Hepatitis B vaccination and the putative risk of central demyelinating diseases – A systematic review and meta-analysis

BackgroundThe anti-hepatitis B immunization campaigns launched in the early 1990s were a major public health breakthrough and targeted various populations (at-risk adults, newborns, adolescents). However, debate is still active about a possible link between this vaccine and central demyelination. This study provides a pooled estimate of this risk based on a comprehensive review and meta-analysis of all available epidemiologic studies.MethodsA systematic review was conducted in Medline, Embase, ISI Web of Science and the Cochrane Library from database inception to 10 May 2017. Grey literature was searched and snowballing was also undertaken. Only observational studies including a control group were retained. Primary outcome was multiple sclerosis diagnosed by recognized criteria. Study selection was performed by two independent reviewers with disagreements solved through discussion. This meta-analysis based on crude, adjusted estimates, or risks limited to the 3 months following immunization was performed using a generic inverse variance random-effect model. Heterogeneity was investigated; sensitivity and subgroup analyses were performed when necessary. This study followed the PRISMA statement and the MOOSE reporting guideline (Study protocol registered in PROSPERO: CRD42015020808).FindingsOf the 2804 references reviewed, 13 studies with a control group were analysed. None of the pooled risk estimates for either multiple sclerosis or central demyelination following HB immunization reached statistical significance. When considering adjusted risk ratios, the following non-significant figures were obtained: 1.19 (95%CI: 0.93 – 1.52) and 1.25 (95%CI: 0.97 – 1.62), for multiple sclerosis and central demyelination, respectively.ConclusionsNo evidence of an association between hepatitis B vaccination and central demyelination was found.     

Systematic review of economic evaluation studies: Are vaccination programs efficient in Spain?

Introduction

During the twentieth century, vaccination has been one of the measures of greatest public health impact. Vaccine administration has helped reduce the burden of disease and mortality from infectious diseases. At present, there is increasing concern about infectious diseases and the ability of health systems to control them, highlighting the need for evaluation of vaccination programs. The aim of this study was to conduct a systematic review of economic evaluation studies carried out regarding Spain on vaccines.

Methods

Systematic review. Search of articles in major bibliographic databases available online from January 1983 to June 2011. References identified were limited to full economic evaluations carried out regarding Spain that evaluated vaccination programs. For each of the selected papers, a set of predefined variables were extracted.

Results

A total of 46 studies met inclusion criteria. The topics studied were pneumococcal vaccination, influenza vaccination, Hepatitis B vaccination and varicella vaccination. Cost-minimization analysis, perspective of society, long time horizon, use of modeling techniques, and the inclusion of direct and indirect costs were the most common methodological characteristics. The results of the studies reviewed showed, in most cases, net savings or cost-effectiveness ratios below €30,000/QALY.

Conclusions

Although there has been an improvement in the methodological quality of studies, they still show shortcomings that should be addressed. From a public health perspective, it would be relevant to evaluate vaccines targeted to major health problems in Spain, including all relevant costs and benefits. In order to obtain a more efficient use of health resources, economic evaluation methods should be applied more rigorously and results should be used consistently in decision-making processes.     

Pertussis vaccine effectiveness and duration of protection – A systematic review and meta-analysis

A comprehensive review of observational pertussis vaccine effectiveness (VE) studies is needed to update gaps from previous reviews. We conducted a systematic review of VE and duration of protection studies for the whole-cell (wP) and acellular (aP) pertussis vaccines and conducted a formal meta-analysis using random effects models. Evidence continues to suggest that receipt of any pertussis vaccine confers protection in the short-term against disease although this protection wanes rapidly for aP vaccine. We detected significant heterogeneity in pooled estimates due, in part, to factors such as bias and confounding which may be mitigated by study design. Our review of possible sources of heterogeneity may help interpretation of other VE studies and aid design decisions in future pertussis VE research.     

Systematic review of economic evaluations of vaccination programs in mainland China: Are they sufficient to inform decision making?

