Evaluating the health and economic outcomes of a PCV15 vaccination program for adults aged 65 years-and-above in Switzerland.

OBJECTIVE: To assess the health and economic outcomes of a PCV13 or PCV15 age-based (65 years-and-above) vaccination program in Switzerland. INTERVENTIONS: The three vaccination strategies examined were:Target population: All adults aged 65 years-and-above. Perspective(s): Switzerland health care payer. TIME HORIZON: 35 years. Discount rate: 3.0%. Costing year: 2023 Swiss Francs (CHF). STUDY DESIGN: A static Markov state-transition model. DATA SOURCES: Published literature and publicly available databases or reports. OUTCOME MEASURES: Pneumococcal diseases (PD) i.e., invasive pneumococcal diseases (IPD) and non-bacteremic pneumococcal pneumonia (NBPP); total quality-adjusted life-years (QALYs), total costs and incremental cost-effectiveness ratios (CHF/QALY gained). RESULTS: Using an assumed coverage of 60%, the PCV15 strategy prevented a substantially higher number of cases/deaths than the PCV13 strategy when compared to the No vaccination strategy (1,078 IPD; 21,155 NBPP; 493 deaths). The overall total QALYs were 10,364,620 (PCV15), 10,364,070 (PCV13), and 10,362,490 (no vaccination). The associated overall total costs were CHF 741,949,814 (PCV15), CHF 756,051,954 (PCV13) and CHF 698,329,579 (no vaccination). Thus, the PCV13 strategy was strongly dominated by the PCV15 strategy. The ICER of the PCV15 strategy (vs. no vaccination) was CHF 20,479/QALY gained. In two scenario analyses where the vaccine effectiveness for serotype 3 were reduced (75% to 39.3% for IPD; 45% to 23.6% for NBPP) and NBPP incidence was increased (from 1,346 to 1,636/100,000), the resulting ICERs were CHF 29,432 and CHF 13,700/QALY gained, respectively. The deterministic and probabilistic sensitivity analyses demonstrated the robustness of the qualitative results-the estimated ICERs for the PCV15 strategy (vs. No vaccination) were all below CHF 30,000/QALYs gained. CONCLUSIONS: These results demonstrate that using PCV15 among adults aged 65 years-and-above can prevent a substantial number of PD cases and deaths while remaining cost-effective over a range of inputs and scenarios.

Traditional Japanese herbal medicine Hochuekkito protects development of sepsis after nasal colonization in mice.

INTRODUCTION: Streptococcus pneumoniae, a commensal in the nasopharynx, can cause invasive pneumococcal diseases (IPDs). To prevent the aggravation of IPDs, it is important to enhance host immune defense against S. pneumoniae. Hochuekkito (HET) is expected to have an immunostimulatory effect against infections. METHODS: HET was administrated by gavage to adult BALB/cA mice before and after intranasal inoculation of S. pneumoniae. We evaluated the effect of HET on pneumococcal nasal colonization and subsequent development of lethal pneumococcal infections. RESULTS: No effect on nasal colonization was observed, but HET significantly reduced bacterial count in the blood, decreased the incidence of bacteremia, and improved survival. HET also reduced nasal tissue damage 3 days after intranasal infection. Neutrophils from HET-treated mice showed significantly higher bactericidal activity against S. pneumoniae in the presence of the serum from the HET group compared with from the control group. CONCLUSIONS: The non-specific immunostimulatory effect of HET is suggested by this study to be effective in preventing the progression in IPDs and provided insights into novel strategy in the post-pneumococcal vaccine era.

[Fatal invasive pneumococcal disease developed 14 years after allogeneic hematopoietic stem cell transplantation in a patient with myelodysplastic syndrome].

Invasive pneumococcal diseases (IPDs) after allogeneic hematopoietic stem cell transplantation have high fatality rates and often develop late after transplantation. The patient was a 58-year-old female. Fourteen years ago, she underwent bone marrow transplantation from a HLA-DR 1-antigen mismatched unrelated donor for myelodysplastic syndrome. She developed pneumonia, chronic graft-versus-host disease, and hypogammaglobulinemia. She received 23-valent pneumococcal capsular polysaccharide vaccine 11 and 6 years earlier. She was presented to our emergency room with fever. Her blood culture was positive for pneumococcus, and she was diagnosed with an IPD. The patient received antibiotic treatment but died on the third day of hospitalization. Because of its seriousness, pneumococcal infection should receive attention even 10 or more years after transplantation. Preventive approaches such as vaccination and early intervention at the time of diagnosis are important.

