiology and time-series regression was performed to analyse trends. RESULTS Rates of IPD have fallen in the Auckland region over the past 8 years by 32%. While absolute rates in the elderly have reduced by 12%, they have the highest disease burden at 32/100,000. The ethnic disparity continues with Pacific people (33/100,000) and Māori (14/100,000) over represented compared to European (10/100,000). In the elderly, the 19A serotype has increased from an incidence of 0 in 2008 to 8.2/100,000. DISCUSSION Large ethnic and age-related disparities are observed in the Auckland region, consistent with the rest of the country, since the start of the pneumococcal vaccination era. Extending immunisation to the elderly may help close these gaps. As with other countries, there is 19A serotype replacement occurring following conjugate vaccine introduction.

Epidemiology of Invasive Pneumococcal Disease in the Kingdom of Saudi Arabia – A Rapid Review of the Literature

Epidemiology of Invasive Pneumococcal Disease in the Kingdom of Saudi Arabia – A Rapid Review of the Literature

Epidemiology of invasive pneumococcal disease in the city of Kenora, Ontario, Canada, and surrounding area (2010-2016)

Introduction: Streptococcus pneumoniae is a recognized important pathogen in Indigenous populations in the Sioux Lookout area of Northwestern Ontario, Canada. This study investigates the current epidemiology of invasive pneumococcal disease (IPD) in the Kenora area of Northwestern Ontario, which has a relatively large Indigenous population (30%). Methods: Data from January 2010 to December 2016 were retrieved from retrospective chart review at a hospital servicing a population of 19,380. Results: Thirty-one cases of IPD were identified. Regional incidence (26.6/100,000/year) is nearly three times the national rate (9.0/100,000/year). In adults, 66.7% of cases were caused by serotypes included in the 23-valent pneumococcal polysaccharide vaccine. All pediatric IPD cases were caused by serotypes not included in the 13-valent pneumococcal conjugate vaccine. Ninety per cent of cases had confirmed underlying disease. Conclusions: In the Kenora area, IPD incidence is comparable to incidence in the Sioux Lookout area. Improvement of pneumococcal vaccination uptake in senior and high-risk populations is required.

Epidemiology of invasive pneumococcal disease in indigenous and non-indigenous adults in northwestern Ontario, Canada, 2006\u20132015

BackgroundDespite the use of pneumococcal vaccines, indigenous populations are consistently disproportionately affected by invasive pneumococcal disease (IPD). With recent changes in Ontario’s provincial pneumococcal vaccination program, we sought to evaluate the epidemiology and burden of IPD in northwestern Ontario (NWO) Canada – a region that contains a substantial (19.2%) indigenous population.MethodsWe retrospectively reviewed all adult cases of IPD that were reported to the Thunder Bay District Health Unit, in Thunder Bay, Ontario, Canada, over a 10-year period (2006–2015). Patients admitted to the Thunder Bay Regional Health Sciences Centre with IPD had their charts reviewed to abstract clinical data. Statistical analysis, including incidence rates of IPD, was performed.ResultsTwo hundred sixty-two cases of IPD occurred over the 10-year observation period and clinical data was available for 182 cases. Fifty-three of 182 (29.1%) patients were indigenous. 73 of 182 (40.1%) of patients were immunocompromised. Indigenous patients with IPD were more likely to be immunocompromised than non-indigenous patients (p < 0.001). Serotype data was available for 159 cases of IPD; PCV7, PCV13, and PPV23 covered 5.7%, 28.3%, and 79.2% of isolates, respectively, while 29 (20.8%) were non-vaccine serotypes. The annual incidence rate of IPD ranged from 8.9 to 25.9 per 100,000 among adults 18–64 years old; among adults 65 years of age and older the annual incidence of IPD ranged from 18.5 to 60.7 per 100,000.ConclusionAmong adults in NWO, Canada, there is a high incidence of IPD. Immunocompromised indigenous adults in NWO may benefit from pneumococcal vaccination coverage. Emerging non-vaccine serotypes of Streptococcus pneumoniae warrant the consideration of the provincial pneumococcal vaccination program.

