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Human Vaccines & Immunotherapeutics Nov 2016Antigenic drift of seasonal influenza viruses and the occasional introduction of influenza viruses of novel subtypes into the human population complicate the timely... (Review)
Review
Antigenic drift of seasonal influenza viruses and the occasional introduction of influenza viruses of novel subtypes into the human population complicate the timely production of effective vaccines that antigenically match the virus strains that cause epidemic or pandemic outbreaks. The development of game-changing vaccines that induce broadly protective immunity against a wide variety of influenza viruses is an unmet need, in which recombinant viral vectors may provide. Use of viral vectors allows the delivery of any influenza virus antigen, or derivative thereof, to the immune system, resulting in the optimal induction of virus-specific B- and T-cell responses against this antigen of choice. This systematic review discusses results obtained with vectored influenza virus vaccines and advantages and disadvantages of the currently available viral vectors.
Topics: Animals; Drug Carriers; Genetic Vectors; Humans; Influenza Vaccines; Vaccines, Attenuated; Vaccines, Synthetic; Viruses
PubMed: 27455345
DOI: 10.1080/21645515.2016.1210729 -
BMC Public Health Jun 2023Despite the human papillomavirus (HPV) vaccine being a safe, effective cancer prevention method, its uptake is suboptimal in the United States (U.S.). Previous research...
BACKGROUND
Despite the human papillomavirus (HPV) vaccine being a safe, effective cancer prevention method, its uptake is suboptimal in the United States (U.S.). Previous research has found a variety of intervention strategies (environmental and behavioral) to increase its uptake. The purpose of the study is to systematically review the literature on interventions that promote HPV vaccination from 2015 to 2020.
METHODS
We updated a systematic review of interventions to promote HPV vaccine uptake globally. We ran keyword searches in six bibliographic databases. Target audience, design, level of intervention, components and outcomes were abstracted from the full-text articles in Excel databases.
RESULTS
Of the 79 articles, most were conducted in the U.S. (72.2%) and in clinical (40.5%) or school settings (32.9%), and were directed at a single level (76.3%) of the socio-ecological model. Related to the intervention type, most were informational (n = 25, 31.6%) or patient-targeted decision support (n = 23, 29.1%). About 24% were multi-level interventions, with 16 (88.9%) combining two levels. Twenty-seven (33.8%) reported using theory in intervention development. Of those reporting HPV vaccine outcomes, post-intervention vaccine initiation ranged from 5% to 99.2%, while series completion ranged from 6.8% to 93.0%. Facilitators to implementation were the use of patient navigators and user-friendly resources, while barriers included costs, time to implement and difficulties of integrating interventions into the organizational workflow.
CONCLUSIONS
There is a strong need to expand the implementation of HPV-vaccine promotion interventions beyond education alone and at a single level of intervention. Development and evaluation of effective strategies and multi-level interventions may increase the uptake of the HPV vaccine among adolescents and young adults.
Topics: Adolescent; Young Adult; Humans; Papillomavirus Infections; Vaccination; Immunization; Cognition; Papillomavirus Vaccines
PubMed: 37386430
DOI: 10.1186/s12889-023-15876-5 -
International Journal of Infectious... Sep 2018For Ebola vaccine development, antibody response is a major endpoint although its determinants are not well known. We aimed to review Ebola vaccine studies and to assess... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
For Ebola vaccine development, antibody response is a major endpoint although its determinants are not well known. We aimed to review Ebola vaccine studies and to assess factors associated with antibody response variability in humans.
METHODS
We searched PubMed and Scopus for preventive Ebola vaccine studies in humans or non-human primates (NHP), published up to February 2018. For each vaccination group with Ebola Zaire antibody titre measurements after vaccination, data about antibody response and its potential determinants were extracted. A random-effects meta-regression was conducted including human groups with at least 8 individuals.
RESULTS
We reviewed 49 studies (202 vaccination groups including 74 human groups) with various vaccine platforms and antigen inserts. Mean antibody titre was slightly higher in NHP (3.10, 95% confidence interval [293; 327]) than in humans (2.75 [257; 293]). Vaccine platform (p<0·001) and viral strain used for antibody detection (p<0·001) were associated with antibody response in humans, but adjusted heterogeneity remained at 95%.
CONCLUSIONS
Various platforms have been evaluated in humans, including Ad26, Ad5, ChimpAd3, DNA, MVA, and VSV. In addition to platforms, viral strain used for antibody detection influences antibody response. However, variability remained mostly unexplained. Therefore, comparison of vaccine immunogenicity needs randomised controlled trials.
