Pneumococci isolated from children in community-based practice differ from isolates identified by population and laboratory-based invasive disease surveillance.

BACKGROUND: Characterizing strains causing noninvasive and invasive pneumococcal disease (IPD) may inform the impact of new pneumococcal conjugate vaccines (PCVs). METHODS: During 2011-2019, among children aged 6-36 months, pneumococcal serotype distribution and antibiotic non-susceptibility of nasopharyngeal and middle ear fluid (MEF) isolates collected at onset of acute otitis media (AOM) in Rochester, New York were compared with IPD isolates from Active Bacterial Core surveillance (ABCs) across 10 U.S. sites. RESULTS: From Rochester, 400 (nasopharyngeal) and 156 (MEF) pneumococcal isolates were collected from 259 children. From ABCs, 907 sterile-site isolates were collected from 896 children. Non-PCV serotypes 35B and 21 were more frequent among the Rochester AOM cases, while serotypes 3, 19A, 22F, 33F, 10A, and 12F contained in PCVs were more frequent among ABCs IPD cases. The proportion of antibiotic non-susceptible pneumococcal isolates was generally more common among IPD cases. In 2015-2019, serotype 35B emerged as the most common serotype associated with multiclass antibiotic non-susceptibility for both the Rochester AOM and ABCs IPD cases. CONCLUSIONS: Pneumococcal isolates from children in Rochester with AOM differ in serotype distribution and antibiotic susceptibility compared to IPD cases identified through U.S. surveillance. Non-PCV serotype 35B emerged as a common cause of AOM and IPD.

Effect of pneumococcal conjugate vaccines on viral respiratory infections: a systematic literature review.

BACKGROUND: In addition to preventing pneumococcal disease, emerging evidence indicates that pneumococcal conjugate vaccines (PCVs) might indirectly reduce viral respiratory tract infections (RTI) by affecting pneumococcal-viral interactions. METHODS: We performed a systematic review of interventional and observational studies published during 2000-2022 on vaccine efficacy/adjusted effectiveness (VE) and overall effect of PCV7, PCV9, PCV10, or PCV13 against viral RTI. RESULTS: Sixteen of 1671 records identified were included. Thirteen publications described effects of PCVs against viral RTIs in children. VE against influenza ranged between 41-86% (n=4), except for the 2010-2011 influenza season. In a randomized controlled trial, PCV9 displayed efficacy against any viral RTI, human seasonal coronavirus, parainfluenza, and human metapneumovirus. Data in adults were limited (n=3). PCV13 VE ranged between 4-25% against viral lower RTI, 32-35% against COVID-19 outcomes, 24-51% against human seasonal coronavirus, and 13-36% against influenza A lower RTI, with some 95%CI spanning zero. No protection was found against adenovirus or rhinovirus in children or adults. CONCLUSIONS: PCVs were associated with protection against some viral RTI, with the strongest evidence for influenza in children. Limited evidence for adults was generally consistent with pediatric data. Restricting public health evaluations to confirmed pneumococcal outcomes may underestimate the full impact of PCVs.

Effect of Pneumococcal Conjugate Vaccine on Pneumonia Incidence Rates among Children 2-59 Months of Age, Mongolia, 2015-2021.

Starting in June 2016, the 13-valent pneumococcal conjugate vaccine (PCV13) was introduced into the routine immunization program of Mongolia by using a 2+1 dosing schedule, phased by district. We used prospective hospital surveillance to evaluate the vaccine's effect on pneumonia incidence rates among children 2-59 months of age over a 6-year period. Of 17,607 children with pneumonia, overall adjusted incidence rate ratios showed decreased primary endpoint pneumonia, very severe pneumonia, and probable pneumococcal pneumonia until June 2021. Results excluding and including the COVID-19 pandemic period were similar. Pneumonia declined in 3 districts that introduced PCV13 with catch-up campaigns but not in the 1 district that did not. After PCV13 introduction, vaccine-type pneumococcal carriage prevalence decreased by 44% and nonvaccine-type carriage increased by 49%. After PCV13 introduction in Mongolia, the incidence of more specific pneumonia endpoints declined in children 2-59 months of age; additional benefits were conferred by catch-up campaigns.