Cost-effectiveness of 20-valent pneumococcal conjugate vaccine compared with 23-valent pneumococcal polysaccharide vaccine among adults in a Norwegian setting.

BACKGROUND: The morbidity and mortality of adult diseases caused by S. pneumoniae increase with age and presence of underlying chronic diseases. Currently, two vaccine technologies against S. pneumoniae are used: the 23-valent pneumococcal polysaccharide vaccine (PPV23) and the pneumococcal conjugate vaccines, one of which is the 20-valent pneumococcal conjugate vaccine (PCV20) that has recently been approved for adults. OBJECTIVE: This study was conducted to investigate the cost-effectiveness of implementing PCV20 in a reimbursement scheme for Norwegian adults aged 18-99 years at risk of pneumococcal diseases and those aged 65 years and older at low risk compared to PPV23. METHODS: An established Markov model was adapted to a Norwegian setting to estimate the economic and clinical consequences of vaccinating the Norwegian population in specific age and risk groups against pneumococcal diseases. Inputs for the model were found in Norwegian or Danish real-world evidence or retrieved from available studies. The costs and clinical outcomes were assessed using a health sector perspective and a lifetime time horizon. RESULTS: The results showed that PCV20 was associated with better health outcomes including fewer disease cases, fewer disease-attributable fatalities, a higher gain of life years and quality-adjusted life years compared to PPV23. In addition, PCV20 had a lower total cost compared to PPV23. Therefore, PCV20 was the dominant vaccination strategy. The base case result was investigated in multiple sensitivity analyses, which showed that the results were robust to changes in input parameters and methodological assumptions, as PCV20 remained the dominant vaccination strategy in almost all scenarios. CONCLUSION: Results showed that vaccinating the Norwegian adults with PCV20 was cost-effective compared to PPV23. Changes in the hospital cost of pneumonia, the price of PCV 20, the effectiveness of PCV20 against pneumonia, and the pneumonia disease incidence had the highest impact on the ICER, i.e., were the main drivers of the results.

Cost-effectiveness analysis of pediatric immunization program with 15-valent pneumococcal conjugate vaccine in Japan.

BACKGROUND: The 15-valent pneumococcal conjugate vaccine (PCV15 or V114) has recently been approved for pediatric vaccination against pneumococcal diseases (PDs) in Japan. The study aims to evaluate the cost-effectiveness of pediatric vaccination with V114 versus 13-valent PCV (PCV13) in Japan. METHODS: The study used a decision analytical Markov model to estimate the cost and effectiveness outcomes for a birth cohort in Japan over a 10-year time horizon. The model tracked the occurrences of acute PD events, including invasive PD (IPD), non-bacteremic pneumococcal pneumonia (NBPP) and pneumococcal acute otitis media (AOM) and the long-term impact of post-meningitis sequalae. Vaccine effectiveness was estimated based on literature and assumptions, and accounted for indirect effects and vaccine waning. The base case took the societal perspective, including both direct and indirect costs, while a healthcare payer perspective was modeled in a scenario analysis. Additional scenario analyses and sensitivity analyses were conducted. RESULTS: In the base case, V114 was associated with an incremental gain of 24 quality-adjusted life years and a reduction of ¥365,610,955 in total costs compared to PCV13. It was expected to reduce the number of pneumococcal AOM, NBPP, and IPD cases by 1,832, 1,333 and 25, respectively. All scenario analyses and most sensitivity analyses showed that V114 was a dominant strategy compared to PCV13. CONCLUSIONS: Pediatric vaccination with V114 is expected to lead to cost savings and more health benefits compared to PCV13 in Japan from both societal and healthcare payer perspectives. The findings are robust under plausible assumptions and inputs.

