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BMC Infectious Diseases May 2024Noroviruses are the second leading cause of death in children under the age of 5 years old. They are responsible for 200 million cases of diarrhoea and 50,000 deaths in... (Meta-Analysis)
Meta-Analysis
Rotavirus vaccines in Africa and Norovirus genetic diversity in children aged 0 to 5 years old: a systematic review and meta-analysis : Rotavirus vaccines in Africa and Norovirus genetic diversity.
Noroviruses are the second leading cause of death in children under the age of 5 years old. They are responsible for 200 million cases of diarrhoea and 50,000 deaths in children through the word, mainly in low-income countries. The objective of this review was to assess how the prevalence and genetic diversity of noroviruses have been affected by the introduction of rotavirus vaccines in Africa. PubMed, Web of Science and Science Direct databases were searched for articles. All included studies were conducted in Africa in children aged 0 to 5 years old with gastroenteritis. STATA version 16.0 software was used to perform the meta-analysis. The method of Dersimonian and Laird, based on the random effects model, was used for the statistical analyses in order to estimate the pooled prevalence's at a 95% confidence interval (CI). Heterogeneity was assessed by Cochran's Q test using the I2 index. The funnel plot was used to assess study publication bias. A total of 521 studies were retrieved from the databases, and 19 were included in the meta-analysis. The pooled norovirus prevalence's for pre- and post-vaccination rotavirus studies were 15% (95 CI, 15-18) and 13% (95 CI, 09-17) respectively. GII was the predominant genogroup, with prevalence of 87.64% and 91.20% respectively for the pre- and post-vaccination studies. GII.4 was the most frequently detected genotype, with rates of 66.84% and 51.24% respectively for the pre- and post-vaccination studies. This meta-analysis indicates that rotavirus vaccination has not resulted in a decrease in norovirus infections in Africa.
Topics: Humans; Rotavirus Vaccines; Infant; Africa; Child, Preschool; Caliciviridae Infections; Norovirus; Rotavirus Infections; Genetic Variation; Gastroenteritis; Infant, Newborn; Prevalence; Rotavirus; Vaccination
PubMed: 38822241
DOI: 10.1186/s12879-024-09434-6 -
Frontiers in Immunology 2024This meta-analysis was performed to assess the prevalence and circulating strains of rotavirus (RV) among Chinese children under 5 years of age after the implantation of... (Meta-Analysis)
Meta-Analysis
BACKGROUND
This meta-analysis was performed to assess the prevalence and circulating strains of rotavirus (RV) among Chinese children under 5 years of age after the implantation of the RV vaccine.
MATERIAL AND METHODS
Studies published between 2019 and 2023, focused on RV-based diarrhea among children less than 5 years were systematically reviewed using PubMed, Embase, Web of Science, CNKI, Wanfang and SinoMed Data. We synthesized their findings to examine prevalence and genetic diversity of RV after the RV vaccine implementation using a fixed-effects or random-effects model.
RESULTS
Seventeen studies met the inclusion criteria for this meta-analysis. The overall prevalence of RV was found to be 19.00%. The highest infection rate was noted in children aged 12-23months (25.79%), followed by those aged 24-35 months (23.91%), and 6-11 months (22.08%). The serotype G9 emerged as the most predominant RV genotype, accounting for 85.48% of infections, followed by G2 (7.70%), G8 (5.74%), G1 (4.86%), and G3 (3.21%). The most common P type was P[8], representing 64.02% of RV cases. Among G-P combinations, G9P[8] was the most frequent, responsible for 78.46% of RV infections, succeeded by G8P[8] (31.22%) and G3P[8] (8.11%).
CONCLUSION
Despite the variation of serotypes observed in China, the G1, G2, G3, G8 and G9 serotypes accounted for most RV strains. The genetic diversity analysis highlights the dynamic nature of RV genotypes, necessitating ongoing surveillance to monitor changes in strain distribution and inform future vaccine strategies.
