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Infectious Diseases and Therapy Dec 2021Streptococcus pneumoniae remains an important bacterial pathogen, particularly for young children in low- and middle-income countries. A systematic review was conducted... (Review)
Review
Streptococcus pneumoniae remains an important bacterial pathogen, particularly for young children in low- and middle-income countries. A systematic review was conducted of peer-reviewed literature from PubMed published as of May 13, 2020, to identify articles relevant to invasive pneumococcal disease, pneumonia, otitis media (OM), nasopharyngeal carriage (NPC), antimicrobial resistance (AMR), and vaccination coverage in Egypt, with particular focus on children ≤ 18 years of age. A total of 16 relevant articles spanning three decades were included in this review. Among studies reviewed, S. pneumoniae was the causative agent of meningitis in 21-30% of cases among hospitalized children between 1983 and 2003. One study showed that serotypes 6A and 6B predominated among meningitis cases of pediatric patients aged < 5 years. This review also revealed that S. pneumoniae was the most commonly identified bacterial pathogen of acute mastoiditis, a severe complication of acute OM, among children aged 9 months to 11 years. NPC studies showed that approximately 30% of Egyptian children were carriers of S. pneumoniae. AMR, especially to penicillin, continues to be a growing concern in low- and middle-income countries, including among Egyptian children. Several predominant serotypes were identified to be associated with penicillin resistance, such as 6B, 1, 19A, 23F, and 6A. Currently available pneumococcal vaccines (PCVs) such as PCV10 and PCV13 may provide coverage against the most prevalent circulating serotypes among Egyptian children. Comprehensive disease surveillance and immunization programs are needed to ensure that this vulnerable population is sufficiently protected against pneumococcal disease.
PubMed: 34468962
DOI: 10.1007/s40121-021-00523-6 -
Vaccine Aug 2021Streptococcus pneumoniae is one of the most common bacterial pathogens of infants and young children. Antibody responses against the pneumococcal polysaccharide capsule... (Review)
Review
BACKGROUND
Streptococcus pneumoniae is one of the most common bacterial pathogens of infants and young children. Antibody responses against the pneumococcal polysaccharide capsule are the basis of vaccine-mediated protection. We examined the relationship between the dose of polysaccharide in pneumococcal conjugate vaccines (PCVs) and immunogenicity.
METHODS
A systematic search of English publications that evaluated the immunogenicity of varying doses of pneumococcal conjugate vaccines was performed in Medline and Embase (Ovid Sp) databases in August 2019. We included only articles that involved administration of pneumococcal conjugate vaccine in humans and assessed the immunogenicity of more than one serotype-specific saccharide dose. Results were synthesised descriptively due to the heterogeneity of product valency, product content and vaccine schedule.
RESULTS
We identified 1691 articles after de-duplication; 9 studies met our inclusion criteria; 2 in adults, 6 in children and 1 in both. Doses of polysaccharide evaluated ranged from 0.44 mcg to 17.6 mcg. In infants, all doses tested elicited IgG geometric mean concentrations (GMCs) above the established correlate of protection (COP; 0.35 mcg/ml). A month after completion of the administered vaccine schedule, 95% confidence intervals of only three out of all the doses evaluated had GMCs that crossed below the COP. In the adult studies, all adults achieved GMCs that would be considered protective in children who have received 3 standard vaccine doses.
CONCLUSION
For some products, the mean antibody concentrations induced against some pneumococcal serotypes increased with increasing doses of the polysaccharide conjugate, but for other serotypes, there were no clear dose-response relationships or the dose response curves were negative. Fractional doses of polysaccharide which contain less than is included in currently distributed formulations may be useful in the development of higher valency vaccines, or dose-sparing delivery for paediatric use.
Topics: Adult; Antibodies, Bacterial; Child; Child, Preschool; Humans; Infant; Pneumococcal Infections; Pneumococcal Vaccines; Streptococcus pneumoniae; Vaccines, Conjugate
PubMed: 34340858
DOI: 10.1016/j.vaccine.2021.07.033 -
Clinical Infectious Diseases : An... Apr 2022Vaccine regulatory decision making is based on vaccine efficacy against etiologically confirmed outcomes, which may underestimate the preventable disease burden. To...
Vaccine-Preventable Disease Incidence Based on Clinically, Radiologically, and Etiologically Confirmed Outcomes: Systematic Literature Review and Re-analysis of Pneumococcal Conjugate Vaccine Efficacy Trials.