The purpose of the study was to systematically review economic evaluations of vaccine programs conducted in mainland China. We searched for economic evaluations of vaccination in China published prior to August 3, 2015 in eight English-language and three Chinese-language databases. Each article was appraised against the 19-item Consensus on Health Economic Criteria list (CHEC-list). We found 23 papers evaluating vaccines against hepatitis B (8 articles), Streptococcus pneumoniae (5 articles), human papillomavirus (3 articles), Japanese encephalitis (2 articles), rotavirus (2 articles), hepatitis A (1 article), Enterovirus 71 (1 article) and influenza (1 article). Studies conformed to a mean of 12 (range: 6–18) items in the CHEC-list criteria. Five of six Chinese-language articles conformed to fewer than half of the 19 criteria items. The main criteria that studies failed to conform to included: inappropriate measurement (20 articles) and valuation (18 articles) of treatment and/or vaccination costs, no discussion about distributional implications (18 articles), missing major health outcomes (14 articles), no discussion about generalizability to other contexts (14 articles), and inadequate sensitivity analysis (13 articles). In addition, ten studies did not include major cost components of vaccination programs, and nine did not report outcomes in terms of life years even in cases where QALYs or DALYs were calculated. Only 13 studies adopted a societal perspective for analysis. All studies concluded that the appraised vaccination programs were cost-effective except for one evaluation of universal 7-valent pneumococcal conjugate vaccine (PCV-7) in children. However, three of the five studies on PCV-7 showed poor overall quality, and the number of studies on vaccines other than hepatitis B vaccine and PCV-7 was limited. In conclusion, major methodological flaws and reporting problems exist in current economic evaluations of vaccination programs in China. Local guidelines for good practice and reporting, institutional mechanisms and education may help to improve the overall quality of these evaluations.     

Vasculitis as an adverse event following immunization – Systematic literature review

BackgroundSeveral types of vasculitis have been observed and reported in temporal association with the administration of various vaccines. A systematic review of current evidence is lacking.ObjectiveThis systematic literature review aimed to assess available evidence and current reporting practice of vasculitides as adverse events following immunization (AEFI).MethodsWe reviewed the literature from 1st January 1994 to 30th June 2014. This review comprises randomized controlled trials, observational studies, case series, case reports, reviews and comments regardless of vaccine and target population.ResultsThe initial search resulted in the identification of 6656 articles. Of these, 157 articles were assessed for eligibility and 75 studies were considered for analysis, including 6 retrospective/observational studies, 2 randomized controlled trials, 7 reviews, 11 case series, 46 case reports and 3 comments. Most of the larger, higher quality studies found no causal association between vaccination and subsequent development of vasculitis, including several studies on Kawasaki disease and Henoch-Schönlein purpura (IgA vasculitis). Smaller case series reported a few cases of vasculitis following BCG and vaccines against influenza and hepatitis. Only 24% of the articles reported using a case definition of vasculitis.ConclusionsExisting literature does not allow establishing a causative link between vaccination and vasculitides. Further investigations were strengthened by the use of standardized case definitions and methods for data collection, analysis and presentation to improve data comparability and interpretation of vasculitis cases following immunization.     

Interventions to increase influenza vaccination rates in children with high-risk conditions—A systematic review

BackgroundInfluenza is a common cause of morbidity and mortality, especially among the elderly and those with certain chronic diseases. Annual influenza vaccination is recommended for individuals in at-risk groups, but rates of vaccination are particularly low in children with high-risk conditions (HRCs).ObjectiveTo conduct a systematic review of studies that have examined interventions aimed at improving influenza vaccination in children with HRCs.MethodsTwo databases – PubMed and SCOPUS – were searched (with no time or language restrictions) using a combination of keywords – Influenza AND vaccination OR immunization OR children AND asthma OR malignancy OR high-risk AND reminder. Duplicates were removed, and abstracts of relevant articles were screened using specific inclusion/exclusion criteria. Thirteen articles were selected, and five additional studies were identified following a review of the reference lists of the initial thirteen articles, bringing the total number to eighteen.ResultsMost studies were conducted in the United States. Among the 18 studies, there was one systematic review of a specific intervention in asthmatic children, seven randomized controlled trials (RCTs), six before-and-after studies, one non-randomized controlled trial, one retrospective cohort study, one quasi-experimental post-test study, and one letter to editors. Interventions reported include multi-component strategies, letter reminders, telephone recall, letters plus telephone calls, an asthma education tool and year-round scheduling for influenza vaccination, amongst others.ConclusionThere is good evidence that reminder letters will improve influenza vaccination uptake in children with HRCs, but the evidence that telephone recall or a combination of letter reminder and telephone recall will improve uptake is weak. It is not known if multiple reminder letters are more effective than single letters or if multi-component strategies are more effective than single or dual component strategies. There is a need for further research of these interventions, possibly outside the United States.     