Topics: Humans; Rotavirus Infections; Rotavirus; China; Genetic Variation; Prevalence; Infant; Child, Preschool; Genotype; Rotavirus Vaccines; Male
PubMed: 38690265
DOI: 10.3389/fimmu.2024.1364429 -
The Lancet. Global Health Jun 2024Information on the causes of deaths from diarrhoea in children younger than 5 years is needed to design improved preventive and therapeutic approaches. We aimed to...
BACKGROUND
Information on the causes of deaths from diarrhoea in children younger than 5 years is needed to design improved preventive and therapeutic approaches. We aimed to conduct a systematic analysis of studies to report estimates of the causes of deaths from diarrhoea in children younger than 5 years at global and regional levels during 2000-21.
METHODS
For this systematic review and Bayesian multinomial analysis, we included 12 pathogens with the highest attributable incidence in the Global Enteric Multicenter Study. We searched PubMed, Scopus, Embase, Web of Science, Global Health Index Medicus, Global Health OVID, IndMed, Health Information Platform for the Americas (PLISA), Africa-Wide Information, and Cochrane Collaboration for articles published between Jan 1, 2000, and Dec 31, 2020, using the search terms "child", "hospital", "diarrhea", "diarrhoea", "dysentery", "rotavirus", "Escherichia coli", "salmonella", "shigella", "campylobacter", "Vibrio cholerae", "cryptosporidium", "norovirus", "astrovirus", "sapovirus", and "adenovirus". To be included, studies had to have a patient population of children younger than 5 years who were hospitalised for diarrhoea (at least 90% of study participants), at least a 12-month duration, reported prevalence in diarrhoeal stools of at least two of the 12 pathogens, all patients with diarrhoea being included at the study site or a systematic sample, at least 100 patients with diarrhoea, laboratory tests done on rectal swabs or stool samples, and standard laboratory methods (ie, quantitative PCR [qPCR] or non-qPCR). Studies published in any language were included. Studies were excluded if they were limited to nosocomial, chronic, antibiotic-associated, or outbreak diarrhoea or to a specific population (eg, only children with HIV or AIDS). Each article was independently reviewed by two researchers; a third arbitrated in case of disagreement. If both reviewers identified an exclusion criterion, the study was excluded. Data sought were summary estimates. Data on causes from published studies were adjusted when necessary to account for the poor sensitivity of non-qPCR methods and for attributable fraction based on quantification of pathogens in children who are ill or non-ill. The causes of deaths from diarrhoea were modelled on the causes of hospitalisations for diarrhoea. We separately modelled studies reporting causes of diarrhoea in children who were hospitalised in low-income and middle-income countries (LMICs) and in high-income countries (HICs).
FINDINGS
Of 74 282 papers identified in the initial database search, we included 138 studies (91 included data from LMICs and 47 included data from HICs) from 73 countries. We modelled estimates for 194 WHO member states (hereafter referred to as countries), including 42 HICs and 152 LMICs. We could attribute a cause to 1 003 448 (83·8%) of the estimated 1 197 044 global deaths from diarrhoea in children younger than 5 years in 2000 and 360 730 (81·3%) of the estimated 443 833 global deaths from diarrhoea in children younger than 5 years in 2021. The cause with the largest estimated global attribution was rotavirus; in LMICs, the proportion of deaths from diarrhoea due to rotavirus in children younger than 5 years appeared lower in 2021 (108 322 [24·4%] of 443 342, 95% uncertainty interval 21·6-29·5) than in 2000 (316 382 [26·5%] of 1 196 134, 25·7-28·5), but the 95% CIs overlapped. In 2000, the second largest estimated attribution was norovirus GII (95 817 [8·0%] of 1 196 134 in LMICs and 225 [24·7%] of 910 in HICs); in 2021, Shigella sp had the second largest estimated attribution in LMICs (36 082 [8·1%] of 443 342), but norovirus remained with the second largest estimated attribution in HICs (84 [17·1%] of 490).