Clinical characteristics and risk factors of pneumococcal diseases in recipients of allogeneic hematopoietic stem cell transplants in the late phase: A retrospective registry study.

Pneumococcal diseases are one of the most important infectious complications in the late period following allogeneic hematopoietic stem cell transplantation (allo-HSCT). The importance of long-term follow-up care is increasing, as the number of long-term survivors following allo-HSCT increases, but there has been a dearth of research specifically focusing on pneumococcal diseases during the late post-transplant period (day >100). Using a transplant registry database between January 1, 2001 and December 31, 2011, we aimed to assess the clinical spectrum and risk factors for pneumococcal diseases in the late post-transplant period. Among the 22,514 recipients who received allo-HSCT over an 11-year period and could be followed for ≥100 days, 43 patients developed 49 episodes of pneumococcal diseases. Six of the 43 patients died from pneumococcal diseases, and four of these six patients died within a week, despite having undergone allo-HSCT two or more years ago. A history of chronic graft-versus-host disease (odds ratio [OR], 2.31; 95% confidence interval [CI], 1.15-4.66; P = 0.02), viral infection (OR, 3.38; 95% CI, 1.70-6.72; P < 0.01), and complete remission of the underlying disease at the time of transplantation (OR, 2.38; 95%CI, 1.10-5.14; P = 0.03) were identified as risk factors. Given the risk of sudden death and the high mortality rate, attention should be paid to pneumococcal diseases in providing long-term follow-up care, even several years after allo-HSCT.

Chronic medical conditions associated with invasive pneumococcal diseases in inpatients in teaching hospitals in São Paulo city: Estimating antimicrobial susceptibility and serotype-coverage of pneumococcal vaccines.

BACKGROUND: Chronic conditions increase the risk of invasive pneumococcal diseases (IPD). Pneumococcal vaccination remarkably reduced IPD morbimortality in vulnerable populations. In Brazil, pneumococcal vaccines are included in the National Immunization Program (PNI): PCV10 for < 2 years-old, and PPV23 for high risk-patients aged ≥ 2 years and institutionalized ≥ 60 years. PCV13 is available in private clinics and recommended in the PNI for individuals with certain underlying conditions. METHODS: A retrospective study was performed using clinical data from all inpatients from five hospitals with IPD from 2016 to 2018 and the corresponding data on serotype and antimicrobial-non-susceptibility of pneumococcus. Vaccine-serotype-coverage was estimated. Patients were classified according to presence of comorbidities: healthy, without comorbidities; at-risk, included immunocompetent persons with specific medical conditions; high-risk, with immunocompromising conditions and others RESULTS: 406 IPD cases were evaluated. Among 324 cases with information on medical conditions, children < 5 years were mostly healthy (55.9%), while presence of comorbidity prevailed in adults ≥ 18 years old (> 82.0%). Presence of ≥1 risk condition was reported in ≥ 34.8% of adults. High-risk conditions were more frequent than at-risk in all age groups. Among high-risk comorbidity (n = 211), cancer (28%), HIV/AIDS (25.7%) and hematological diseases (24.5%) were the most frequent. Among at-risk conditions (n = 89), asthma (16.5%) and diabetes (8.1%) were the most frequent. Among 404 isolates, 42.9% belonged to five serotypes: 19A (14.1%), 3 (8.7%), 6C (7.7%), 4 and 8 (6.2% each); 19A and 6C expressed antimicrobial-non-susceptibility. The vaccine-serotype-coverage was: PCV10, 19.1%, PCV13, 43.8%; PCV15, 47.8%; PCV20, 62.9%; PCV21, 65.8%, and PPV23, 67.3%. Information on hospital outcome was available for 283 patients, of which 28.6% died. Mortality was 54.2% for those with meningitis. CONCLUSION: Vaccine with expanded valence of serotypes is necessary to offer broad prevention to IPD. The present data contribute to pneumococcal vaccination public health policies for vulnerable patients, mainly those with comorbidity and the elderly.

Cost-Effectiveness Analysis of Routine Use of 15-Valent Pneumococcal Conjugate Vaccine in the US Pediatric Population.