BACKGROUND
Vaccine regulatory decision making is based on vaccine efficacy against etiologically confirmed outcomes, which may underestimate the preventable disease burden. To quantify this underestimation, we compared vaccine-preventable disease incidence (VPDI) of clinically defined outcomes with radiologically/etiologically confirmed outcomes.
METHODS
We performed a systematic review of efficacy trials for several vaccines (1997-2019) and report results for pneumococcal conjugate vaccines. Data were extracted for outcomes within a clinical syndrome, organized from most sensitive to most specific. VPDI was determined for each outcome, and VPDI ratios were calculated, with a clinically defined outcome (numerator) and a radiologically/etiologically confirmed outcome (denominator).
RESULTS
Among 9 studies, we calculated 27 VPDI ratios; 24 had a value >1. Among children, VPDI ratios for clinically defined versus vaccine serotype otitis media were 0.6 (95% CI not calculable), 2.1 (1.5-3.0), and 3.7 (1.0-10.2); the VPDI ratios comparing clinically defined with radiologically confirmed pneumonia ranged from not calculable to 2.7 (1.2-10.4); the VPDI ratio comparing clinically suspected invasive pneumococcal disease (IPD) with laboratory-confirmed IPD was 3.8 (95% CI not calculable). Among adults, the ratio comparing clinically defined with radiologically confirmed pneumonia was 1.9 (-6.0 to 9.1) and with vaccine serotype-confirmed pneumonia was 2.9 (.5-7.8).
CONCLUSIONS
While there is substantial uncertainty around individual point estimates, there is a consistent trend in VPDI ratios, most commonly showing under-ascertainment of 1.5- to 4-fold, indicating that use of clinically defined outcomes is likely to provide a more accurate estimate of a pneumococcal conjugate vaccine's public health value.
Topics: Adult; Child; Humans; Incidence; Infant; Pneumococcal Infections; Pneumococcal Vaccines; Randomized Controlled Trials as Topic; Vaccine Efficacy; Vaccine-Preventable Diseases; Vaccines, Conjugate
PubMed: 34313721
DOI: 10.1093/cid/ciab649 -
Frontiers in Immunology 2021Immunization with tetanus-diphtheria-acellular pertussis (Tdap) vaccine in pregnancy is increasingly recommended. We determined the effect of Tdap immunization in... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Immunization with tetanus-diphtheria-acellular pertussis (Tdap) vaccine in pregnancy is increasingly recommended. We determined the effect of Tdap immunization in pregnancy on infants' vaccine responses.
METHODS
Individual-participant data meta-analysis of ten studies (n=1884) investigating infants' antibody response to routine immunizations following Tdap immunization in pregnancy was performed. Geometric mean ratios (GMRs) of antigen-specific immunoglobulin G (IgG) levels were calculated using mixed-effects models. Seroprotection rates were compared using chi-squared tests.
RESULTS
Infants of Tdap-immunized women had significantly lower IgG against pertussis toxin (GMR 0.65; 95%CI 0.57-0.74), filamentous haemagglutinin (FHA) (0.68; 0.53-0.87), pertactin (0.65; 0.58-0.72) and fimbria 2/3 (FIM2/3) (0.41; 0.32-0.52) after primary immunization, compared with infants of unimmunized women. These lower levels persisted after booster immunization for FHA (0.72; 0.61-0.84) and FIM2/3 (0.53; 0.29-0.96). After primary immunization, infants of Tdap-immunized women had lower seroprotection rates against diphtheria (90% [843/973] 98% [566/579]; p<0.001) and invasive pneumococcal disease (IPD) caused by 5 (SPN) serotypes (SPN5, SPN6B, SPN9V, SPN19A, SPN23F), and higher seroprotection rates against type b (short-term and long-term seroprotection rates, 86%[471/547] 76%[188/247] and 62%[337/547] 49%(121/247), respectively, all p=0.001). After booster immunization, seroprotection rates against diphtheria and tetanus were 99% (286/288) and (618/619) in infants of Tdap-immunized women, respectively.
CONCLUSIONS
Infants of Tdap-immunized women in pregnancy had lower IgG levels against pertussis, diphtheria and some SPN serotypes after their immunization compared with infants of unimmunized women. Enhanced surveillance of pertussis, diphtheria and IPD in infants is needed to determine the clinical significance of these findings.
SYSTEMATIC REVIEW REGISTRATION
CRD42017079171.