INTERPRETATION
Our results indicate progress in the reduction of deaths from diarrhoea caused by 12 pathogens in children younger than 5 years in the past two decades. There is a need to increase efforts for prevention, including with rotavirus vaccine, and treatment to eliminate further deaths.
FUNDING
Bill & Melinda Gates Foundation via Johns Hopkins University and the University of Virginia.
Topics: Humans; Diarrhea; Bayes Theorem; Infant; Child, Preschool; Global Health; Cause of Death; Infant, Newborn
PubMed: 38648812
DOI: 10.1016/S2214-109X(24)00078-0 -
Viruses Feb 2024Human type A rotavirus (RV-A) is world-recognized as the major pathogen causing viral gastroenteritis in children under 5 years of age. The literature indicates a... (Review)
Review
Human type A rotavirus (RV-A) is world-recognized as the major pathogen causing viral gastroenteritis in children under 5 years of age. The literature indicates a substantial increase in the diversity of rotavirus strains across continents, especially in Africa, which can pose significant challenges including an increase of disease burden and a reduction of vaccines' effectiveness. However, few studies have mapped the variety of circulating virus strains in different regions, which may hamper decisions on epidemiological surveillance and preventive public health measures. Thus, our aim was to compile the most updated available evidence on the genetic profile of RV-A among children in Africa and determine the prevalence of different genotypes according to the geographical regions by means of a broad systematic review. Systematic searches were performed in PubMed, Scopus, Web of Science, and Scielo without language, time limits, or geographical restrictions within the African continent. We selected full-text peer-reviewed articles assessing the genetic profile (i.e., genotyping) of RV-A in children up to 5 years old in Africa. Overall, 682 records were retrieved, resulting in 75 studies included for evidence synthesis. These studies were published between 1999 and 2022, were conducted in 28 countries from the five African regions, and 48% of the studies were carried out for 24 months or more. Most studies (n = 55; 73.3%) evaluated RV-A cases before the introduction of the vaccines, while around 20% of studies (n = 13) presented data after the vaccine approval in each country. Only seven (9.3%) studies compared evidence from both periods (pre- and post-vaccine introduction). Genotyping methods to assess RV-A varied between RT-PCR, nested or multiplex RT-PCR, testing only the most common P and G-types. We observed G1 and P[8] to be the most prevalent strains in Africa, with values around 31% and 43%, respectively. Yet if all the genotypes with the following highest prevalence were added ((G1 + G2, G3, G9) and (P[8] + P[6], P[4])), these figures would represent 80% and 99% of the total prevalence. The combination G1P[8] was the most reported in the studies (around 22%). This review study demonstrated an increased strain diversity in the past two decades, which could represent a challenge to the efficacy of the current vaccine.
Topics: Child; Humans; Infant; Child, Preschool; Rotavirus; Rotavirus Infections; Prevalence; Genetic Profile; Rotavirus Vaccines; Africa; Genotype; Feces
PubMed: 38400019
DOI: 10.3390/v16020243 -
Vaccine Mar 2024Rotavirus is the leading cause of severe diarrhea in infants and young children. Live attenuated vaccines can lead to horizontal transmission with the risk of... (Review)
Review
BACKGROUND
Rotavirus is the leading cause of severe diarrhea in infants and young children. Live attenuated vaccines can lead to horizontal transmission with the risk of vaccine-derived disease in contacts. Transmission of pentavalent human-bovine reassortant rotavirus vaccine (RV5) strains leading to clinical disease was not well evaluated in the pivotal clinical trials, and only a few case reports have been described in the literature.
METHODS
We performed a systematic literature review to investigate secondary transmission of RV5 strains to unvaccinated subjects globally. We searched Embase, Medline for English papers, CNKI, Wan Fang for Chinese papers, and other resources (i.e., conference papers with full text) from January 2005 to June 2021. Eligibility criteria for inclusion were original articles based on non-interventional studies (case-control studies, cohort studies, cross-sectional studies) using RV5 strain transmission as outcomes. Other study or publication types were excluded, such as pre-clinical studies, interventional studies and case reports. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was used, and study quality was assessed using the Newcastle-Ottawa Scale (NOS) for cohort studies and the JBI checklist for cross-sectional studies to assess the risk of bias.