Priming with MF59 adjuvanted versus nonadjuvanted seasonal influenza vaccines in children – A systematic review and a meta-analysis

BackgroundIdentifying optimal priming strategies for children <2 years could substantially improve the public health benefits of influenza vaccines. Adjuvanted seasonal influenza vaccines were designed to promote a better immune response among young vaccine-naïve children.MethodsWe systematically reviewed randomized trials to assess hemagglutination inhibition (HAI) antibody response to MF59-adjuvanted inactivated influenza vaccine (aIIV) versus nonadjuvanted IIV among children. We estimated pooled ratios of post-vaccination HAI geometric mean titer (GMT) for aIIV versus IIV and confidence intervals (CIs) using the pooled variances derived from reported CIs.ResultsMean age was 28 months (range, 6–72 months). Children received vaccines with either 7.5 μg (6–35 months) or 15 μg (≥36 months) hemagglutinin of each strain depending on age. Seven of eight trials administered trivalent vaccines and one used quadrivalent vaccine. Pooled post-vaccination GMT ratios against the three influenza vaccine strains were 2.5–3.5 fold higher after 2-dose-aIIV versus 2-dose-IIV among children 6–72 months, and point estimates were higher among children 6–35 months compared with older children. When comparing 1-dose-aIIV to 2-dose-IIV doses, pooled GMT ratios were not significantly different against A/H1N1 (1.0; 95% CI: 0.5–1.8; p = 0.90) and A/H3N2 viruses (1.0; 95% CI: 0.7–1.5; p = 0.81) and were significantly lower against B viruses (0.6; 95% CI: 0.4–0.8; p < 0.001) for both age groups. Notably, GMT ratios for vaccine-mismatched heterologous viruses after 2-dose-aIIV compared with 2-dose-IIV were higher against A/H1N1 (2.0; 95% CI: 1.1–3.4), A/H3N2 (2.9; 95% CI: 1.9–4.2), and B-lineage viruses (2.1; 95% CI: 1.8–2.6).ConclusionsTwo doses of adjuvanted IIV consistently induced better humoral immune responses against Type A and B influenza viruses compared with nonadjuvanted IIVs in young children, particularly among those 6–35 months. One adjuvanted IIV dose had a similar response to two nonadjuvanted IIV doses against Type A influenza viruses. Longer-term benefits from imprinting and cell-mediated immunity, including trials of clinical efficacy, are gaps that warrant investigation.     

Systematic Review of the Prevalence and Incidence of Parkinson’s Disease in Asia

Background

Parkinson’s disease (PD) is a common neurodegenerative disorder in older people, and half of the world’s older population lives in Asia. However, the epidemiology of PD in Asian countries is poorly understood. This review assembles evidence on the prevalence and incidence of PD in Asian countries and identifies gaps in our present knowledge.

Methods

A systematic search of studies published from 1965 to October 2008 was conducted using MEDLINE and EMBASE. The selection criteria were defined a priori. Prevalence and incidence were standardized to the WHO World Standard Population 2000. Twenty-one original studies were selected for the review. Two studies that described the ethnic origin of participants and contained Asian populations were also included in the analysis.