Spatial Distribution of Invasive Pneumococcal Serotypes in West Africa: A Retrospective Analysis to Inform Immunization in Persons with Sickle Cell Disease

Background: Susceptibility to invasive pneumococcal disease (IPD) is high in children with sickle cell disease (SCD). National guidelines in many countries recommend a combined schedule of 13-valent pneumococcal conjugate vaccine (PCV13) beginning after birth followed by the 23-valent polysaccharide vaccine (PPSV23) beginning at age 2 years. In Africa, where the burden of SCD is greatest, PPSV23 is generally unavailable and not routinely administered to children with SCD. To help inform optimal immunization regimens for children with SCD in West Africa, we sought to determine the prevalence and spatial distribution of IPD in the region. We focused specifically on the 24 combined pneumococcus strains covered by PCV13 (serotypes 1, 3, 4, 5, 6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, and 23F) and PPSV23 (serotypes 1, 2, 3, 4, 5, 6B, 7F, 8, 9N, 9V, 10A, 11A, 12F, 14, 15B, 17F, 18C, 19A, 19F, 20, 22F, 23F, and 33F). This analysis also explored the epidemiology of IPD-associated serotypes after the introduction of routine PCV13 immunization in countries in West Africa.Methods: We conducted a systematic review of published literature between 1990 and January 2017 using BIOSIS Previews, Embase, and Ovid MEDLINE. Inclusion criteria were all investigations that reported estimates of prevalence or incidence and the specific serotype distribution profile of invasive Streptococcus pneumoniae (including bacteremia, meningitis, osteomyelitis, or pneumonia) in children and adults in ECOWAS-defined West Africa: Benin, Burkina Faso, Cape Verde, Cote d'Ivoire, Gambia, Ghana, Guinea, Guinea-Bissau, Liberia, Mali, Niger, Nigeria, Senegal, Sierra Leone, and Togo. The search strategy utilized various combinations of relevant keywords and MeSH headings. Timing of the introduction of routine PCV13 immunization into study countries was determined through WHO national immunization coverage surveillance data. We generated maps of the spatial distribution of pneumococcal serotypes in countries with available data using R (version 3.3.3).Results: The search yielded 540 unique studies. We excluded 395 papers based on title and abstract. The remaining 145 studies underwent full text review. Twenty papers (representing 20 datasets and 1980 isolates) met inclusion criteria. Gambia had the most datasets (5); no data were available from six countries (Benin, Cape Verde, Cote d'Ivoire, Guinea, Liberia, and Sierra Leone); and at least one dataset was available from each of the remaining 8 countries. The most frequent invasive serotypes reported across countries were 1, 5, 6A, 12F, 14, and 23F; together, these represented 79.7% of all serotypes identified in IPD in children and adults in West Africa. Most (89.2%) of the serotypes identified are included in PCV13. However, serotypes 2 and 12F, which are covered only by PPSV23, represented 3.3% and 4.8% of identified IPD serotypes, respectively, across the 9 countries studied. These serotypes also accounted for up to 10% of isolates found in individual countries. PCV13 was introduced into all countries with datasets analyzed between 2011 and 2015. Only 1 dataset identified in the literature search (Ghana) was obtained after the introduction of routine pneumococcal vaccination, which precluded analysis of the impact of vaccination on temporal trends in serotype incidence.Conclusions: To our knowledge this is the first attempt to aggregate IPD serotype data across West Africa. While the majority of serotypes identified are included in PCV13, two serotypes exclusive to PPSV23 (2 and 12F) together accounted for 8.1% of the total IPD burden. Moreover, in some countries, the proportion of strains included in PPSV23 and not PCV13 is higher. Immunizing persons with SCD in West Africa with PPSV23 therefore may be warranted to optimize protection from IPD. Furthermore, as PCV13 vaccination coverage increases, it is possible that the epidemiology of IPD may shift to more strains exclusively covered by PPSV23. This analysis is limited by its retrospective nature and the paucity of data available after introduction of routine pneumococcal vaccination. Further work, including dynamic IPD surveillance and disease modeling, is needed to better understand the epidemiology of pneumococcus in West Africa with the aim of keeping vulnerable populations, such as those with SCD, safe from IPD. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

