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Acta Microbiologica Et Immunologica... Jul 2024The worldwide burden of disease of bacterial meningitis remains high, despite the decreasing incidence following introduction of routine vaccination campaigns.The aim of...
The worldwide burden of disease of bacterial meningitis remains high, despite the decreasing incidence following introduction of routine vaccination campaigns.The aim of our study was to evaluate the epidemiological and bacteriological profile of paediatric bacterial meningitis (BM) in Tunisian children, during the period 2003-2019, following the implementation of Haemophilus influenzae type b (Hib) vaccine (April 2011) and before 10-valent pneumoccocal conjugate vaccine (PCV10) introduction to the childhood immunization program.All bacteriologically confirmed cases of BM admitted to children's hospital of Tunis were recorded (January 2003 to April 2019). Serogroups of Neisseria meningitidis (Nm) and serotypes of Streptococcus pneumoniae (Sp) and H. influenzae (Hi) and antibiotic resistance were determined using conventional and molecular methods.Among 388 cases, the most frequent species were Sp (51.3%), followed by Nm (27.5%) and Hi (16.8%). We observed a significant decrease in Hi BM rate during the conjugated Hib vaccine use period (P < 0.0001). The main pneumococcal serotypes were 14, 19F, 6B, 23F and 19A and the serotype coverage of PCV10, PCV13, PCV15 and PCV20 was 71.3 and 78.8%, 79.4 and 81.9% respectively. The most frequent Nm serogroup was B (83.1%). Most Hi strains were of serotype b (86.9%). High levels of resistance were found: Sp and Nm to penicillin (respectively 60.1 and 80%) and Hi to ampicillin (42.6%). All meningococcal and Hi isolates were susceptible to third-generation cephalosporins and 7.2% of pneumococcal strains had decreased susceptibility to these antibiotics.The Hib conjugate vaccine decreased the rate of BM. Sp dominated the aetiology of BM in children in Tunisia. Conjugate vaccines introducing decreases not only BM cases but also antimicrobial resistance.
Topics: Humans; Tunisia; Child, Preschool; Infant; Streptococcus pneumoniae; Meningitis, Bacterial; Neisseria meningitidis; Male; Female; Child; Pneumococcal Vaccines; Anti-Bacterial Agents; Haemophilus influenzae; Haemophilus Vaccines; Serogroup; Drug Resistance, Bacterial; Microbial Sensitivity Tests; Infant, Newborn; Adolescent; Bacterial Capsules
PubMed: 38771654
DOI: 10.1556/030.2024.02208 -
ACS Infectious Diseases Jun 2024Serotypes 6C and 6D of are two major variants that cause invasive pneumococcal disease (IPD) in serogroup 6 alongside serotypes 6A and 6B. Since the introduction of the...
Serotypes 6C and 6D of are two major variants that cause invasive pneumococcal disease (IPD) in serogroup 6 alongside serotypes 6A and 6B. Since the introduction of the pneumococcal conjugate vaccines PCV7 and PCV13, the number of cases of IPD caused by pneumococcus in children and the elderly population has greatly decreased. However, with the widespread use of vaccines, a replacement effect has recently been observed among different serotypes and lowered the effectiveness of the vaccines. To investigate protection against the original serotypes and to explore protection against variants and replacement serotypes, we created a library of oligosaccharide fragments derived from the repeating units of the capsular polysaccharides of serotypes 6A, 6B, 6C, and 6D through chemical synthesis. The library includes nine pseudosaccharides with or without exposed terminal phosphate groups and four pseudotetrasaccharides bridged by phosphate groups. Six carbohydrate antigens related to 6C and 6D were prepared as glycoprotein vaccines for immunogenicity studies. Two 6A and two 6B glycoconjugate vaccines from previous studies were included in immunogenicity studies. We found that the conjugates containing four phosphate-bridged pseudotetrasaccharides were able to induce good immune antibodies and cross-immunogenicity by showing superior activity and broad cross-protective activity in OPKA bactericidal experiments.