Adult Pneumococcal Vaccination in Ghana: Current Status and Future Recommendations - Expert Opinion.

Vaccination programs have proven successful in the prevention and control of infectious diseases among children on a global scale, but the majority of adult populations remain unvaccinated. immunocompromised adults as well as older adults aged low-income countries as Streptococcus pneumoniae infections are associated with substantial morbidity and mortality among 65 years and above. Despite the introduction of pneumococcal conjugate vaccines (PCVs), the burden of vaccine-type serotypes remains high in there are no clear policies for adult vaccination. As per the Global Burden of Disease 2019 report, about 120,000 individuals aged 70 years and older died as a result of LRTIs) in sub-Saharan Africa. A medical advisory board meeting was conducted in April 2022 to discuss the burden of pneumococcal diseases in adults, the current status of policies and practices of adult vaccination, unmet needs, and challenges in Ghana. This expert opinion paper outlines the pneumococcal epidemiology and burden of disease in Ghana, as well as the rationale for adult pneumococcal vaccination. It also highlights the potential barriers to adult vaccination and offers recommendations to overcome these obstacles and enhance vaccine acceptance in Ghana.

Les programmes de vaccination ont prouvé leur succès dans la prévention et le contrôle des maladies infectieuses chez les enfants à l'échelle mondiale, mais la majorité des populations adultes restent non vaccinées. Les infections à Streptococcus pneumoniae sont associées à une morbidité et une mortalité substantielles chez les adultes immunodéprimés ainsi que chez les personnes âgées de 65 ans et plus. Malgré l'introduction des vaccins conjugués contre le pneumocoque (VCP), la charge des sérotypes vaccinaux reste élevée dans les pays à faible revenu car il n'existe pas de politiques claires en matière de vaccination des adultes. Selon le rapport sur la charge mondiale de morbidité de 2019, environ 120 000 personnes âgées de 70 ans et plus sont décédées des suites d'infections des voies respiratoires inférieures (IVRI) en Afrique subsaharienne. Une réunion du conseil consultatif médical a eu lieu en avril 2022 pour discuter du fardeau des maladies pneumococciques chez les adultes, de l'état actuel des politiques et pratiques de vaccination des adultes, des besoins non satisfaits et des défis au Ghana. Cet article d'opinion d'experts présente l'épidémiologie pneumococcique et le fardeau de la maladie au Ghana, ainsi que les arguments en faveur de la vaccination pneumococcique des adultes. Il met également en lumière les obstacles potentiels à la vaccination des adultes et propose des recommandations pour surmonter ces obstacles et améliorer l'acceptation des vaccins au Ghana. MOTS-CLÉS: Maladie pneumococcique, Fardeau de la maladie, Vaccin conjugué contre le pneumocoque, Vaccination des adultes, Streptococcus pneumoniae, Ghana, Défis de la vaccination, Immunisation des adultes, VCP-13, Pneumonie acquise en communauté.

IgG antibody response to pneumococcal-conjugated vaccine (Prevenar®13) in children with immunodeficiency disorders.

Measurement of anti-pneumococcal capsular polysaccharides (anti-PnPs) IgG titers is an important tool in the immunologic assessment of patients with suspected immunodeficiency disorders (ID) to reduce the morbi-mortality and minimize severe infections. Retrospectively, we studied the relationship among anti-PnPs IgG response to 3 doses of Prevenar®13, levels of immune system components, leukocyte populations, and clinical data in children with ID. Serum samples were collected at least 4 weeks post vaccination. Subsequently, multi-serotype enzyme-linked immunosorbent assay (ELISA) was performed. Eighty-seven children (under 12 years) were enrolled. Primary immunodeficiency disorder (PID) was the most common disorder (45) followed by possible immunodeficiency disorder (POID) (19), secondary immunodeficiency disorder (SID) (15), and mixed immunodeficiency disorder (MID) (8). The median age was 3 (1.50-5.33) years, 65% of patients were male. Deficient production of anti-PnPs IgG (titer ≤ 50 mg/L) was detected in 47 patients (54%), especially in the MID group, all of them under immunosuppressive therapy. In PCV13 responders, the mean of leukocyte population levels was higher with statistically significance differences in CD4 + /CD8 + T lymphocytes (p = 0.372, p = 0.014) and CD56 + /CD16 + NK (p = 0.016). Patients with previous bone marrow transplantation were the worst PCV13 responders. Pneumococcal IgG antibody titers (post-vaccination) along with clinical and analytical markers represented.