1430. Evolving Impact of 13-Valent Pneumococcal Conjugate Vaccine on Invasive Pneumococcal Disease

BackgroundThe 13-valent pneumococcal conjugate vaccine (PCV13) replaced PCV7 in the childhood immunization schedule in Massachusetts (MA) beginning in April, 2010. We describe the current epidemiology of invasive pneumococcal disease (IPD) in Massachusetts (MA) children after introduction of PCV13.MethodsCases of invasive pneumococcal disease (IPD) in children <18 years of age were detected through an enhanced surveillance system in MA since 2001. All cases in children and Streptococcus pneumoniae (SP) isolates, when available, are submitted to Department of Public Health (MDPH) and parents/physicians are interviewed for confirmation of demographic and clinical data. All available isolates are confirmed as SP, serotyped by Quellung reaction.ResultsThere were 351 IPD cases in MA children from April 1, 2010 to September 31, 2017, and 36 (10.3%) were in infants <6 months; 42 (12.0%) in children between 6 and 12 months; 63 (18.0%) in toddlers 12–24 months; 102 (29.1%) in children aged 2–5 years, and 108 (30.8%) were in children aged ≥5 years. Incidence of IPD declined to 6.8/105 children (95% CI 2.6–11.1) in 2015/2016 period which represents a 72.1% decline compared with 2010/2011 (24.4/105, 95% CI 16.3–32.5) (figure). However, in 2016/2017, IPD incidence increased to 10.4/105 children (95% CI 5.2–15.7). The most common clinical presentation was bacteremia (62.9%), followed by pneumonia (30.5%) and CNS disease (6.6%). Among, 103 (32.6%) children with ≥1 comorbidity, asthma (13.2%), hematologic malignancy (12.1%), prematurity (9.9%) and sickle cell disease (9.9%) were the most common comorbidities. He overall mortality rate was 5.1%. Isolates from 308 (89.3%) were available for serotyping; vaccine serotypes (VST) were identified in 106 (33.3%) IPD cases [19A (46.2%), 7F (19.9%), 3 (17.9%), 19F (10.4%), 6A (2.8%), 14, 18C, 5 (0.9% each). Serotypes 15BC (13.7%), 22F (12.6%) and 33F (11.8%) were the most common nonvaccine serotypes (NVST).ConclusionInvasive pneumococcal disease identified in the post-PCV13-era is primarily caused by NVSTs, specifically serotypes 15BC, 33F and 22F; and disproportionately observed in children with comorbid conditions. Continued surveillance is necessary to determine the impact of PCV13, as well as track potential changes in disease incidence and character due to NVST. Disclosures All authors: No reported disclosures.

Serotypes and genotypes of S. pneumoniae isolates from adult invasive disease in Spain: A 5-year prospective surveillance after pediatric PCV13 licensure. The ODIN study