Results

Excluding one study with questionably low prevalence and incidence, the remaining studies reported a standardized all-age prevalence of 51.3 to 176.9 per 100 000 in door-to-door surveys; prevalence in record-based studies ranged from 35.8 to 68.3 per 100 000. The standardized incidence rates were 8.7 per 100 000 person-years in door-to-door surveys and 6.7 to 8.3 per 100 000 person-years in record-based surveys.

Conclusions

The prevalence of PD in Asian countries was slightly lower than that in Western countries. However, comparison of incidence was difficult because of the small number of studies. Varying methodologies, diagnostic criteria, and case-finding strategies contributed to the considerable variation in the reported prevalence and incidence of PD.Key words: epidemiology, prevalence, incidence, Parkinson’s disease, Asia     

Does bruxism impact the quality of life of children and adolescents? A systematic review and meta-analysis

Background

This study evaluated the impact of bruxism on the quality of life of children and adolescents.

Methods

Electronic searches were performed in the PubMed (Medline), Scopus, Web of Science, Lilacs, Cochrane Library, and SIGLE databases. We included observational studies that evaluated general and/or oral health-related quality of life in children and adolescents, with and without bruxism. Methodological quality and risk of bias were evaluated using the Fowkes and Fulton tool. Two meta-analyses (MA) were performed. MA1 considered the mean score achieved by questionnaires, whilst MA2 considered the measure of association [odds ratio (OR)] between bruxism and quality of life.

Results

Seven studies were selected for qualitative synthesis. Three studies were selected for quantitative synthesis, which considered only oral health-related quality of life. In MA1 (three studies), the mean difference of the B-ECOHIS score was 2.12 (95% CI?=??0.095–4.377, p?=?0.061). MA2 (two studies) showed that bruxism is not associated with oral health-related quality of life in children and adolescents (OR?=?1.889, 95% CI?=?0.53–6.71, p?=?0.325).

Conclusion

Bruxism does not impact quality of life in children and adolescents. Further studies should consider other quality of life questionnaires to confirm the absence of association.

     

Intraseasonal waning immunity of seasonal influenza vaccine – A systematic review and meta-analysis

BackgroundRecently, studies have suggested that influenza antibody titers decline with time since vaccination. Duration of vaccine protection is an important factor to determine the optimal timing of vaccination.ObjectiveWe aimed to systematically evaluate the implication of waning immunity on the duration of seasonal influenza vaccine antibody response.MethodElectronic databases and clinical trial registries were systematically searched to identify phase III/IV randomized clinical trials evaluating the immunogenicity of seasonal influenza vaccines measured by hemagglutination inhibition assay in healthy individuals six months of age and older. Meta-analyses were conducted to compare adjuvanted and standard influenza vaccine responses with time since vaccination.Results1918 articles were identified, of which ten were included in qualitative synthesis and seven in quantitative analysis (children; n=3, older adults; n=4). All studies were deemed to be at low risk of bias, except one study deemed at high risk of bias due to missing outcome data. The majority of included studies found a rise in antibody titers at one-month followed by a decline at six-month post-vaccination. At six-months post-vaccination overall risk differences in seroprotection were significantly higher for children vaccinated with adjuvanted compared to standard vaccines (0.29; 95 % confidence interval (CI), 0.14–0.44). A small increase in seroprotection levels was observed among older adults vaccinated with an adjuvanted compared to standard vaccines, which remained constant over six-months (pre-vaccination: 0.03; 95 % CI, 0.00–0.09 and one- and six-months post-vaccination: 0.05; 95 % CI, 0.01–0.09).ConclusionsOur results found evidence of persistent antibody responses following influenza vaccination over the course of a typical influenza season. Even if influenza vaccine responses wane over a six-month period, vaccination likely still provides a significant advantage in protection, which may be enhanced with adjuvanted vaccines, particularly in children. Further research is needed to identify the exact timing when the decline in antibody response begins to better inform the optimal timing of influenza vaccination programs.Trial registration: PROSPERO (CRD42019138585).     