RESULTS
The search generated 2,089 articles in total. Seven articles met all inclusion criteria, including six cohort studies and one cross-sectional study. All studies underwent quality assessment and complied with the quality criteria of the NOS or JBI checklist, respectively. Overall, none of the seven studies identified RV5 vaccine-type transmission to an unvaccinated population, in either hospitals or nurseries under a close contact environment. One study reported that 1% of unvaccinated infants had gastrointestinal symptoms, but all symptoms were attributed to other clinical conditions.
CONCLUSIONS
We found no evidence of horizontal transmission of RV5 strains to unvaccinated infants in a context of a limited amount and the descriptive nature of the identified studies.
Topics: Infant; Child; Humans; Cattle; Animals; Child, Preschool; Rotavirus; Rotavirus Infections; Rotavirus Vaccines; Cross-Sectional Studies; Vaccines, Combined; Vaccines, Attenuated
PubMed: 38355319
DOI: 10.1016/j.vaccine.2024.01.083 -
Learning Health Systems Jan 2024Diarrhea is still a significant global public health problem. There are currently no systematic evaluation of the modeling areas and approaches to predict diarrheal...
INTRODUCTION
Diarrhea is still a significant global public health problem. There are currently no systematic evaluation of the modeling areas and approaches to predict diarrheal illness outcomes. This paper reviews existing research efforts in predictive modeling of infectious diarrheal illness in pediatric populations.
METHODS
We conducted a systematic review via a PubMed search for the period 1990-2021. A comprehensive search query was developed through an iterative process and literature on predictive modeling of diarrhea was retrieved. The following filters were applied to the search results: human subjects, English language, and children (birth to 18 years). We carried out a narrative synthesis of the included publications.
RESULTS
Our literature search returned 2671 articles. After manual evaluation, 38 of these articles were included in this review. The most common research topic among the studies were disease forecasts 14 (36.8%), vaccine-related predictions 9 (23.7%), and disease/pathogen detection 5 (13.2%). Majority of these studies were published between 2011 and 2020, 28 (73.7%). The most common technique used in the modeling was machine learning 12 (31.6%) with various algorithms used for the prediction tasks. With change in the landscape of diarrheal etiology after rotavirus vaccine introduction, many open areas (disease forecasts, disease detection, and strain dynamics) remain for pathogen-specific predictive models among etiological agents that have emerged as important. Additionally, the outcomes of diarrheal illness remain under researched. We also observed lack of consistency in the reporting of results of prediction models despite the available guidelines highlighting the need for common data standards and adherence to guidelines on reporting of predictive models for biomedical research.
CONCLUSIONS
Our review identified knowledge gaps and opportunities in predictive modeling for diarrheal illness, and limitations in existing attempts whilst advancing some precursory thoughts on how to address them, aiming to invigorate future research efforts in this sphere.
PubMed: 38249852
DOI: 10.1002/lrh2.10382 -
Infectious Diseases of Poverty Dec 2023Non-National Immunization Program (NIP) vaccines have played an important role in controlling vaccine-preventable diseases (VPDs) in China. However, these vaccines are... (Review)
Review
BACKGROUND
Non-National Immunization Program (NIP) vaccines have played an important role in controlling vaccine-preventable diseases (VPDs) in China. However, these vaccines are paid out of pocket and there is room to increase their coverage. We focused on four selected non-NIP vaccines in this study, namely Haemophilus influenzae type b (Hib) vaccine, human papillomavirus (HPV) vaccine, pneumococcal conjugate vaccine (PCV), and rotavirus vaccine. We aimed to conduct a scoping review of their vaccination rates and the major barriers faced by health systems, providers, and caregivers to increase coverage.