This study evaluated the clinical and economic impact of routine pediatric vaccination with the 15-valent pneumococcal conjugate vaccine (PCV15, V114) compared with the 13-valent PCV (PCV13) from a societal perspective in the United States (US). A Markov decision-analytic model was constructed to estimate the outcomes for the entire US population over a 100-year time horizon. The model estimated the impact of V114 versus PCV13 on pneumococcal disease (PD) incidence, post meningitis sequalae, and deaths, taking herd immunity effects into account. V114 effectiveness was extrapolated from the observed PCV13 data and PCV7 clinical trials. Costs (2021$) included vaccine acquisition and administration costs, direct medical costs for PD treatment, direct non-medical costs, and indirect costs, and were discounted at 3% per year. In the base case, V114 prevented 185,711 additional invasive pneumococcal disease, 987,727 all-cause pneumonia, and 11.2 million pneumococcal acute otitis media cases, compared with PCV13. This led to expected gains of 90,026 life years and 96,056 quality-adjusted life years with a total saving of $10.8 billion. Sensitivity analysis showed consistent results over plausible values of key model inputs and assumptions. The findings suggest that V114 is a cost-saving option compared to PCV13 in the routine pediatric vaccination program.

Serotype distribution and antimicrobial susceptibility of invasive Streptococcus pneumoniae isolates among adult and elderly population before and after introduction of pneumococcal conjugate vaccine in Casablanca, Morocco.

BACKGROUND: Streptococcus pneumoniae (S. pneumoniae), remains a major cause of mortality and morbidity worldwide. The objective of this study was to determine the trends of invasive pneumococcal diseases (IPD) in adult and elderly population in Casablanca (Morocco) before and after introduction of pneumococcal conjugate vaccine (PCV) by determining the distribution of pneumococcal serotypes and antibiotic resistance profile of isolated strains. METHOD: The proposed study is a retrospective laboratory-based surveillance of IPD in hospitalized adult (15-59 years old) and elderly (≥ 60 years old) patients in Ibn Rochd University Hospital Centre from 2007 to 2019 (13 years). All the 250 non-duplicate clinical invasive isolates from adult and elderly patients, confirmed as S. pneumoniae according to the laboratory standard identification procedures, are included in this study. RESULTS: A significant decrease of the overall incidence in IPD was observed only in adults from 0.71 to 0.54/100000 populations (P = 0.02) and to 0.47/100000 populations (P = 0.0137) in the early and mature post-vaccine period respectively compared to the pre-vaccine period. Our results also showed a significant reduction in the overall prevalence of vaccine serotypes from 28.17 to 6.90% (P = 0.0021) for the PCV-10 serotypes, and from 46.48 to 25.86% (P = 0.0164) for the PCV-13 serotypes only in the mature post-vaccine period (2015-2019). In parallel, the rate of non-vaccine serotypes did not significantly change in the early post-vaccine period (2011-2014) while it increased considerably from 54 to 74.14% (P = 0.0189) during the mature post-vaccine period. The rate of penicillin non-susceptible pneumococcal isolates decreased significantly from 23.94 to 8.77% (P = 0.02) in adult patients, and the rate of cotrimoxazole non-susceptible pneumococcal isolates significantly decreased from 29.58 to 8.77% in the early post-vaccine period (P = 0.003) and to 7.24% in the mature post-vaccine period (P = 0.0007). CONCLUSION: Although childhood vaccination has considerably reduced the incidence of IPD in adult population through the herd effect, IPD remain a real public health problem due to the alarming increase in non-vaccine serotypes (NVS) and the lack of herd effect among elderly population. The rate of antibiotic resistance was relatively low. Nevertheless, resistance constitutes a serious problem to the therapeutic arsenal due to the known capacity for genetic dissemination in the pneumococcus.