Serotypes/genotypes causing invasive pneumococcal disease (IPD) in adults are determined by vaccination strategies. The aim of this study was to assess the epidemiology of IPD in adults (≥18 years) after PCV13 introduction for children: serotypes, clonal complexes, antibiotic non-susceptibility and clinical presentations.We performed a prospective, clinical surveillance of hospitalized culture-confirmed IPDs in adults in nine Spanish hospitals (August 2010–June 2015). A total of 1087 culture-confirmed IPD episodes were included, of which 772 (71.0%) had bacteremic pneumonia (401 complicated/371 uncomplicated pneumonia), 122 (11.2%) meningitis, 102 (9.4%) non-focal bacteremia, 34 (3.1%) peritonitis and 57 (5.3%) others. The most common serotypes were: 3 (12.7%), 19A (8.5%), 8 (7.7%), 7F (6.3%), 1 (4.2%), 6C (4.2%), 11A (4.2%), 22F (4.2%) and 14 (4.0%). Vaccine types (PCV13 + 6C) caused 49.8% of IPD episodes, with a significant decrease over the 5-year period, and significant decreases in serotypes 6C and 7F. The most common genotypes were: CC180 (8.4%), CC191 (6.0%), and CC53 (5.0%).Vaccine types caused 53.9% (414/768) pneumonia episodes and 58.9% (235/399) complicated pneumonia, 53.4% IPD in adults <50 years (143/268), and 54.7% IPD in immunocompetent patients (337/616). Overall non-susceptibility was 25.9% to penicillin (1.1% for parenteral criteria), 24.9% to erythromycin and 2.7% to levofloxacin. ConclusionsAlthough the percentage of vaccine-types causing IPDs in adults significantly decreased, it remained high. Associations of vaccine types with pneumonia (with complicated pneumonia for specific serotypes), and immunocompetent patients point to the burden of IPD caused by PCV13 serotypes.

Limited impact of pneumococcal vaccines on invasive pneumococcal disease in Nunavik (Quebec).

In 2002, a mass immunization campaign using the 23-valent pneumococcal polysaccharide vaccine (PPV23) was carried out in Nunavik to control an outbreak caused by a virulent clone of serotype 1 Streptococcus pneumoniae. At the same time, the 7-valent pneumococcal conjugate vaccine (PCV7) was introduced for routine immunization of infants, replaced by the 10-valent vaccine (PCV10) in 2009, and the 13-valent vaccine (PCV13) in 2011. The objective of this study was to describe the epidemiology of invasive pneumococcal disease (IPD) in relation to pneumococcal vaccine use. Retrospective analysis of IPD cases identified by the Quebec Public Health Laboratory during the period 1997-2016. One hundred thirty-two IPD cases were identified during the study period. In adults, serotype 1 incidence decreased following the 2002 PPV23 mass campaign, but breakthrough cases occurred. Following PCV use, the incidence of vaccine-type IPD decreased markedly in children and also in adults but serotypes not covered by conjugate vaccines increased. The overall IPD rate was 43/100,000 person-years in the 1997-1999 pre-vaccine era and 58/100,000 person-years in 2010-2016. The 2002 PPV23 mass immunization campaign may have contributed to control the serotype 1 outbreaks in Nunavik, but its effect was short-lived as IPDs caused by serotypes included in this vaccine continued to occur after 2005. PCV use in children induced important modifications in the epidemiology of IPD, but most of thebenefits were eroded by serotype replacement.

Indirect Effects of Pneumococcal Childhood Vaccination in Individuals Treated With Immunosuppressive Drugs in Ambulatory Care: A Case-cohort Study.

The extent to which iatrogenically-immunosuppressed individuals benefit from indirect effects of childhood vaccination with pneumococcal conjugate vaccines (PCVs) is unknown. We determined how the sequential introduction of PCV7 (2006) and PCV13 (2011) in the Norwegian childhood vaccination program has affected the epidemiology of invasive pneumococcal disease (IPD) in individuals treated with immunosuppressants in ambulatory care. We conducted a case-cohort study comprising 7926 IPD cases reported to the Norwegian Surveillance System for Communicable Diseases in 2005-2014 and 249998 individuals randomly selected from the National Registry in 2012. We defined immunosuppressive treatment groups based on dispensed prescriptions retrieved from the Norwegian Prescription Database. Incidences and age-adjusted relative risks (RR) were estimated. IPD incidences decreased in all groups. The PCV13 incidence decreased by 5-12% across groups. The non-PCV13 incidence increased by 4-10%, mostly in individuals on chemotherapy (overlapping 95% confidence intervals). In the PCV13 era, the RR for IPD was highest (significant) and the percentage of cases caused by the polysaccharide vaccine PPV23 serotypes lowest (numerical) in individuals on chemotherapy (RR = 20.4, PPV23 = 52%), followed by individuals on corticosteroids (RR = 6.2, PPV23 = 64%), other immunosuppressants (RR = 5.6, PPV23 = 68%), and no immunosuppressants (RR = 1 [reference], PPV23 = 74%). IPD incidences declined after PCV introduction in both immunocompetent and iatrogenically-immunosuppressed individuals, underscoring the benefit of childhood vaccination for the entire population. Still, individuals treated with immunosuppressants in ambulatory care are at increased risk of IPD caused by a more diverse group of serotypes.