Topics: Streptococcus pneumoniae; Oligosaccharides; Serogroup; Pneumococcal Vaccines; Pneumococcal Infections; Antibodies, Bacterial; Animals; Mice; Bacterial Capsules; Humans; Female
PubMed: 38770797
DOI: 10.1021/acsinfecdis.4c00147 -
Open Forum Infectious Diseases May 2024Global use of pneumococcal conjugate vaccines (PCVs) with increasingly broader serotype coverage has helped to reduce the burden of pneumococcal disease in children and... (Review)
Review
Global use of pneumococcal conjugate vaccines (PCVs) with increasingly broader serotype coverage has helped to reduce the burden of pneumococcal disease in children and adults. In clinical studies comparing PCVs, higher-valency PCVs have met noninferiority criteria (based on immunoglobulin G geometric mean concentrations and response rates) for most shared serotypes. A numeric trend of declining immunogenicity against shared serotypes with higher-valency PCVs has also been observed; however, the clinical relevance is uncertain, warranting additional research to evaluate the effectiveness of new vaccines. Novel conjugation processes, carriers, adjuvants, and vaccine platforms are approaches that could help maintain or improve immunogenicity and subsequent vaccine effectiveness while achieving broader protection with increasing valency in pneumococcal vaccines.
PubMed: 38770212
DOI: 10.1093/ofid/ofae220 -
PloS One 2024Streptococcus pneumoniae is a leading cause of morbidity and mortality globally, causing bacteremic pneumonia, meningitis, sepsis, and other invasive pneumococcal... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Streptococcus pneumoniae is a leading cause of morbidity and mortality globally, causing bacteremic pneumonia, meningitis, sepsis, and other invasive pneumococcal diseases. Evidence supports nasopharyngeal pneumococcal carriage as a reservoir for transmission and precursor of pneumococcal disease.
OBJECTIVES
To estimate the pneumococcal nasopharyngeal burden in all age groups in Latin America and the Caribbean (LAC) before, during, and after the introduction of pneumococcal vaccine conjugate (PVC).
METHODS
Systematic literature review of international, regional, and country-published and unpublished data, together with reports including data from serotype distribution in nasopharyngeal carriage in children and adults from LAC countries following Cochrane methods. The protocol was registered in PROSPERO database (ID: CRD42023392097).
RESULTS
We included 54 studies with data on nasopharyngeal pneumococcal carriage and serotypes from 31,803 patients. In children under five years old, carriage was found in 41% and in adults over 65, it was 26%. During the study period, children under five showed a colonization proportion of 34% with PCV10 serotypes and 45% with PCV13 serotypes. When we analyze the carriage prevalence of PCV serotypes in all age groups between 1995 and 2019, serotypes included in PCV10 and those included in PCV13, both showed a decreasing trend along analysis by lustrum.
CONCLUSION
The data presented in this study highlights the need to establish national surveillance programs to monitor pneumococcal nasopharyngeal carriage to monitor serotype prevalence and replacement before and after including new pneumococcal vaccines in the region. In addition, to analyze differences in the prevalence of serotypes between countries, emphasize the importance of approaches to local realities to reduce IPD effectively.
Topics: Humans; Streptococcus pneumoniae; Latin America; Caribbean Region; Nasopharynx; Pneumococcal Infections; Carrier State; Pneumococcal Vaccines; Serogroup; Child, Preschool; Adult; Child; Prevalence
PubMed: 38768099
DOI: 10.1371/journal.pone.0297767 -
Vaccine Jul 2024Pneumococcal disease, presenting as invasive pneumococcal disease (IPD) or community-acquired pneumonia (CAP) is an important cause of illness and hospitalisation in the...
Pneumococcal disease, presenting as invasive pneumococcal disease (IPD) or community-acquired pneumonia (CAP) is an important cause of illness and hospitalisation in the elderly. To reduce pneumococcal burden, since 2003, 65-year-olds in England have been offered a 23-valent pneumococcal polysaccharide vaccine (PPV23). This study compares the impact and cost-effectiveness (CE) of vaccination with the existing PPV23 vaccine to the new 15-and 20-valent pneumococcal conjugate vaccines (PCV15 and PCV20), targeting adults aged 65 or 75 years old. We developed a static Markov model for immunisation against pneumococcal disease, capturing different vaccine effectiveness and immunity waning assumptions, projecting the number of IPD/CAP cases averted over the thirty years following vaccination. Using an economic model and probabilistic sensitivity analysis we evaluated the CE of the different immunisation strategies at current vaccine list prices and the willingness-to-pay at a median threshold of £20,000/QALY and an uncertainty threshold of 90% of simulations below £30,000/QALY. PCV20 averted more IPD and CAP cases than PCV15 or PPV23 over the thirty years following vaccination: 353(360), 145(159) and 150(174) IPD and 581(673), 259(485) and 212(235) CAP cases at a vaccination age of 65(75) under base vaccine effectiveness assumptions. At the listed prices of PCV20 and PPV23 vaccines as of May 2023, both vaccines were cost-effective when vaccinating 65- or 75-year-olds with an ICER threshold of £20,000 per QALY. To achieve the same cost-effectiveness as PPV23, the additional cost of PCV20 should be less than £44(£91) at an ICER threshold of £20,000/QALY (£30,000/QALY) if vaccination age is 65 (or £54(£103) if vaccination age is increased to 75). We showed that both PPV23 and PCV20 were likely to be cost-effective. PCV20 was likely to avert more cases of pneumococcal disease in elderly adults in England than the current PPV23 vaccine, given input assumptions of a higher vaccine effectiveness and slower waning for PCV20.