Chronic medical conditions associated with invasive pneumococcal diseases in inpatients in teaching hospitals in São Paulo city: Estimating antimicrobial susceptibility and serotype-coverage of pneumococcal vaccines

ABSTRACT Background: Chronic conditions increase the risk of invasive pneumococcal diseases (IPD). Pneumococcal vaccination remarkably reduced IPD morbimortality in vulnerable populations. In Brazil, pneumococcal vaccines are included in the National Immunization Program (PNI): PCV10 for < 2 years-old, and PPV23 for high risk-patients aged ≥ 2 years and institutionalized ≥ 60 years. PCV13 is available in private clinics and recommended in the PNI for individuals with certain underlying conditions. Methods: A retrospective study was performed using clinical data from all inpatients from five hospitals with IPD from 2016 to 2018 and the corresponding data on serotype and antimicrobial-non-susceptibility of pneumococcus. Vaccine-serotype-coverage was estimated. Patients were classified according to presence of comorbidities: healthy, without comorbidities; at-risk, included immunocompetent persons with specific medical conditions; high-risk, with immunocompromising conditions and others Results: 406 IPD cases were evaluated. Among 324 cases with information on medical conditions, children < 5 years were mostly healthy (55.9%), while presence of comorbidity prevailed in adults ≥ 18 years old (> 82.0%). Presence of ≥1 risk condition was reported in ≥ 34.8% of adults. High-risk conditions were more frequent than at-risk in all age groups. Among high-risk comorbidity (n = 211), cancer (28%), HIV/AIDS (25.7%) and hematological diseases (24.5%) were the most frequent. Among at-risk conditions (n = 89), asthma (16.5%) and diabetes (8.1%) were the most frequent. Among 404 isolates, 42.9% belonged to five serotypes: 19A (14.1%), 3 (8.7%), 6C (7.7%), 4 and 8 (6.2% each); 19A and 6C expressed antimicrobial-non-susceptibility. The vaccine-serotype-coverage was: PCV10, 19.1%, PCV13, 43.8%; PCV15, 47.8%; PCV20, 62.9%; PCV21, 65.8%, and PPV23, 67.3%. Information on hospital outcome was available for 283 patients, of which 28.6% died. Mortality was 54.2% for those with meningitis. Conclusion: Vaccine with expanded valence of serotypes is necessary to offer broad prevention to IPD. The present data contribute to pneumococcal vaccination public health policies for vulnerable patients, mainly those with comorbidity and the elderly.

Streptococcus pneumoniae Causing Invasive Diseases in Children and Adults in Central Thailand, 2012-2016.

Longitudinal data regarding the serotype distribution and antimicrobial susceptibility of S. pneumoniae-causing invasive pneumococcal disease (IPD) in developing countries are limited. Our aim was to monitor the antimicrobial susceptibility, serotype distribution, and serotype coverage rates of the pneumococcal conjugate vaccines (PCVs) and emerging non-vaccine serotypes (NVT) between 2012 and 2016 in central Thailand. Pneumococcal isolates from sterile specimens of patients, collected within a long-standing collaborative hospital network in central Thailand between 2012 and 2016, were studied. The pneumococcal serotypes included in the 15-valent PCV were identified by the quellung reaction, while the non-PCV15 serotypes were identified by multiplex PCR. Antimicrobial susceptibilities were determined by the microbroth dilution or disk diffusion method. Of the 276 pneumococcal isolates, 129 (46.7%) were from children aged ≤5 years. Only 9.0% of patients with available data received the PCV prior to the onset of the IPD. The most common vaccine serotypes were 6B (17.4%), 19A (13.0%), and 14 (11.2%), respectively. Non-PCV15 serotypes were detected in 27.9%; the most common serotypes were 15B/C (5.1%), 15A/F (4.0%), and 23A (3.6%), respectively. The serotype coverage rates of PCV10 in children aged ≤5 years was 55.8%, and 53.3% across all ages. PCV13 provided similar coverage rates to that of PCV15, 71.3% in children aged ≤5 years, and 72.1% across all ages. High susceptibilities to cefotaxime (94.6%), ofloxacin (98.2%), linezolid (99.6%), and vancomycin (100.0%) were observed, while the susceptibility to erythromycin (50.0%), TMP-SMZ (41.3%), and tetracycline (27.2%) were low. The susceptibilities to penicillin, meropenem, and clindamycin were 85.9%, 85.9%, and 84.8%, respectively. Serotype 19A was associated with a lower susceptibility than the non-19A isolates for penicillin (75.0% vs. 87.5%, p = 0.045), meropenem (52.8% vs. 90.8%, p < 0.001), erythromycin (33.3% vs. 53.8%, p = 0.022), and TMP-SMZ (16.7% vs. 45.0%, p = 0.001). Although the majority of the pneumococcal serotypes causing IPD in central Thailand were covered by the currently available PCVs, 25% of IPD were caused by NVT. Several emerging NVT identified were 15B/C, 15A/F, and 23A. The high rates of resistance to penicillin, meropenem, erythromycin, TMP-SMZ, and tetracycline observed is a major concern. Serotype 19A was associated with lower antimicrobial susceptibilities in comparison to the non-19A serotypes.