Invasive pneumococcal surveillance to assess the potential benefits of extended spectrum conjugate vaccines (PCV15/PCV20) in older adults.

The introduction of pneumococcal conjugate vaccines (PCV) into the childhood vaccination programme has reduced invasive pneumococcal disease (IPD). Although anticipated from data elsewhere, surveillance in Ireland has confirmed reductions in IPD amongst those ⩾65 years of age due to a decline of PCV serotypes in this age group. Currently, direct protection against IPD in the elderly is focused on immunisation with the 23-valent pneumococcal polysaccharide vaccine (PPV23). However, immunity may not be as effective as with PCV and, furthermore, PPV23 uptake is poor in Ireland. Hence, consideration should be given to providing a PCV to this age group.

Dynamics of invasive pneumococcal disease in infants < 2 years old following PCV7/13 implementation using two infant and a booster dose schedule: evidence for indirect protection of young infants, Israel, 2004 to 2019.

BackgroundPneumococcal conjugated vaccine (PCV)7 and PCV13 programmes started in Israel from July 2009 and November 2010 respectively, with a 2+1 schedule (one dose at 2 months old, one at 4 months old, and a booster dose at 12 months old). Thereafter, invasive pneumococcal disease (IPD) rates substantially declined in children. Uptake of all three doses in < 2-year-olds since 2012 is > 90%. For still incompletely vaccinated infants (≤ 12 months old), how well the PCV 2+1 programme shields from IPD is not fully resolved.AimTo assess the adequacy of protection conferred by the 2+1 schedule PCV vaccination programme, particularly among incompletely-vaccinated infants.MethodsThis was a population-based, prospective, nationwide active IPD surveillance study in Israel, 2004-2019, in children < 24 months old. We estimated annual incidence rates (IR) of overall IPD, IPD caused by PCV13 serotypes (VT13), and non-PCV13 serotypes (NVT13). Annual IPD IRs were stratified by age: < 4 months (receiving ≤ 1 dose), 4-6 months (immediately post dose 2), 7-12 months (a few months post dose 2), and 13-23 months (post dose 3). Late-PCV (2004-2008) to pre-PCV13 (2016-2019) mean annual IR ratios (IRRs) were calculated.Results2,569 IPD episodes were recorded. VT13 decreased > 90% in all age groups, while NVT13 seemed to increase. All-IPD rates declined in all age groups by 56-70%. The 2+1 schedule impact on 7-12-month-old infants (pre-booster) was similar to that on 13-23-month-old children (post booster), with PCV13 IPD reductions of 97% and 98%, respectively.ConclusionsIndirect (herd) protection of infants, including < 4 month-olds with ≤ 1 PCV dose, was achieved by the 2+1 PCV schedule programme which thus seems adequate.

Hearing outcomes in children with pneumococcal meningitis in the PCV13 era.