The changing epidemiology of invasive pneumococcal disease after PCV13 vaccination in a country with intermediate vaccination coverage

BackgroundWe studied the impact of 13-valent pneumococcal conjugate vaccine (PCV13) on the incidence of invasive pneumococcal disease (IPD) and serotype distribution in a region with intermediate levels of vaccination (around 64% in children aged <2 years). MethodsSurveillance data on IPD cases reported by microbiologists participating in the Microbiological Reporting System of Catalonia during 2006–2014 were analysed. We compared estimated incidence rate (IR) ratios for serotypes included in PCV7, PCV10non7, PCV13non10 and non-PCV13 between the PCV7 (2006–2009) and PCV13 periods (2010–2014). IR were corrected for missing serotypes according to year and age groups: <2 years, 2–4 years, 5–64 years and ≥65 years. ResultsA total of 9338 IPD cases were reported. Overall IPD incidence declined by 26.2% (from 16.4 to 12.1) in the PCV13 period. The largest decrease was observed in children aged 2–4 years (44.5%, from 37.4 to 20.8). Pneumonia fell in all age groups with the largest reduction in children aged 2–4 years (49.3%) and <2 years (42%). PCV13 serotypes decreased significantly in all age groups, from 52% (31.6 to 15.1) in children aged 2–4 years to 35% (22.8 to 14.8) in adults aged ≥65 years. Non-PCV13 serotypes rose by 13% (14.8 to 16.8) in people aged ≥65 years. ConclusionsIn a region with intermediate vaccination coverage, the introduction of PCV13 has reduced the overall incidence of IPD, mainly due to the decrease in PCV13 serotypes in all age groups, suggesting herd immunity. Non-PCV13 serotypes have increased in adults aged ≥65 years, suggesting serotype replacement. Higher PCV13 vaccination coverage in children will further reduce IPD incidence in all age groups.

Serotype distribution of invasive Streptococcus pneumoniae in adults 65 years of age and over after the introduction of childhood 13-valent pneumococcal conjugate vaccination programs in Canada, 2010–2016

The 13-valent conjugate vaccine (PCV13) was recommended for childhood immunization programs in 2010 in Canada and has decreased the incidence of invasive pneumococcal disease (IPD) in children and changed the epidemiology of IPD in adults. This study investigated the epidemiology of IPD in adults 65 years of age and older in Canada. A total of 7282 invasive S. pneumoniae isolated from adults ≥65 years old were serotyped from 2010 to 2016 and antimicrobial susceptibility was performed on 2527 isolates. Serotyping was performed by Quellung reaction using commercial antisera and antimicrobial susceptibilities were determined by broth microdilution. PCV7 serotypes decreased non-significantly from 2010 to 2016 from 9.1% (n = 96) to 6.7% (n = 72) while the additional six PCV13 serotypes declined significantly from 39.5% (n = 418) to 18.6% (n = 201) (p < 0.05). The 23-valent pneumococcal polysaccharide vaccine (PPV23) and non-vaccine (NVT) serotypes increased from 26.3% (n = 278) to 36.2% (n = 393) (p < 0.05), and from 25.1% (n = 266) to 38.4% (n = 416) (p < 0.05), respectively. There were no significant changes in antimicrobial resistance rates from 2011 to 2016: 24.1% of the IPD from adults ≥65 years were resistant to clarithromycin (n = 609), 10.0% to doxycycline (n = 254), 11.8% to penicillin (n = 299), 5.2% to cefuroxime (n = 131), 6.6% to clindamycin (n = 168), 6.0% to trimethoprim-sulfamethoxazole (n = 152), and 0.5% (n = 12) to ceftriaxone. Although overall incidence of IPD in adults ≥65 years has remained relatively constant from 2010 to 2016, childhood PCV13 vaccination programs have been successful in indirectly reducing IPD caused by PCV13 serotypes in adults through herd immunity effects.