Topics: Antibodies, Bacterial; Diphtheria; Diphtheria-Tetanus-acellular Pertussis Vaccines; Female; Humans; Immunoglobulin G; Infant; Pregnancy; Tetanus; Vaccination; Whooping Cough
PubMed: 34305922
DOI: 10.3389/fimmu.2021.689394 -
The Cochrane Database of Systematic... Jul 2021Infectious diseases are a major cause of illness and death among older adults. Vaccines can prevent infectious diseases, including against seasonal influenza,...
BACKGROUND
Infectious diseases are a major cause of illness and death among older adults. Vaccines can prevent infectious diseases, including against seasonal influenza, pneumococcal diseases, herpes zoster and COVID-19. However, the uptake of vaccination among older adults varies across settings and groups. Communication with healthcare workers can play an important role in older people's decisions to vaccinate. To support an informed decision about vaccination, healthcare workers should be able to identify the older person's knowledge gaps, needs and concerns. They should also be able to share and discuss information about the person's disease risk and disease severity; the vaccine's effectiveness and safety; and practical information about how the person can access vaccines. Therefore, healthcare workers need good communication skills and to actively keep up-to-date with the latest evidence. An understanding of their perceptions and experiences of this communication can help us train and support healthcare workers and design good communication strategies.
OBJECTIVES
To explore healthcare workers' perceptions and experiences of communicating with older adults about vaccination.
SEARCH METHODS
We searched MEDLINE, CINAHL and Scopus on 21 March 2020. We also searched Epistemonikos for related reviews, searched grey literature sources, and carried out reference checking and citation searching to identify additional studies. We searched for studies in any language.
SELECTION CRITERIA
We included qualitative studies and mixed-methods studies with an identifiable qualitative component. We included studies that explored the perceptions and experiences of healthcare workers and other health system staff towards communication with adults over the age of 50 years or their informal caregivers about vaccination.
DATA COLLECTION AND ANALYSIS
We extracted data using a data extraction form designed for this review. We assessed methodological limitations using a list of predefined criteria. We extracted and assessed data regarding study authors' motivations for carrying out their study. We used a thematic synthesis approach to analyse and synthesise the evidence. We used the GRADE-CERQual (Confidence in the Evidence from Reviews of Qualitative research) approach to assess our confidence in each finding. We examined each review finding to identify factors that may influence intervention implementation and we developed implications for practice.
MAIN RESULTS
We included 11 studies in our review. Most studies explored healthcare workers' views and experiences about vaccination of older adults more broadly but also mentioned communication issues specifically. All studies were from high-income countries. The studies focused on doctors, nurses, pharmacists and others working in hospitals, clinics, pharmacies and nursing homes. These healthcare workers discussed different types of vaccines, including influenza, pneumococcal and herpes zoster vaccines. The review was carried out before COVID-19 vaccines were available. We downgraded our confidence in several of the findings from high confidence to moderate, low or very low confidence. One reason for this was that some findings were based on only small amounts of data. Another reason was that the findings were based on studies from only a few countries, making us unsure about the relevance of these findings to other settings. Healthcare workers reported that older adults asked about vaccination to different extents, ranging from not asking about vaccines at all, to great demand for information (high confidence finding). When the topic of vaccination was discussed, healthcare workers described a lack of information, and presence of misinformation, fears and concerns about vaccines among older adults (moderate confidence). The ways in which healthcare workers discussed vaccines with older adults appeared to be linked to what they saw as the aim of vaccination communication. Healthcare workers differed among themselves in their perceptions of this aim and about their own roles and the roles of older adults in vaccine decisions. Some healthcare workers thought it was important to provide information but emphasised the right and responsibility of older adults to decide for themselves. Others used information to persuade and convince older adults to vaccinate in order to increase 'compliance' and 'improve' vaccination rates, and in some cases to gain financial benefits. Other healthcare workers tailored their approach to what they believed the older adult needed or wanted (moderate confidence). Healthcare workers believed that older adults' decisions could be influenced by several factors, including the nature of the healthcare worker-patient relationship, the healthcare worker's status, and the extent to which healthcare workers led by example (low confidence). Our review also identified factors that are likely to influence how communication between healthcare workers and older adults take place. These included issues tied to healthcare workers' views and experiences regarding the diseases in question and the vaccines; as well as their views and experiences of the organisational and practical implementation of vaccine services.
AUTHORS' CONCLUSIONS
There is little research focusing specifically on healthcare workers' perceptions and experiences of communication with older adults about vaccination. The studies we identified suggest that healthcare workers differed among themselves in their perceptions about the aim of this communication and about the role of older adults in vaccine decisions. Based on these findings and the other findings in our review, we have developed a set of questions or prompts that may help health system planners or programme managers when planning or implementing strategies for vaccination communication between healthcare workers and older adults.