INTRODUCTION: Streptococcus pneumoniae, is associated with the highest incidence of post-meningitic SNHL. The exact impact of 13-valent pneumococcal conjugate vaccine (PCV) on pediatric SNHL from pneumococcal meningitis is unknown. We aimed to identify clinical factors associated with post-meningitic SNHL (pmSNHL) from pneumococcal meningitis and describe its rates based on three time periods: pre-PCV, PCV-7 and PCV13 eras. METHODS: A retrospective case-control study was performed for patients 18 years and younger diagnosed with pneumococcal meningitis from January 1, 2010 to December 31, 2020 at Children's Hospital Colorado. Demographic and clinical risk factors between those with or without SNHL were compared. Detailed hearing outcomes of those with resulting SNHL are described. RESULTS: 23 patients with CSF cultures or Meningitis/Encephalitis Panel positive for pneumococcal meningitis were identified. Twenty patients both survived the infection and had audiologic evaluation. Six patients had pmSNHL, with 50 % affected bilaterally. The rate of pmSNHL from S. pneumoniae in the PCV-13 era at our institution was similar to historical rates from the pre-PCV and PCV-7 eras. Similar proportions of patients with pmSNHL completed PCV vaccination (66.7 %) compared to those without (71.4 %). Non-PCV-13 serotypes were responsible 83 % of patients with pmSNHL versus 57 % of patients without pmSNHL. CONCLUSIONS: Despite high rates of PCV-13 uptake in our cohort, pmSNHL was still common, severe, and commonly associated with non-PCV-13 serotypes. Non-PCV-13 serotypes may be contributing to the persistently high rate of post-meningitic SNHL and the severity of SNHL. Newer pneumococcal conjugate vaccines with expanded serotypes may help mitigate the SNHL associated with pneumococcal meningitis.

The safety of pneumococcal vaccines at the time of sequential schedule: data from surveillance of adverse events following 13-valent conjugated pneumococcal and 23-valent polysaccharidic pneumococcal vaccines in newborns and the elderly, in Puglia (Italy), 2013-2020.

Background: Nowadays, two types of anti-pneumococcal vaccine are available: pneumococcal 13-valent conjugate vaccine (PCV13), first licensed in the United States (US) in 2013, and pneumococcal 23-valent polysaccaridic vaccine (PPSV23), first licensed in the US in 1999. These vaccines are recommended in Italy for the immunization of newborns and of the elderly, using a combined sequential schedule for the latter. This report aims to describe the PCV13- and PPSV23-related AEFIs notified in Puglia in 2013-2020, in order to design these products' safety profile in a real-life scenario, three years after the official recommendation about the sequential schedule for people over 60 years of age. Methods: This is a retrospective observational study. Data were gathered from the list of AEFIs notified following PCV13 and PPSV23 administration in Puglia in 2013-2020. The number of administered vaccine doses was obtained from the regional immunization database. AEFIs were classified according to WHO's algorithm, and causality assessment was carried out in case of serious AEFIs. Results: From January 2013 to December 2020, 764,183 doses of PCV13 and 40,382 doses of PPSV23 were administered in Puglia. In the same period, 71 PCV13 AEFIs (Reporting Rate: 9.29 x100,000 doses) and 5 PPSV23 AEFIs (Reporting Rate: 12.4 x100,000 doses) were reported. The overall male/female ratio in AEFIs was 0.85. The majority of AEFIs occurred in subjects aged less than 2 (64/76, 84.2%), while 10 out of 76 (13.2%) occurred in patients aged 60 or older. 22 AEFIs were classified as serious and for 12 (54.5%) causality assessment showed a consistent relationship with immunization. The most commonly reported symptoms were fever (Reporting Rate: 4.72 x100,000 doses) and neurological symptoms (Reporting Rate: 3.23 x100,000 doses). Only one death was notified, classified as non-vaccine-related. Conclusions: The benefit of pneumococcal vaccination appears to be greater than the risk of AEFIs for both PCV13 and PPSV23. In fact, AEFIs occur in less than 0.1‰ of patients and the majority of AEFIs are mild and self-limiting.

Thirteen-Valent Pneumococcal Conjugate Vaccine-Induced Immunoglobulin G (IgG) Responses in Serum Associated With Serotype-Specific IgG in the Lung.

Pneumococcal conjugate vaccine (PCV) efficacy is lower for noninvasive pneumonia than invasive disease. In this study, participants were immunized with 13-valent PCV (PCV13) or hepatitis A vaccine (control). Bronchoalveolar lavage samples were taken between 2 and 6 months and serum at 4 and 7 weeks postvaccination. In the lung, anti-capsular immunoglobulin G (IgG) levels were higher in the PCV13 group compared to controls for all serotypes, except 3 and 6B. Systemically, IgG levels were elevated in the PCV13 group at 4 weeks for all serotypes, except serotype 3. IgG in bronchoalveolar lavage and serum positively correlated for nearly all serotypes. PCV13 shows poor immunogenicity to serotype 3, implying lack of protective efficacy. Clinical Trials Registration. ISRCTN 45340436.