Invasive pneumococcal disease in Indian adults: 11 years' experience.

To investigate the epidemiology of invasive pneumococcal disease (IPD), prevalent serotypes, and pattern of antimicrobial resistance (AMR) in Indian adults. Prospective laboratory based surveillance of IPD was carried out in >18 years age group between January 2007 and July 2017, from a tertiary care hospital in South India. All Streptococcus pneumoniae culture positives from blood, CSF and sterile body fluids were characterized to identify the serotypes and AMR. A total of 408 IPD cases were characterized in this study. The overall case fatality rate in this study was 17.8% (95% confidence interval (CI): 14.1, 22.4). Pneumonia (39%), meningitis (24.3%), and septicaemia (18.4%) were the most common clinical conditions associated with IPD. Serotypes 1, 3, 5, 19F, 8, 14, 23F, 4, 19A and 6B were the predominant serotypes in this study. Penicillin non-susceptibility was low with 6.4% CONCLUSION: Serotype data from this study helped in accurate estimation of pneumococcal conjugate vaccine-13 and pneumococcal polysaccharide vaccine-23 protective coverage against serotypes causing IPD in India as 58.7% (95% CI: 53.8, 63.4) and 67.4% (95% CI: 62.7, 71.8) respectively. Penicillin non-susceptibility in meningeal IPD cases is 27.4%. Empirical therapy for meningeal IPD must be cephalosporin in combination with vancomycin since cefotaxime non-susceptibility in meningeal IPD is 9.9.

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.

Changing Epidemiology of Invasive Pneumococcal Disease due to Conjugate Vaccine Serotypes in Toronto, Canada After Introduction of a Routine Pediatric PCV13 Program

BackgroundIn Ontario a publicly funded PCV7 infant program (3 + 1 schedule), was introduced in 1/2005, PCV10 in 10/2009 and PCV13 in 11/2010 (2 + 1 schedule with catch-up to 35m). TIBDN performs population-based surveillance for invasive pneumococcal disease (IPD) in Toronto/Peel to evaluate program impact.MethodsIPD cases are reported to a central office and one isolate/case is serotyped. Demographic/ clinical data are collected by chart review and patient/physician interview.ResultsFrom 1/1995–5/2017, 9727 IPD cases have been identified. Among 910 IPD cases since 2015, 109 (12%) were aged <15y, 376 (41%) 15–64y and 425 (41%) aged ≥65y; 57 (7%) were due to serotypes (STs) included in PCV7, 188 (24%) due to STs in PCV13 but not PCV7, 228 (30%) due to STs in PPV23 but not PCVs, and 295 (38%) due to non-vaccine STs (142 isolates not available/not yet typed). The incidence of IPD in 2016 was 4.78/100000 in children and 5.68/100000 in adults (44% and 32% reduction since 2008/9 respectively.Since 1/1/2015, there has been no IPD due to PCV7 STs in children. In adults, 57 episodes include 19 of ST4, 13 ST19F, 8 ST14, 7 ST6B, 5 ST9V, 3ST18C and 2 ST23F. The median age of patients was 64.5y (range 28–98), 37 were male; 67% had an underlying illness. PCV7 ST cases were more likely to be associated with group housing than other cases (12/45, 21%, v 47/644, 7%, P < .01); 6/19 cases of ST4 were associated with a single homeless shelter, and 3/8 due to ST14 occurred in one nursing home.Of 188 episodes due to PCV13/not PCV7 serotypes, 87 were due to ST3, 72 ST19A, 16 ST7F, 11 ST6A, and 1 each due to ST1 and ST5. 22 cases occurred in children (12 ST3, 9 ST19A, 1 ST7F): 1 child refused consent, and 1 had missing data; 4 were vaccine ineligible; 2 unvaccinated; 9 incompletely vaccinated; and 5 vaccine failures (2 ST3, 3 ST19A). The most recent case of pediatric IPD due to ST19A was in Aug/2016; both pediatric cases to date in 2017 are ST3. The incidence of IPD due to STs 19A and 3 over time in children and adults is shown in the Figures.ConclusionSince PCV13-program implementation, IPD due to PCV7 STs has decreased to zero among children and remains low in adults, although clusters in communal living situations may be emerging. IPD due to ST19A has declined dramatically. IPD incidence due to ST3 has not changed significantly since 1995.Disclosures All authors: No reported disclosures.