Increased Incidence of Invasive Pneumococcal Disease among Children after COVID-19 Pandemic, England.

During July-December 2021, after COVID-19 restrictions were removed in England, invasive pneumococcal disease incidence in children <15 years of age was higher (1.96/100,000 children) than during the same period in 2020 (0.7/100,000 children) and in prepandemic years 2017-2019 (1.43/100,000 children). Childhood vaccine coverage should be maintained to protect the population.

Return on Investment of 10-Valent Pneumococcal Conjugate Vaccine in Ecuador From 2010 to 2030.

OBJECTIVES: Ecuador introduced the pneumococcal conjugate vaccine in 2010. A recent time series analysis has demonstrated the impact of 10-valent pneumococcal conjugate vaccine (PCV10) on hospitalized pneumococcal disease in children. We leveraged these estimates to calculate the return on investment (ROI) of PCV10 in Ecuador from 2010 to 2030 at the national and regional levels. METHODS: We used 2 approaches to estimate the economic benefits: (1) cost of illness, which includes treatment, transportation, and productivity loss averted, (2) and the value of statistical life, which reflects society's average willingness to pay to save one life. Costs of the immunization program include vaccine costs (doses, syringes, injection supplies) and immunization delivery costs (personnel, cold chain equipment and maintenance, transportation, distribution services, and other recurrent costs). We estimated the ROI by dividing the net benefits by costs. RESULTS: The ROI using the cost-of-illness approach was slightly negative in the introduction year. From 2011 to 2020, we estimated the ROI to be 0.45 (0.15-0.73). For the future decade, the ROI is estimated at 0.37 (-0.03 to 1.03). Using the value-of-statistical-life approach, the ROI was 1.46 (0.82-2.17) in the introduction year. In the first decade, the ROI was 1.01 (0.49-1.60); in the second decade, the ROI fell to 0.83 (0.23-1.78). CONCLUSIONS: The results of this study demonstrate the total economic benefits of PCV10 in Ecuador exceed immunization program costs after the introduction year. Estimates from this study will inform country policy makers and will contribute to efforts to mobilize resources for immunization.

Does information by pharmacists convince the public to get vaccinated for pneumococcal disease and herpes zoster?

BACKGROUND: Pneumococcal diseases (PN) and herpes zoster (HZ) are preventable infections in the adult population. AIMS: This study aimed to identify the vaccination rates at 1 year after pharmacist-led provision of information in the community. The objectives were to reveal the reasons for not being vaccinated and to determine opinions and awareness of PN and HZ vaccination among public. METHODS: A prospective study was conducted in five social and solidarity centres in Turkey. Participants were educated by a pharmacist about PN and HZ diseases, vaccinations and reimbursement status, respectively. All participants were followed by telephone 1 year after to determine their vaccination status. RESULTS: A total of 155 participants (72.9% male; mean age was 68.72 ± 9.04 years) were included. With respect to PN and HZ vaccines, it was found that 40% and 12.7% of participants knew about the respective vaccines. Following the pharmacist's educational session, 52.9% and 51.6% were willing to have the respective vaccine, but only 5.7% and 0.8% respectively got vaccinated 1 year after the educational session. Perceived disease severity, provision of information by a pharmacist, and reimbursement status of the vaccines were not associated with the vaccination rates. CONCLUSIONS: The public obtain information on vaccines from friends and family members, which may result in misinformation and inappropriate behaviour in vaccination. Although educational sessions provided by pharmacists did not increase the actual vaccination rates for PN and HZ, public willingness to vaccination has increased.