Effectiveness of Pneumococcal Vaccination Against Pneumococcal Pneumonia Hospitalization in Older Adults: A Prospective, Test-Negative Study.

BACKGROUND: Despite use of the 13-valent pneumococcal conjugate vaccine (PCV13) and 23-valent pneumococcal polysaccharide vaccine (PPSV23) over the last decade, the disease burden of pneumococcal pneumonia is still high. We evaluated the field effectiveness of PCV13, PPSV23, and sequential vaccination against pneumococcal pneumonia in older adults. METHODS: This prospective multicenter study was conducted in adults aged ≥65 years hospitalized with community-acquired pneumonia (CAP) between September 2015 and August 2017. The case-control test-negative design was used to estimate vaccine effectiveness (VE) against pneumococcal CAP. RESULTS: Of 1525 cases with CAP hospitalization, 167 (11.0%) were identified as pneumococcal CAP. In the elderly aged ≥65 years, the adjusted VE of pneumococcal vaccines against pneumococcal CAP was statistically insignificant: 40.0% (95% confidence interval [CI], -10.8% to 67.5%) for PCV13 and 11.0% (95% CI, -26.4% to 37.3%) for PPSV23. However, in the younger subgroup (aged 65-74 years), sequential PCV13/PPSV23 vaccination showed the highest adjusted VE of 80.3% (95% CI, 15.9%-95.4%), followed by single-dose PCV13 (adjusted VE, 66.4% [95% CI, .8%-88.6%]) and PPSV23 (adjusted VE, 18.5% [95% CI, -38.6% to 52.0%]). CONCLUSIONS: Sequential PCV13/PPSV23 vaccination is most effective for preventing pneumococcal CAP among the elderly aged 65-74 years.

Pneumococcal vaccination coverage in individuals (16-59 years) with a newly diagnosed risk condition in Germany.

BACKGROUND: Despite recommendations from the German Standing Committee on Vaccination (STIKO), pneumococcal vaccination coverage remains low in vulnerable populations. This study estimated the pneumococcal vaccination coverage rate (VCR) and timing among individuals aged 16-59 years in Germany who were recommended to receive pneumococcal vaccination, according to STIKO. METHODS: A retrospective cohort analysis was conducted using the German InGef database. Individuals aged 16 to 59 years diagnosed with at least one "at-risk" (chronic disease) or "high-risk" (e.g., immunocompromising) condition considered to be at-risk of pneumococcal infection were identified at the time of first diagnosis, between January 1, 2016 and December 31, 2018, and followed up until December 31, 2019. The percentage of cumulative pneumococcal VCR with 95% confidence interval (CI) was reported for each calendar year of follow-up. RESULTS: There were 334,292 individuals followed for a median of 2.38 (interquartile range (IQR) 1.63-3.13) person years. For individuals aged 16-59 years diagnosed with an incident risk condition in 2016, pneumococcal VCR increased from 0.44% (95% CI 0.41-0.48) in 2016 to 1.24% (95% CI 1.18-1.30) in 2019. In 2019, VCRs were higher in individuals with high-risk conditions compared with at-risk conditions (2.24% (95% CI 2.09-2.40) vs. 0.90% (95% CI 0.85-0.96)). In 2019, VCRs were higher in individuals aged 50 to 59 years compared with individuals aged 16 to 49 years (2.25% (95% CI 2.10-2.41) vs. 0.90% (95% CI 0.84-0.96)). Similar trends were observed in individuals with newly diagnosed risk conditions identified in 2017 and in 2018. Older age, influenza vaccination and increasing number of risk conditions increased the likelihood of pneumococcal vaccination. Median time to vaccination from diagnosis of the risk condition was shorter for high-risk conditions (369.5 days (IQR 155.8-702.0)) compared to at-risk conditions (435.5 days (IQR 196.3-758.8)). CONCLUSION: Despite recommendations from STIKO, pneumococcal vaccination coverage remains very low and with long delays in vulnerable individuals aged 16-59 in Germany. Further efforts are required to increase immunization levels and shorten time to vaccination among individuals 16-59 years of age developing conditions with higher susceptibility to pneumococcal infection.