METHODS
We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR). We searched five English databases (PubMed, Web of Science, EMBASE, Scopus, and WHO IRIS) and four Chinese databases using the search strategy developed by the study team. Two independent reviewers screened, selected studies, and examined their quality. We summarized the non-NIP vaccine coverage data by vaccine and applied the 5A framework (Access, Affordability, Acceptance, Awareness, Activation) to chart and analyze barriers to increasing coverage.
RESULTS
A total of 28 articles were included in the analysis (nine pertaining to vaccine coverage, and another 19 reporting challenges of increasing uptake). Among the four selected vaccines, coverage for the Hib vaccine was the highest (54.9-55.9% for 1 dose or more from two meta-analyses) in 2016, while the coverage of the other three vaccines was lower than 30%. Eight of the nine included articles mentioned the regional disparity of coverage, which was lower in under-developing regions. For example, the three-dose Hib vaccination rate in eastern provinces was 38.1%, whereas the rate in central and western provinces was 34.3% and 26.2%, respectively in 2017. Within the 5A framework, acceptance, awareness, and affordability stood out as the most prominent themes. Among the 12 identified sub-themes, high prices, low vaccine awareness, concerns about vaccine safety and efficacy were the most cited barriers to increasing the uptake.
CONCLUSIONS
There is an urgent need to increase coverage of non-NIP vaccines and reduce disparities in access to these vaccines across regions. Concerted efforts from the government, the public, and society are required to tackle the barriers and challenges identified in this study, both on the demand and supply side, to ensure everybody has equal access to life-saving vaccines in China. Particularly, the government should take a prudent approach to gradually incorporate non-NIP vaccines into the NIP step by step, and make a prioritizing strategy based on key factors such as disease burden, financial resources, and market readiness, with special attention to high-risk populations and underdeveloped regions.
Topics: Humans; Vaccines; Vaccination; Immunization Programs; China; Cost of Illness
PubMed: 38062480
DOI: 10.1186/s40249-023-01150-8 -
The Journal of Infectious Diseases May 2024Even moderate differences in rotavirus vaccine effectiveness against nonvaccine genotypes may exert selective pressures on circulating rotaviruses. Whether this vaccine... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Even moderate differences in rotavirus vaccine effectiveness against nonvaccine genotypes may exert selective pressures on circulating rotaviruses. Whether this vaccine effect or natural temporal fluctuations underlie observed changes in genotype distributions is unclear.
METHODS
We systematically reviewed studies reporting rotavirus genotypes from children <5 years of age globally between 2005 and 2023. We compared rotavirus genotypes between vaccine-introducing and nonintroducing settings globally and by World Health Organization (WHO) region, calendar time, and time since vaccine introduction.
RESULTS
Crude pooling of genotype data from 361 studies indicated higher G2P[4], a nonvaccine genotype, prevalence in vaccine-introducing settings, both globally and by WHO region. This difference did not emerge when examining genotypes over time in the Americas, the only region with robust longitudinal data. Relative to nonintroducing settings, G2P[4] detections were more likely in settings with recent introduction (eg, 1-2 years postintroduction adjusted odds ratio [aOR], 4.39; 95% confidence interval [CI], 2.87-6.72) but were similarly likely in settings with more time elapsed since introduction, (eg, 7 or more years aOR, 1.62; 95% CI, .49-5.37).
CONCLUSIONS
When accounting for both regional and temporal trends, there was no substantial evidence of long-term vaccine-related selective pressures on circulating genotypes. Increased prevalence of G2P[4] may be transient after rotavirus vaccine introduction.
Topics: Rotavirus Vaccines; Humans; Rotavirus; Rotavirus Infections; Genotype; Child, Preschool; Infant; Global Health; Vaccination
PubMed: 37738554
DOI: 10.1093/infdis/jiad403 -
Vaccine Aug 2023This systematic review presents cost-effectiveness studies of rotavirus vaccination in high-income settings based on dynamic transmission modelling to inform policy... (Review)
Review
PURPOSE
This systematic review presents cost-effectiveness studies of rotavirus vaccination in high-income settings based on dynamic transmission modelling to inform policy decisions about implementing rotavirus vaccination programmes.