Topics: Humans; Pneumococcal Vaccines; Cost-Benefit Analysis; Aged; England; Pneumococcal Infections; Male; Female; Vaccination; Aged, 80 and over; Vaccines, Conjugate; Community-Acquired Infections; Markov Chains; Quality-Adjusted Life Years
PubMed: 38763851
DOI: 10.1016/j.vaccine.2024.05.001 -
Vaccine May 2024Otitis media (OM) is a prevalent respiratory disease in children and poses significant public health challenges due to its impact on child health and economic burdens....
BACKGROUND
Otitis media (OM) is a prevalent respiratory disease in children and poses significant public health challenges due to its impact on child health and economic burdens. However, there have no nationwide epidemiological studies conducted in Japan. This study investigates the epidemiological trends of OM in Japan, taking into account the impact of the 7-valent pneumococcal conjugate vaccine (PCV7) introduction.
METHOD
This study was retrospective cohort study using secondary data on the nationwide longitudinal birth cohort. This survey followed two cohorts born in 2001 (pre-PCV era) and 2010 (post-PCV era) until the age of 9. Every year, parents were surveyed about their children's health status, including occurrences of OM. The annual period prevalence and cumulative incidence of OM were assessed in this study, and the two cohorts were compared using a modified Poisson regression model adjusted environmental factors with the 2001 cohort as reference.
RESULT
The study included 47,015 children from the 2001 cohort and 38,554 from the 2010 cohort. Peak annual period prevalence of OM varied by era. Cumulative incidence was 13.8 % for the 2001 cohort and 18.5 % for the 2010 cohort by 1.5 years of age and 28.9 % and 33.3 %, respectively, by 3.5 years of age. In particular, from the fourth survey onward, covering ages 2.5-3.5 years, a shift was observed from an increased risk to a decreased risk of OM.
CONCLUSION
This nationwide longitudinal study emphasizes variations in OM epidemiology across Japan over time, with changes potentially influenced by the introduction of PCV7. In this study, due to the absence of individual PCV7 vaccination data, the effect of PCV7 was estimated based on the vaccination rate at the population level. The results suggest a notable decrease in the incidence of OM in later years, aligning with the increased uptake of PCV7.
PubMed: 38760268
DOI: 10.1016/j.vaccine.2024.05.020 -
The Pediatric Infectious Disease Journal Feb 2024We evaluated whether the quantification of IgG to pneumococcal capsular polysaccharides is an accurate diagnostic test for pneumococcal infection in children with...
Evaluation of Acute and Convalescent Antibody Concentration Against Pneumococcal Capsular Polysaccharides for the Diagnosis of Pneumococcal Infection in Children with Community-Acquired Pneumonia.
We evaluated whether the quantification of IgG to pneumococcal capsular polysaccharides is an accurate diagnostic test for pneumococcal infection in children with pneumonia in Nepal. Children with pneumococcal pneumonia did not have higher convalescent, or higher fold change, IgG to pneumococcal polysaccharides than children with other causes of pneumonia. Caution is needed in interpreting antibody responses in pneumococcal infections.
Topics: Humans; Antibodies, Bacterial; Child, Preschool; Polysaccharides, Bacterial; Immunoglobulin G; Infant; Streptococcus pneumoniae; Pneumonia, Pneumococcal; Community-Acquired Infections; Male; Female; Child; Nepal; Bacterial Capsules
PubMed: 38758207
DOI: 10.1097/INF.0000000000004185 -
Influenza and Other Respiratory Viruses May 2024Data available for RSV and influenza infections among children < 2 years in Mongolia are limited. We present data from four districts of Ulaanbaatar from April 2015...
BACKGROUND
Data available for RSV and influenza infections among children < 2 years in Mongolia are limited. We present data from four districts of Ulaanbaatar from April 2015 to June 2021.