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

BACKGROUND: Little 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. METHODS: The 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. RESULTS: The 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. CONCLUSIONS: This 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.

Marked Reduction of Socioeconomic and Racial Disparities in Invasive Pneumococcal Disease Associated With Conjugate Pneumococcal Vaccines.

BACKGROUND: It is not known whether reductions in socioeconomic and racial disparities in incidence of invasive pneumococcal disease (defined as the isolation of Streptococcus pneumoniae from a normally sterile body site) noted after pneumococcal conjugate vaccine (PCV) introduction have been sustained. METHODS: Individual-level data collected from 20 Tennessee counties participating in Active Bacterial Core surveillance over 19 years were linked to neighborhood-level socioeconomic factors. Incidence rates were analyzed across 3 periods-pre-7-valent PCV (pre-PCV7; 1998-1999), pre-13-valent PCV (pre-PCV13; 2001-2009), and post-PCV13 (2011-2016)-by socioeconomic factors. RESULTS: A total of 8491 cases of invasive pneumococcal disease were identified. Incidence for invasive pneumococcal disease decreased from 22.9 (1998-1999) to 17.9 (2001-2009) to 12.7 (2011-2016) cases per 100 000 person-years. Post-PCV13 incidence (95% confidence interval [CI]) of PCV13-serotype disease in high- and low-poverty neighborhoods was 3.1 (2.7-3.5) and 1.4 (1.0-1.8), respectively, compared with pre-PCV7 incidence of 17.8 (15.7-19.9) and 6.4 (4.9-7.9). Before PCV introduction, incidence (95% CI) of PCV13-serotype disease was higher in blacks than whites (17.3 [15.1-19.5] vs 11.8 [10.6-13.0], respectively); after introduction, PCV13-type disease incidence was greatly reduced in both groups (white: 2.7 [2.4-3.0]; black: 2.2 [1.8-2.6]). CONCLUSIONS: Introduction of PCV13 was associated with substantial reductions in overall incidence and socioeconomic and racial disparities in PCV13-serotype incidence.

Nationwide Trends of Invasive Pneumococcal Disease in Spain From 2009 Through 2019 in Children and Adults During the Pneumococcal Conjugate Vaccine Era.

BACKGROUND: Introduction of pneumococcal conjugate vaccines (PCVs) has reduced the disease caused by vaccine serotypes in children, providing herd protection to adults. However, the emergence of nonvaccine serotypes is of great concern worldwide. METHODS: This study includes national laboratory data from invasive pneumococcal disease (IPD) cases that affected pediatric and adult populations during 2009-2019. The impact of implementing different vaccine strategies for immunocompetent adults by comparing Spanish regions that used the 13-valent PCV (PCV13) vs regions that used the 23-valent pneumococcal polysaccharide vaccine (PPV23) was also analyzed for 2017-2019. RESULTS: The overall reductions in IPD cases by PCV13 serotypes in children and adults were 88% and 59%, respectively, during 2009-2019, with a constant increase in serotype 8 in adults since 2015. IPD cases by additional serotypes covered by PPV23 increased from 20% in 2009 to 52% in 2019. In children, serotype 24F was the most frequent in 2019, whereas serotypes 3 and 8 accounted for 36% of IPD cases in adults. Introduction of PCV13 or PPV23 in the adult calendar of certain Spanish regions reduced the IPD cases by PCV13 serotypes by up to 25% and 11%, respectively, showing a decrease of serotype 3 when PCV13 was used. CONCLUSIONS: Use of PCV13 in children has affected the epidemiology, reducing the burden of IPD in children but also in adults by herd protection; however, the increase in serotype 8 in adults is worrisome. Vaccination with PCV13 in adults seems to control IPD cases by PCV13 serotypes including serotype 3.