METHODS
We searched CEA Registry, MEDLINE, Embase, Health Technology Assessment Database, Scopus, and the National Health Service Economic Evaluation Database for studies published since 2002. Full economic evaluation studies based on dynamic transmission models, focusing on high-income countries, live oral rotavirus vaccine and children ≤ 5 years of age were eligible for inclusion. Included studies were appraised for quality and risk of bias using the Consensus on Health Economic Criteria (CHEC) list and the Philips checklist. The review protocol was prospectively registered with PROSPERO (CRD42020208406).
RESULTS
A total of four economic evaluations were identified. Study settings included England and Wales, France, Norway, and the United States. All studies compared either pentavalent or monovalent rotavirus vaccines to no intervention. All studies were cost-utility analyses that reported incremental cost per quality-adjusted life year (QALY) gained. Included studies consistently concluded that rotavirus vaccination is cost-effective compared with no vaccination relative to the respective country's willingness to pay threshold when herd protection benefits are incorporated in the modelling framework.
CONCLUSIONS
Rotavirus vaccination was found to be cost-effective in all identified studies that used dynamic transmission models in high-income settings where child mortality rates due to rotavirus gastroenteritis are close to zero. Previous systematic reviews of economic evaluations considered mostly static models and had less conclusive findings than the current study. This review suggests that modelling choices influence cost-effectiveness results for rotavirus vaccination. Specifically, the review suggests that dynamic transmission models are more likely to account for the full impact of rotavirus vaccination than static models in cost-effectiveness analyses.
Topics: Child; Humans; Cost-Benefit Analysis; Rotavirus; State Medicine; Vaccination; Rotavirus Infections; Rotavirus Vaccines
PubMed: 37479614
DOI: 10.1016/j.vaccine.2023.06.064 -
Vaccine Mar 2023Immunization is an essential component of national health plans. However, the growing number of new vaccine introductions, vaccination campaigns and increasing... (Review)
Review
Immunization is an essential component of national health plans. However, the growing number of new vaccine introductions, vaccination campaigns and increasing administrative costs create logistic and financial challenges, especially in resource-limited settings. Sub-national geographic targeting of vaccination programs is a potential strategy for governments to reduce the impact of infectious disease outbreaks while optimizing resource allocation and reducing costs, promoting sustainability of critically important national immunization plans. We conducted a systematic review of peer-reviewed literature to identify studies that investigated the cost-effectiveness of geographically targeted sub-national vaccination programs, either through routine immunization or supplementary immunization activities. A total of 16 studies were included in our review, covering nine diseases of interest: cholera, dengue, enterotoxigenic Escherichia coli (ETEC), hepatitis A, Japanese encephalitis, measles, rotavirus, Shigella and typhoid fever. All studies modelled cost-effectiveness of geographically targeted vaccination. Despite the variation in study design, disease focus and country context, studies generally found that in countries where a heterogenous burden of disease exists, sub-national geographic targeting of vaccination programs in areas of high disease burden was more cost-effective than a non-targeted strategy. Sensitivity analysis revealed that cost-effectiveness was most sensitive to variations in vaccine price, vaccine efficacy, mortality rate, administrative and operational costs, discount rate, and treatment costs. This systematic review identified several key characteristics related to geographic targeting of vaccination, including the vaccination strategy used, variations in modelling parameters and their impact on cost-effectiveness. Additional research and guidance is needed to support the appropriateness and feasibility of geographically targeted vaccination and to determine what country context would make this a viable complement to routine immunization programs.
Topics: Cost-Benefit Analysis; Vaccination; Immunization Programs; Immunization; Vaccines
PubMed: 36781333
DOI: 10.1016/j.vaccine.2023.02.006