METHODS
This study was nested in an enhanced surveillance project evaluating pneumococcal conjugate vaccine (PCV13) impact on the incidence of hospitalized lower respiratory tract infections (LRTIs). Our study was restricted to children aged < 2 years with arterial O saturation < 93% and children with radiological pneumonia. Nasopharyngeal (NP) swabs collected at admission were tested for RSV and influenza using qRT-PCR. NP swabs of all patients with radiological pneumonia and of a subset of randomly selected NP swabs were tested for S. pneumoniae (S.p.) by qPCR and for serotypes by culture and DNA microarray.
RESULTS
Among 5705 patients, 2113 (37.0%) and 386 (6.8%) had RSV and influenza infections, respectively. Children aged 2-6 months had a higher percentage of very severe RSV infection compared to those older than 6 months (42.2% versus 31.4%, p-value Fisher's exact = 0.001). S.p. carriage was detected in 1073/2281 (47.0%) patients. Among S.p. carriage cases, 363/1073 (33.8%) had S.p. and RSV codetection, and 82/1073 (7.6%) had S.p. and influenza codetection. S.p. codetection with RSV/influenza was not associated with more severe LRTIs, compared to only RSV/influenza cases.
CONCLUSION
In Mongolia, RSV is an important pathogen causing more severe LRTI in children under 6 months of age. Codetection of RSV or influenza virus and S.p. was not associated with increased severity.
Topics: Humans; Mongolia; Respiratory Syncytial Virus Infections; Infant; Influenza, Human; Female; Male; Respiratory Syncytial Virus, Human; Child, Preschool; Nasopharynx; Infant, Newborn; Incidence; Hospitalization; Streptococcus pneumoniae; Respiratory Tract Infections
PubMed: 38757258
DOI: 10.1111/irv.13303 -
Frontiers in Pediatrics 2024Pretransplant vaccination is generally recommended to solid organ transplant recipients. In infants with congenital nephrotic syndrome (CNS), the immune response is...
BACKGROUND
Pretransplant vaccination is generally recommended to solid organ transplant recipients. In infants with congenital nephrotic syndrome (CNS), the immune response is hypothetically inferior to other patients due to young age and urinary loss of immunoglobulins, but data on the immunization response in severely nephrotic children remain scarce. If effective, however, early immunization of infants with CNS would clinically be advantageous.
METHODS
We investigated serological vaccine responses in seven children with CNS who were immunized during nephrosis. Antibody responses to measles-mumps-rubella -vaccine (MMR), a pentavalent DTaP-IPV-Hib -vaccine (diphtheria, tetanus, acellular pertussis, inactivated poliovirus, type b), varicella vaccine, combined hepatitis A and B vaccine, and pneumococcal conjugate vaccine (PCV) were measured after nephrectomy either before or after kidney transplantation.
RESULTS
Immunizations were started at a median age of 7 months [interquartile range (IQR) 7-8], with a concurrent median proteinuria of 36,500 mg/L (IQR 30,900-64,250). Bilateral nephrectomy was performed at a median age of 20 months (IQR 14-25), and kidney transplantation 10-88 days after the nephrectomy. Antibody levels were measured at median 18 months (IQR 6-23) after immunization. Protective antibody levels were detected in all examined children for hepatitis B (5/5), (7/7), rubella virus (2/2), and mumps virus (1/1); in 5/6 children for varicella; in 4/6 for poliovirus and vaccine-type pneumococcal serotypes; in 4/7 for type B and ; in 1/2 for measles virus; and in 2/5 for hepatitis A. None of the seven children had protective IgG levels against .
CONCLUSION
Immunization during severe congenital proteinuria resulted in variable serological responses, with both vaccine- and patient-related differences. Nephrosis appears not to be a barrier to successful immunization.
PubMed: 38756974
DOI: 10.3389/fped.2024.1392873 -
Clinical and Experimental Vaccine... Apr 2024This narrative review describes genomic characteristic, serotyping, immunogenicity, and vaccine development of capsular polysaccharide (CPS). CPS is a primary virulence... (Review)
Review
This narrative review describes genomic characteristic, serotyping, immunogenicity, and vaccine development of capsular polysaccharide (CPS). CPS is a primary virulence factor of . The genomic characteristics of CPS, including the role of biosynthetic gene and genetic variation within (capsule polysaccharide) locus which may lead to serotype replacement are still being investigated. One hundred unique serotypes of have been identified through various methods of serotyping using phenotypic and genotypic approach. The advantages and limitations of each method are various, emphasizing the need for accurate and comprehensive serotyping for effective disease surveillance and vaccine targeting. In addition, we elaborate the critical role of CPS in vaccine development by providing an overview of immunogenicity, ongoing research of pneumococcal vaccines, and the impact on disease burden.
PubMed: 38752009
DOI: 10.7774/cevr.2024.13.2.91