Topics: Age Factors; Aged; Caregivers; Communication; Decision Making; Health Knowledge, Attitudes, Practice; Health Personnel; Herpes Zoster Vaccine; Humans; Influenza Vaccines; Middle Aged; Persuasive Communication; Pneumococcal Vaccines; Professional-Family Relations; Qualitative Research; Vaccination; Vaccines
PubMed: 34282603
DOI: 10.1002/14651858.CD013706.pub2 -
Clinical and Experimental Vaccine... May 2021This systematic review and meta-analysis aims to quantify the impact of vaccination on the incidence and prevalence of nonsusceptible infections and investigates the... (Review)
Review
This systematic review and meta-analysis aims to quantify the impact of vaccination on the incidence and prevalence of nonsusceptible infections and investigates the impact of vaccination programs on serotype replacement. We searched a comprehensive set of databases. Identified studies were assessed using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach and resulting evidence was analyzed using random-effect meta-analyses. Nineteen studies on pneumococcal conjugate vaccines (PCV) met our inclusion criteria. PCV decreases the incidence of nonsusceptible pneumococcal infections (PIs) by 56.91% (95% confidence interval [CI], -50.90% to -62.91%) and the probability of carriage of nonsusceptible pneumococcal bacteria by 28.10% (95% CI, -13.25% to -42.95%). The effect of PCV on PIs becomes higher when only serotypes specifically targeted by the vaccine are taken into account (-80.98%; 95% CI, -70.34% to -91.52%), while it becomes lower when all the PIs, including both susceptible and nonsusceptible PIs, are considered (-48.30%; 95% CI, -31.55% to -65.08%). The effect of PCV is found greater in populations with high prevalence of human immunodeficiency virus and for PCV covering a higher number of serotypes. Findings from this study suggest that vaccination programs may be an effective tool to prevent the spread of PIs and may play a significant role in tackling antimicrobial resistance.
PubMed: 34222121
DOI: 10.7774/cevr.2021.10.2.81 -
The Pediatric Infectious Disease Journal Aug 2021Of children with acute otitis media (AOM), 15%-20% present with acute onset ear discharge due to a spontaneous perforation of the tympanic membrane (AOMd). This review...
BACKGROUND
Of children with acute otitis media (AOM), 15%-20% present with acute onset ear discharge due to a spontaneous perforation of the tympanic membrane (AOMd). This review aims to quantify the prevalence and antimicrobial resistance (AMR) status of bacteria in children with AOMd in the pneumococcal conjugate vaccine (PCV) era.
METHODS
Systematic searches were performed in PubMed, EMBASE and Cochrane Library from inception to June 7, 2019. Two reviewers extracted relevant data and assessed risk of bias independently. All English studies reporting any prevalence and/or AMR data of bacterial middle ear isolates from children with AOMd were included. Risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal checklist.
RESULTS
Of 4088 unique records retrieved, 19 studies (10,560 children) were included. Overall quality was judged good. Streptococcus pneumoniae (median 26.1%, range 9.1%-47.9%), Haemophilus influenzae (median 18.8%, range 3.9%-55.3%), Staphylococcus aureus (median 12.3%, range 2.3%-34.9%) and Streptococcus pyogenes (median 11.8%, range 1.0%-30.9%) were the most prevalent bacteria. In 76.0% (median, range 48.7%-100.0%, 19 studies, 1,429 children) any bacterium was identified. AMR data were sparse and mainly limited to S. pneumoniae. We found no evidence of a clear shift in the prevalence of bacteria and AMR over time.
CONCLUSIONS
In children with AOMd, S. pneumoniae and H. influenzae are the 2 predominant bacteria, followed by S. aureus and S. pyogenes in the post-PCV era. AMR data are sparse and no clearly change over time was observed. Ongoing surveillance of the microbiology profile in children with AOMd is warranted to guide antibiotic selection and to assess the impact of children's PCV status.