The epidemiology of invasive pneumococcal disease in older adults in the post-PCV era. Has there been a herd effect?

The 7 and 13-valent pneumococcal conjugate vaccines (PCVs) have reduced the incidence of invasive pneumococcal disease (IPD) in children in many countries. The objective of this work was to assess the impact of PCVs and potential herd-protection in older adults in Ireland. IPD notification and typing data from adults ⩾65 years of age from July 2007 to June 2016 was assessed using national surveillance data. There was a 94% reduction in PCV7 serotypes from 2007-2008 to 2015-2016, incidence rate ratio (IRR 0·05, P < 0·0001). However, there was no decline in the additional PCV13 (PCV13-7) serotypes over the same period (IRR 0·90) nor in comparison with the pre-PCV13 period 2009-2010 (IRR 0·92). The incidence of serotypes in the 23-valent pneumococcal polysaccharide vaccine only (PPV23-PCV13) and non-vaccine types (NVTs) increased significantly (IRR 2·17, P = 0·0002 and IRR 3·43, P = 0·0001 respectively). Consequently, the overall IPD incidence rate in adults has remained relatively unchanged (from 28·66/100 000 to 28·88/100 000, IRR 1·01, P = 0·9477). Serotype 19A and NVTs were mainly responsible for penicillin resistance in recent years. The decline of PCV7 serotypes indicate that the introduction of PCV7 resulted in herd-protection for adults. However, increases in PPV23-PCV13 and NVTs suggest that changes in vaccination strategy amongst older adults are needed to build on the success of PCVs in children.

The Changing Epidemiology of Invasive Pneumococcal Disease Among the Indigenous and Non-indigenous Population of Northwestern Ontario, Canada, from 2006 Through 2015 and Emergence of Non-vaccine Serotypes

BackgroundRates of invasive pneumococcal disease (IPD) among indigenous populations remain substantially higher than their non-indigenous counterparts. The goal of this study was to analyze the epidemiology and demographic features of IPD in northwestern Ontario (NWO) among the indigenous and non-indigenous population in the context of recent changes in the provincial pneumococcal vaccination programs.MethodsTwo databases were used to identify cases of IPD in NWO: Thunder Bay Regional Health Sciences Centre and the Thunder Bay District Health Unit. Adult patients with a diagnosis of IPD at the TBRHSC from January 1, 2006 to December 31, 2015 had their medical charts retrospectively reviewed; TBDHU data contained only serotype, age, and gender data.ResultsTable 1.Number of IPD cases and case fatality rate by indigenous status at the TBRHSC, 2006–2015# of cases# of deathsyearindigenousnon-indigenoustotalindigenousnon-indigenoustotal2006371000020070880112008511160112009820282022010517220222011622281122012381101120131012221342014101121000201531316022total531291824111553 of 182 (29.0%) of patients were indigenous. 35 of 53 (66.0%) of indigenous patients were immunocompromised, whereas 38 of 129 (29.5%) of non-indigenous patients were immunocompromised and the difference was statistically significant (P < 0.001, by chi square test). 35 of 73 (48.0%) of immunocompromised patients were indigenous.Table 2.Serotype distribution of Streptococcus pneumoniae causing IPD in northwestern Ontario, Canada, 2006–2015 (includes both TBRHSC + TBDHU data).yearPCV7PCV13PCV23non-vaccine serotypesunknown serotypestotal200600002626200710211216200822541427200931293164320100784123120112101249372012021184252013032128342014129382320151076923total10388435118285The proportion of non-vaccine serotypes has increased, on average, by 16% per year (P = 0.024, 95% CI: 1.02, 1.32).ConclusionHigh rates of IPD were found to occur among immunocompromised indigenous adults in NWO. Our findings identify a vulnerable cohort of the population that would benefit from pneumococcal vaccination coverage. The proportion of non-vaccine serotypes causing IPD has increased during the 10-year observation period.Disclosures M. Ulanova, Pfizer: Grant Investigator, Grant recipient