The Evolution and Distribution of Pneumococcal Serotypes in Adults Hospitalized With Community-Acquired Pneumonia in Spain Using a Serotype-Specific Urinary Antigen Detection Test: The CAPA Study, 2011-2018.

BACKGROUND: Spain introduced the 13-valent pneumococcal conjugate vaccine (PCV13) in the childhood National Immunization Program in 2015-2016 with coverage of 3 doses of 94.8% in 2018. We assessed the evolution of all pneumococcal, PCV13 vaccine type (VT), and experimental PCV20-VT (PCV13 + serotypes 8, 10A, 11A, 12F, 15B, 22F, 33F) hospitalized community-acquired pneumonia (CAP) in adults in Spain from 2011-2018. METHODS: A prospective observational study of immunocompetent adults (≥18 years) admitted to 4 Spanish hospitals with chest X-ray-confirmed CAP between November 2011 and November 2018. Microbiological confirmation was obtained using the Pfizer serotype-specific urinary antigen detection tests (UAD1/UAD2), BinaxNow test for urine, and conventional cultures of blood, pleural fluid, and high-quality sputum. RESULTS: Of 3107 adults hospitalized with CAP, 1943 were ≥65 years. Underlying conditions were present in 87% (n = 2704) of the participants. Among all patients, 895 (28.8%) had pneumococcal CAP and 439 (14.1%) had PCV13-VT CAP, decreasing from 17.9% (n = 77) to 13.2% (n = 68) from 2011-2012 to 2017-2018 (P = .049). PCV20-VT CAP occurred in 243 (23.8%) of those included in 2016-2018. The most identified serotypes were 3 and 8. Serotype 3 accounted for 6.9% (n = 215) of CAP cases, remaining stable during the study period, and was associated with disease severity. CONCLUSIONS: PCV13-VT caused a substantial proportion of CAP in Spanish immunocompetent adults 8 years after introduction of childhood PCV13 immunization. Improving direct PCV13 coverage of targeted adult populations could further reduce PCV13-VT burden, a benefit that could be increased further if PCV20 is licensed and implemented.

Hospitalization for Invasive Pneumococcal Diseases in Young Children before Use of 13-Valent Pneumococcal Conjugate Vaccine, Suzhou, China.

A 13-valent pneumococcal conjugate vaccine against invasive pneumococcal disease (IPD) was introduced in China in April 2017. We describe 105 children <5 years of age who were hospitalized for IPD at Soochow University Affiliated Children's Hospital in Suzhou, China, during January 2010-December 2017. We calculated the incidence of hospitalization for IPD as 14.55/100,000 children in Suzhou. We identified 8 different capsular serotypes: 6B (28.4% of cases), 14 (18.9% of cases), 19A (18.9% of cases), 19F (12.2% of cases), 23F (10.8% of cases), 20 (4.1% of cases), 9V (4.1% of cases), and 15B/C (2.7% of cases). These results provide baseline data of IPD before the introduction of this vaccine in China, enabling researchers to better understand its effects on IPD incidence.

Twenty-Year Public Health Impact of 7- and 13-Valent Pneumococcal Conjugate Vaccines in US Children.

Pneumococcal conjugate vaccines (PCVs) have been used in the United States since 2000. To assess the cumulative 20-year effect of PCVs on invasive pneumococcal disease (IPD) incidence among children <5 years of age, we analyzed Active Bacterial Core Surveillance data, conducted a literature review, and modeled expected and observed disease. We found that PCVs have averted >282,000 cases of IPD, including ≈16,000 meningitis, ≈172,000 bacteremia, and ≈55,000 bacteremic pneumonia cases. In addition, vaccination has prevented 97 million healthcare visits for otitis media, 438,914-706,345 hospitalizations for pneumonia, and 2,780 total deaths. IPD cases declined 91%, from 15,707 in 1997 to 1,382 in 2019. Average annual visits for otitis media declined 41%, from 78 visits/100 children before PCV introduction to 46 visits/100 children after PCV13 introduction. Annual pneumonia hospitalizations declined 66%-79%, from 110,000-175,000 in 1997 to 37,000 in 2019. These findings confirm the substantial benefits of PCVs for preventing IPD in children.