Knowledge,attitudes and practices related to influenza illness and vaccination in children: Role of awareness campaigns in changing parents’ attitudes toward influenza vaccination in Jordan

BackgroundInfluenza infection is associated with a significant health burden in children, especially in developing countries. The influenza vaccine is an important preventive strategy for flu illness. Aim of this study to assess knowledge, attitudes and practices (KAP) related to influenza illness and vaccination in children in the Jordanian population and to study the effect of awareness campaigns on changing the attitudes of parents toward vaccinating their children against influenza.MethodsA cross-sectional study was conducted among families visiting shopping malls and parks in November 2016. A questionnaire was administered via in-person interviews. Answers to KAP questions regarding influenza illness and vaccination were summed, with a total KAP score of 30. Facts about influenza illness and vaccination were explained to parents and provided in printed pamphlets.ResultsThere were 1241 respondents. 10.9% of participants had vaccinated their children during the last season 2015/2016. The mean KAP score (standard deviation) was 16.21 (4.61). People living in urban areas, with high monthly income >600 JD and healthcare workers had higher KAP scores than their counterparts. Compared to other sources of information about the influenza vaccine, health resources correlated most with vaccinating children. Awareness and educational pamphlets changed attitudes positively in 29% of parents who refused the influenza vaccine for their children.ConclusionsAwareness about influenza illness and vaccination is insufficient, and the coverage rate of influenza vaccination in children is low in the Jordanian population. Implementing public health policies is necessary to spread knowledge about influenza illness and vaccination and to promote the practice of receiving the influenza vaccine in children. Educational campaigns are helpful in changing the attitudes of parents toward vaccinating their children against the flu.     

Targeted vaccination in healthy school children – Can primary school vaccination alone control influenza?

BackgroundThe UK commenced an extension to the seasonal influenza vaccination policy in autumn 2014 that will eventually see all healthy children between the ages of 2–16 years offered annual influenza vaccination. Models suggest that the new policy will be both highly effective at reducing the burden of influenza as well as cost-effective. We explore whether targeting vaccination at either primary or secondary schools would be more effective and/or cost-effective than the current strategy.MethodsAn age-structured deterministic transmission dynamic SEIR-type mathematical model was used to simulate a national influenza outbreak in England. Costs including GP consultations, hospitalisations due to influenza and vaccinations were compared to potential gains in quality-adjusted life years achieved through vaccinating healthy children. Costs and benefits of the new JCVI vaccination policy were estimated over a single season, and compared to the hypothesised new policies of targeted and heterogeneous vaccination.Findings and conclusionAll potential vaccination policies were highly cost-effective. Influenza transmission can be eliminated for a particular season by vaccinating both primary and secondary school children, but not by vaccinating only one group. The most cost-effective policy overall is heterogeneous vaccination coverage with 48% uptake in primary schools and 34% in secondary schools. The Joint Committee on Vaccination and Immunisation can consider a modification to their policy of offering seasonal influenza vaccinations to all healthy children of ages 2–16 years.     

Systematic review with meta-analysis of partial enteral nutrition for the maintenance of remission in Crohn’s disease

Although enteral nutrition (EN) is effective for induction therapy in Crohn’s disease (CD), it remains unclear whether partial enteral nutrition (PEN), i.e., EN, along with a daily diet, is effective for maintenance therapy in CD. It was hypothesized that PEN would be effective as a maintenance therapy in CD. This meta-analysis aimed to evaluate the efficacy and safety of PEN for maintenance therapy in CD. PubMed, EMBASE, Web of Science, and Cochrane Library were searched up to January 2019 for eligible prospective controlled trials, and then a meta-analysis was conducted. The primary outcome was clinical relapse, as defined in the primary studies. Eight studies with 429 patients were included in the meta-analysis. The rate of clinical relapse at 0.5 to 2 years was significantly lower in patients receiving PEN (420-1800 kcal/d) than in those not receiving nutrition therapy (RR: 0.67, 95% CI: 0.54-0.82, P < .01; number needed to treat = 5, P < .01). Patients receiving PEN exhibited a higher frequency of clinical remission maintenance at 0.5 to 1 year (67%) than did those not receiving nutrition therapy (48%; RR: 1.32, 95% CI: 1.07-1.64, P = .01). The total adverse event rate was comparable in the two groups (RR: 3.60, 95% CI: 0.70-18.66, P = .13). PEN may be more effective than the absence of EN therapy for the maintenance of remission in CD with a good safety profile.     