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 children immunization according to a 2 + 1 doses schedule.Objective: To assess the impact of this program on the epidemiology of invasive pneumococcal disease (IPD).MethodsNotification (2000–2016) and laboratory surveillance (2005–2016) data were analyzed and the immunization status of IPD cases in 2011–2015 was checked.ResultsIn children <5 years, IPD rate decreased from 69/100,000 in 2003 to 12/100,000 in 2016 (83% reduction). Following PCV7 introduction in 2004, there was a rapid decline in incidence of homologous serotypes. 7F cases and 19A decreased following PCV10 introduction in 2009 and PCV13 in 2011, whereas decrease in serotype 3 IPD was minimal. Non-vaccine types IPD 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 covered by the 23-valent polysaccharide vaccine. Out of 7 IPD cases caused by serotype 3 in children vaccinated with PCV13, 5 occurred more than one year following the booster dose, which suggests short-term protection. Out of 27 breakthrough 19A cases, 17 occurred between 8 and 14 months of age in children 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.ConclusionHopefully, 19A incidence in children will continue to decrease and herd protection would eventually close the window of susceptibility. Serotype 3 is fortunately not frequent in children but a hard nut to crack. In elderly adults, PCV13 serotype coverage is diminishing year after year but a majority of cases remains potentially covered by the 23-valent polysaccharide vaccine.Disclosures P. De Wals, GSK: Investigator and Scientific Advisor, Research grant and Travel expenses; Pfizer: Grant Investigator and Scientific Advisor, Research grant and Travel expenses; SanofiPasteur: Grant Investigator, Research grant and Travel expenses

The epidemiology of invasive pneumococcal disease in older adults from 2007 to 2014 in Ontario, Canada: a population-based study.

In Ontario, pneumococcal conjugate vaccines (PCVs) have been sequentially introduced into the publicly funded childhood vaccination program since 2005. A 23-valent polysaccharide pneumococcal vaccine (PPV23) has been routinely recommended for adults aged 65 years and older since 1996. To determine the effect of herd immunity, we examined the epidemiology of invasive pneumococcal disease in adults aged 65 years and older. Invasive pneumococcal disease is a provincially reportable disease. We were therefore able to conduct a descriptive epidemiologic analysis that included assessing time trends for patients aged 65 years and older using surveillance data from 2007 to 2014. Using serotype information within the surveillance data, cases were grouped into categories according to vaccine type and periods and then compared using Poisson regression. A total of 3825 cases of invasive pneumococcal disease were reported among adults aged 65 years and older, for an overall annualized incidence of 25.4 cases per 100 000 population. There was a decrease in incidence due to serotypes included in 7-valent PCV (3.0 to 0.7 cases per 100 000 population) (p < 0.001). For 13-valent PCV serotypes, there was a decrease in incidence between 2011 and 2014 (9.8 to 5.3 cases per 100 000 population (p < 0.001)). Serotypes unique to PPV23 and those not included in a vaccine increased from 2.3 to 5.8 and from 2.4 to 7.2 cases per 100 000 population, respectively (p < 0.001). In older adults, among serotypes contained in PCVs, we have shown a decrease in incidence of invasive pneumococcal disease. This is likely due to herd immunity from the childhood program. A burden of illness due to unique PPV23 serotypes and those that are not covered by a vaccine exists and has increased over time.