Nasopharyngeal carriage of Streptococcus pneumoniae among healthy children in Kassena-Nankana districts of Northern Ghana.

BACKGROUND: Pneumococcal vaccine immunizations may be responsible for alterations in serotype epidemiology within a region. This study investigated the pneumococcal carriage prevalence and the impact of the 13-valent pneumococcal conjugate vaccine (PCV-13) on circulating serotypes among healthy children in Northern Ghana. METHODS: This was a cross sectional study conducted in the Kassena-Nankana districts of Northern Ghana from November to December during the dry season of 2018. Nasopharyngeal swabs collected from 193 participants were cultured per standard microbiological protocols and pneumococcal isolates were serotyped using the latex agglutination technique and the capsular Quellung reaction test. We examined for any association between the demographic characteristics of study participants and pneumococcal carriage using chi-square test and logistic regression. RESULTS: Of the 193 participants that were enrolled the mean age was 8.6 years and 54.4% were females. The carriage rate among the participants was 32.6% (63/193), and twenty different serotypes were identified. These included both vaccine serotypes (VT), 35% (7/20) and non-vaccine serotypes (NVT), 65% (13/20). The predominant serotypes (34 and 11A), both of which were NVT, accounted for a prevalence of 12.8%. PCV-13 covered only 35% of serotypes identified whiles 40% of serotypes are covered by PPV 23. CONCLUSION: Post-vaccination carriage of S. pneumoniae is high and is dominated by non-vaccine serotypes. There is therefore a need for the conduct of invasive pneumococcal disease surveillance (IPD) to find out if the high non-vaccine serotype carriage translates to disease. And in addition, a review of the currently used PCV-13 vaccine in the country would be considered relevant.

Invasive pneumococcal disease in persons with predisposing factors is dominated by non-vaccine serotypes in Southwest Sweden.

BACKGROUND: The pneumococcal conjugate vaccine PCV7 was introduced in Southwest Sweden in the child vaccination program in 2009, followed by PCV13 in 2010 and PCV10 in 2015. In this retrospective cohort study we assessed the pneumococcal serotype distribution in relation to predisposing factors, clinical manifestations and outcome during seven years after PCV introduction. METHODS: Clinical data from 1278 patients with 1304 episodes of invasive pneumococcal disease (IPD) between January 2009 and December 2015 in Region Västra Götaland, Sweden, were retrospectively collected from medical records. Pneumococcal isolates were serotyped by gel diffusion and/or Quellung reactions performed at the Public Health Agency in Sweden. Associations between serotypes and clinical characteristics were statistically evaluated by use of Fisher's exact test, Mann-Whitney U test and Logistic regression analysis, whereas IPD episodes caused by serotypes over time were analyzed by Mantel-Haenszel chi-square test. RESULTS: With the exception of serotype 3, the prevalence of PCV13 serotypes decreased during the study period, from 76% (n = 157) of all IPD episodes in 2009 to 25% (n = 42) in 2015 (p < 0.001) while non-PCV13 serotypes increased, mainly among patients ≥65 years and in patients with predisposing factors, including cardiovascular disease, pulmonary disease and malignancy (p < 0.001 for all). Patients with predisposing factors, including those with malignancy, immune deficiency or renal disease, were more likely to have IPD caused by a serotype not included in PCV13 rather than a vaccine-included serotype. Serotype 3 was associated with intensive care unit admissions while serotype 1 and 7F caused IPD among healthier and younger patients. PCV13 serotypes were associated with invasive pneumonia, and non-PCV13 serotypes were associated with bacteremia with unknown focus and with manifestations other than pneumonia or meningitis. CONCLUSIONS: Non-PCV13 serotypes caused the majority of IPD cases in Southwest Sweden, especially in patients ≥65 years and in patients with predisposing factors. Serotype 3, included in PCV13, was prevalent and often caused severe disease.