Impact of influenza vaccination on healthcare utilization – A systematic review

IntroductionAlthough a vaccine-preventable disease, influenza causes approximately 3–5 million cases of severe illness and about 290,000–650,000 deaths worldwide, which occur primarily among people 65 years and older. Nonetheless, prevention of influenza and its complications rely mainly on vaccination. We aimed to systematically evaluate influenza vaccine effectiveness at reducing healthcare utilization in older adults, defined as the reduction of outpatient visits, ILI and influenza hospitalizations, utilization of antibiotics and cardiovascular events by vaccination status during the influenza season.MethodsWe searched MEDLINE, EMBASE, CINAHL, Cochrane Library and considered any seasonal influenza vaccine, excluding the pandemic (2009–10 season) vaccine. Reviewers independently assessed data extraction and quality assessment.ResultsOf the 8308 citations retrieved, 22 studies were included in the systematic review. Overall, two studies (9%) were deemed at moderate risk of bias, thirteen (59%) at serious risk of bias and seven (32%) at critical risk of bias. For outpatient visits, we found modest evidence of protection by the influenza vaccine. For all-cause hospitalization outcomes, we found a wide range of results, mostly deemed at serious risk of bias. The included studies suggested that the vaccine may protect older adults against influenza hospitalizations and cardiovascular events. No article meeting our inclusion criteria explored the use of antibiotics and ILI hospitalizations. The high heterogeneity between studies hindered the aggregation of data into a meta-analysis.ConclusionThe variability between studies prevented us from drawing a clear conclusion on the effectiveness of the influenza vaccine on healthcare utilization in older adults. Overall, the data suggests that the vaccine may result in a reduction of healthcare utilization in the older population. Further studies of higher quality are necessary.     

Childhood pneumococcal disease in Africa – A systematic review and meta-analysis of incidence,serotype distribution,and antimicrobial susceptibility

BackgroundDetermining the incidence, disease-associated serotypes and antimicrobial susceptibility of invasive pneumococcal disease (IPD) among children in Africa is essential in order to monitor the impact of these infections prior to widespread introduction of the pneumococcal conjugate vaccine (PCV).MethodsTo provide updated estimates of the incidence, serotype distribution, and antimicrobial susceptibility profile of Streptococcus pneumoniae causing disease in Africa, we performed a systematic review of articles published from 2000 to 2015 using Ovid Medline and Embase. We included prospective and surveillance studies that applied predefined diagnostic criteria. Meta-analysis for all pooled analyses was based on random-effects models.ResultsWe included 38 studies consisting of 386,880 participants in 21 countries over a total of 350,613 person-years. The pooled incidence of IPD was 62.6 (95% CI 16.9, 226.5) per 100,000 person-years, including meningitis which had a pooled incidence of 24.7 (95% CI 11.9, 51.6) per 100,000 person-years. The pooled prevalence of penicillin susceptibility was 78.1% (95% CI 61.9, 89.2). Cumulatively, PCV10 and PCV13 included 66.9% (95% CI 55.9, 76.7) and 80.6% (95% CI 66.3, 90.5) of IPD serotypes, respectively.ConclusionsOur study provides an integrated and robust summary of incidence data, serotype distribution and antimicrobial susceptibility for S. pneumoniae in children ≤5 years of age in Africa prior to widespread introduction of PCV on the continent. The heterogeneity of studies and wide range of incidence rates across the continent indicate that surveillance efforts should be intensified in all regions of Africa to improve the integrity of epidemiologic data, vaccine impact and cost benefit. Although the incidence of IPD in young children in Africa is substantial, currently available conjugate vaccines are estimated to cover the majority of invasive disease-causing pneumococcal serotypes. These data provide a reliable baseline from which to monitor the impact of the broad introduction of PCV.