Effectiveness of 23-Valent Pneumococcal Polysaccharide Vaccine Against Pneumococcal Diseases Among the Elderly Aged 60 Years or Older: A Matched Test Negative Case-Control Study in Shanghai, China.

Background:Streptococcus pneumoniae infection among adults, especially in adults over 60 years old in China results in a large number of hospitalizations and a substantial financial burden. This study assessed the vaccine effectiveness (VE) of 23-valent pneumococcal polysaccharide vaccine (PPV23) against pneumococcal diseases among the elderly aged 60 years or older in Shanghai, China. Methods: We conducted a test-negative case-control study among the elderly aged 60 years or older who sought care at hospitals in 13 districts of Shanghai from September 14, 2013 to August 31, 2019. A case was defined as pneumococcal disease and testing positive for Streptococcus pneumoniae. Controls had symptoms congruent with pneumococcal disease but were negative for Streptococcus pneumoniae. We conducted 1:2 matching by gender, age, hospital and admission date. Vaccination status was verified from the immunization system database. VE was calculated with conditional logistic regression according to the formula (1-OR) ×100%. Results: Overall, 603 adults aged 60 years or older with pneumococcal disease and positive for Streptococcus pneumoniae were included as cases, and 19.6% (118 persons) had a recorded PPV23 vaccination. The controls included 1,206 adults, whose vaccination rate was 23.8% (287 persons). The VE against pneumococcal diseases among the whole population was 24% (95% CI: 2%, 40%) and among women 44% (95% CI: 6%, 67%). After adjusting for multiple variables, the effectiveness of PPV23 against pneumococcal diseases was still statistically significant with VE for all of 25% (95% CI: 3%, 42%) and VE for women of 49% (95% CI: 11%, 71%). Conclusion: PPV23 was effective against pneumococcal diseases in adults aged 60 years or older in Shanghai, China. Its relatively high effectiveness among women warrants this group to be particularly targeted for vaccination, with further research on why vaccination effectiveness is less among men.

An Observational Prospective Cohort Study of Incidence and Outcome of Streptococcus pneumoniae and Hemophilus influenzae Infections in Adult Solid Organ Transplant Recipients.

BACKGROUND: Streptococcus pneumoniae (S. pneumoniae) and Hemophilus influenzae (H. influenzae) are among the main vaccine-preventable bacterial infections in immunocompromised individuals including solid organ transplant (SOT) recipients. There is a lack of information about incidence and outcomes of these infections in SOT recipients. METHODS: We determined the incidence of S. pneumoniae and H. influenzae, the related hospitalization, and 30- and 180-days mortality in a large cohort of 1182 adult SOT recipients. We calculated 95% confidence intervals (CI) of incidence rate (IR) using Byar's approximation to the Poisson distribution. RESULTS: The overall IR of S. pneumoniae and H. influenzae were 1086 (95% CI, 796-1448) and 1293 (95% CI, 974-1687) per 100,000 person-years of follow-up (PYFU), respectively. The IR of invasive infections were 76 (95% CI, 21-202) and 25 (95% CI, 2.3-118) per 100,000 PYFU, respectively. Hospital admission was required in >50%, 30-days mortality was 0, and 180-days mortality was 8.8% and 4.5% after S. pneumoniae and H. influenzae infections, respectively. CONCLUSIONS: The IR of invasive S. pneumoniae and H. influenzae infections in SOT recipients were much higher than reports from the general population in Denmark. Furthermore, a large proportion of infected SOT recipients were hospitalized. These findings highlight the need for further studies to assess uptake and immunogenicity of vaccines against S. pneumoniae and H. influenzae in SOT recipients.

Pneumococcal Disease Prevention: Are We on the Right Track?