Topics: Acute Disease; Adolescent; Child; Child, Preschool; Drug Resistance, Bacterial; Haemophilus influenzae; Humans; Infant; Otitis Media; Pneumococcal Vaccines; Staphylococcus aureus; Streptococcus pneumoniae; Streptococcus pyogenes; Tympanic Membrane Perforation; Vaccines, Conjugate
PubMed: 34166300
DOI: 10.1097/INF.0000000000003134 -
Human Vaccines & Immunotherapeutics Oct 2021The aim was to summarize pneumococcal disease burden data among adults in Southern Europe and the potential impact of vaccines on epidemiology. Of 4779 identified... (Meta-Analysis)
Meta-Analysis
The aim was to summarize pneumococcal disease burden data among adults in Southern Europe and the potential impact of vaccines on epidemiology. Of 4779 identified studies, 272 were selected. Invasive pneumococcal disease (IPD) incidence was 15.08 (95% CI 11.01-20.65) in Spain versus 2.56 (95% CI 1.54-4.24) per 100,000 population in Italy. Pneumococcal pneumonia incidence was 19.59 (95% CI 10.74-35.74) in Spain versus 2.19 (95% CI 1.36-3.54) per 100,000 population in Italy. Analysis of IPD incidence in Spain comparing pre-and post- PCV7 and PCV13 periods unveiled a declining trend in vaccine-type IPD incidence (larger and statistically significant for the elderly), suggesting indirect effects of childhood vaccination programme. Data from Portugal, Greece and, to a lesser extent, Italy were sparse, thus improved surveillance is needed. Pneumococcal vaccination uptake, particularly among the elderly and adults with chronic and immunosuppressing conditions, should be improved, including shift to a higher-valency pneumococcal conjugate vaccine when available.
Topics: Adult; Aged; Europe; Greece; Humans; Incidence; Infant; Italy; Pneumococcal Infections; Pneumococcal Vaccines; Pneumonia, Pneumococcal; Portugal; Spain; Vaccines, Conjugate
PubMed: 34106040
DOI: 10.1080/21645515.2021.1923348 -
Pneumonia (Nathan Qld.) Apr 2021Prophylactic administration of antipyretics at the time of immunization seems to decrease some side effects, however reduced immune responses have been reported in some... (Review)
Review
BACKGROUND
Prophylactic administration of antipyretics at the time of immunization seems to decrease some side effects, however reduced immune responses have been reported in some studies. This systematic review aimed to investigate the effect of prophylactic use of antipyretics on the immune response following administration of pneumococcal conjugate vaccines (PCVs).
METHODS
A systematic review of randomized controlled trials and observational studies concerning the immune response to PCVs after antipyretic administration was performed up to November 2020 in the electronic databases of Pubmed and Scopus.
RESULTS
Of the 3956 citations retrieved, a total of 5 randomized control trials including 2775 children were included in the review. Included studies were referred to PCV10 (3 studies), PCV7 and PCV13 (one study each). The prophylactic administration of paracetamol decreased the immune response to certain pneumococcal serotypes in all included studies. The effect was more evident following primary vaccination and with immediate administration of paracetamol. Despite the reductions in antibody geometric mean concentrations, a robust memory response was observed following the booster dose. Besides, antibody titers remained above protective levels in 88-100% of participants. The use of ibuprofen, that was evaluated in two studies, did not seem to affect the immunogenicity of PCVs .
CONCLUSION
Although the reviewed studies had significant heterogeneity in design, paracetamol administration seems to affect the immune response for certain serotypes. The clinical significance of reduced immunogenicity especially before booster dose needs further investigation.
PubMed: 33894782
DOI: 10.1186/s41479-021-00085-8 -
Human Vaccines & Immunotherapeutics Dec 2022In 2010, a 10-valent pneumococcal non-typeable protein D conjugate vaccine (PHiD-CV) was introduced in the Brazilian national immunization program; the 3 + 1 dose...
In 2010, a 10-valent pneumococcal non-typeable protein D conjugate vaccine (PHiD-CV) was introduced in the Brazilian national immunization program; the 3 + 1 dose schedule was replaced by a 2 + 1 dose schedule in 2016. This systematic review presents the latest published evidence (2015-2020) on the impact after 10-year use of PHiD-CV in Brazil from a total of 29 publications. Overall, the PHiD-CV program had a positive impact on the morbidity and mortality associated with invasive pneumococcal disease (IPD), pneumonia and acute otitis media (AOM) in children <5 years-old. A reduction in the vaccine-type invasive disease was observed in all-ages; suggesting indirect protection unvaccinated older children and adults. The occurrence of non-vaccine type disease was evidenced in some studies. Higher vaccination coverage is required at national and state level for sustained population impact. Given the change in the vaccination schedule and the dynamics of pneumococcal disease epidemiology, continuous surveillance is warranted.GSK Study identifier: HO-18-19438.
Topics: Adolescent; Brazil; Child; Child, Preschool; Humans; Infant; Otitis Media; Pneumococcal Infections; Pneumococcal Vaccines; Vaccination; Vaccines, Conjugate
PubMed: 33735585
DOI: 10.1080/21645515.2021.1879578