The history of Streptococcus pneumoniae diseases dramatically changed with the introduction into the immunization schedule of infants and children of the first pneumococcal conjugate vaccine, the one containing 7 (PCV7) of the most common pneumococcal serotypes (STs) causing invasive pneumococcal diseases (IPDs). Where PCV7 was largely used, incidence of both IPDs and non-invasive pneumococcal diseases (nIPDs) in vaccinated children and in unvaccinated subjects of any age, mainly the elderly, significantly decreased. Unfortunately, the impact of PCV7 administration was slightly lower than expected, as the reduction in infections due to vaccine serotypes (STs) was accompanied by a significant increase in the number of IPDs and nIPDs due to STs not included in the vaccine. To overcome this problem, two PCVs containing 10 (PCV10) and 13 (PCV13) STs, chosen among those emerging, were developed and licensed. However, ST replacement occurred again. Moreover, the new PCVs showed little effectiveness in the prevention of infection due to non-encapsulated STs and to ST3. Next-generation S. pneumoniae vaccines able to prevent pneumococcal infections regardless of infecting ST are urgently needed. For the moment, the use of available PCVs remains fundamental because their benefits far outweigh any concerns for emerging STs.

Dynamics of antimicrobial resistance of Streptococcus pneumoniae following PCV10 introduction in Brazil: Nationwide surveillance from 2007 to 2019.

BACKGROUND: Brazil introduced 10-valent pneumococcal conjugate vaccine (PCV10) into its immunization program in 2010. We assessed antimicrobial susceptibility of Streptococcus pneumoniae (Spn) obtained from a national surveillance system for invasive pneumococcal diseases (IPD) before/after PCV10 introduction. METHODS: Antimicrobial non-susceptible isolates were defined as intermediate or resistant. Minimum inhibitory concentrations (MICs) to penicillin and ceftriaxone were analyzed by year. Antimicrobial susceptibility rates were assessed for each three-year-period using the pre-PCV10-period as reference. Susceptibility of vaccine-types was evaluated for 2017-2019. RESULTS: 11,380 isolates were studied. Spn with penicillin ≥ 0.125 mg/L and ceftriaxone ≥ 1.0 mg/L decreased in the three-years after PCV10 introduction (2011-2013: penicillin, 28.1-22.5%; ceftriaxone, 11.3%-7.6%) versus pre-PCV10-years (2007-2009: penicillin, 33.8-38.1%; ceftriaxone, 17.2%-15.6%). After 2013, the proportion of Spn with those MICs to penicillin and ceftriaxone increased to 39.4% and 19.7% in 2019, respectively. Non-susceptibility to penicillin and ceftriaxone increased in 2014-2016, and again in 2017-2019 especially among children < 5 years with meningitis (penicillin, 53.9%; ceftriaxone, 28.0%); multidrug-resistance reached 25% in 2017-2019. Serotypes 19A, 6C and 23A were most associated with antimicrobial non-susceptibility. CONCLUSIONS: Antimicrobial non-susceptible Spn decreased in the three-years after vaccination but subsequently increased and was associated with non-PCV10-types. Antimicrobial susceptibility surveillance is fundamental for guiding antibiotic therapy policies.

Pneumococcal infections and homelessness.

Objective: To assess the prevalence of pneumococcal nasopharyngeal carriage, the role of potential risk factors, and the pneumococcal vaccination coverage among sheltered homeless people in Marseille, France. Methods: During the winters 2015-2018, we enrolled 571 sheltered homeless males and 54 non-homeless controls. Streptococcus pneumoniae was directly searched from nasal/pharyngeal samples using real-time polymerase chain reaction. Results: The homeless people were mostly migrants from African countries, with a mean age of 43 years. Pneumococcal vaccination coverage was low (3.1%). The overall pneumococcal carriage rate was 13.0% and was significantly higher in homeless people (15.3% in 2018) than in controls (3.7%), with p = 0.033. Among homeless people, being aged ≥ 65 years (1.97, 95% CI; 1.01-3.87), living in a specific shelter (OR = 1.80, 95% CI: 1.06-3.05), and having respiratory signs and symptoms at the time of enrolment (OR = 2.55, 95% CI: 1.54-4.21) were independently associated with pneumococcal carriage. Conclusion: Pneumococcal nasopharyngeal carriage, which is a precursor for pneumococcal disease in at-risk individuals, is frequent among French homeless people. Studies conducted in other countries have also reported outbreaks of pneumococcal infections in homeless people. Pneumococcal vaccination should be systematically considered for sheltered homeless people in France, as is being done in Canada since 2008.