Topics: Animals; Antibodies, Viral; Clinical Studies as Topic; Ebola Vaccines; Ebolavirus; Hemorrhagic Fever, Ebola; Humans; Vaccination
PubMed: 29981944
DOI: 10.1016/j.ijid.2018.06.022 -
Nature Communications Mar 2023Vaccine protection from symptomatic SARS-CoV-2 infection has been shown to be strongly correlated with neutralising antibody titres; however, this has not yet been... (Meta-Analysis)
Meta-Analysis
Vaccine protection from symptomatic SARS-CoV-2 infection has been shown to be strongly correlated with neutralising antibody titres; however, this has not yet been demonstrated for severe COVID-19. To explore whether this relationship also holds for severe COVID-19, we performed a systematic search for studies reporting on protection against different SARS-CoV-2 clinical endpoints and extracted data from 15 studies. Since matched neutralising antibody titres were not available, we used the vaccine regimen, time since vaccination and variant of concern to predict corresponding neutralising antibody titres. We then compared the observed vaccine effectiveness reported in these studies to the protection predicted by a previously published model of the relationship between neutralising antibody titre and vaccine effectiveness against severe COVID-19. We find that predicted neutralising antibody titres are strongly correlated with observed vaccine effectiveness against symptomatic (Spearman [Formula: see text] = 0.95, p < 0.001) and severe (Spearman [Formula: see text] = 0.72, p < 0.001 for both) COVID-19 and that the loss of neutralising antibodies over time and to new variants are strongly predictive of observed vaccine protection against severe COVID-19.
Topics: Humans; Antibodies, Neutralizing; Antibodies, Viral; COVID-19; SARS-CoV-2; Vaccination; Vaccine Efficacy
PubMed: 36964146
DOI: 10.1038/s41467-023-37176-7 -
Journal of Infection and Public Health Mar 2023Globally, increasing coronavirus disease (COVID-19) vaccination coverage remains a major public health concern in the face of high rates of COVID-19 hesitancy among the... (Review)
Review
BACKGROUND
Globally, increasing coronavirus disease (COVID-19) vaccination coverage remains a major public health concern in the face of high rates of COVID-19 hesitancy among the general population. We must understand the impact of the determinants of COVID-19 vaccine uptake when designing national vaccination programmes. We aimed to synthesise nationwide evidence regarding COVID-19 infodemics and the demographic, psychological, and social predictors of COVID-19 vaccination uptake.
METHODS
We systematically searched seven databases between July 2021 and March 2022 to retrieve relevant articles published since COVID-19 was first reported on 31 December 2019 in Wuhan, China. Of the 12,502 peer-reviewed articles retrieved from the databases, 57 met the selection criteria and were included in this systematic review. We explored COVID-19 vaccine uptake determinants before and after the first COVID-19 vaccine roll-out by the Food and Drug Authority (FDA).
RESULTS
Increased COVID-19 vaccine uptake rates were associated with decreased hesitancy. Concerns about COVID-19 vaccine safety, negative side effects, rapid development of the COVID-19 vaccine, and uncertainty about vaccine effectiveness were associated with reluctance to be vaccinated. After the US FDA approval of COVID-19 vaccines, phobia of medical procedures such as vaccine injection and inadequate information about vaccines were the main determinants of COVID-19 vaccine hesitancy.
CONCLUSION
Addressing effectiveness and safety concerns regarding COVID-19 vaccines, as well as providing adequate information about vaccines and the impacts of pandemics, should be considered before implementation of any vaccination programme. Reassuring people about the safety of medical vaccination and using alternative procedures such as needle-free vaccination may help further increase vaccination uptake.
Topics: Humans; COVID-19 Vaccines; COVID-19; Vaccination; Vaccination Coverage; China; Vaccines
PubMed: 36738689
DOI: 10.1016/j.jiph.2023.01.020 -
Clinical Infectious Diseases : An... Sep 2022Rare cases of thrombosis and thrombocytopenia (thrombosis with thrombocytopenia syndrome [TTS]) have been associated with 2 coronavirus disease 2019 adenovirus vector... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Rare cases of thrombosis and thrombocytopenia (thrombosis with thrombocytopenia syndrome [TTS]) have been associated with 2 coronavirus disease 2019 adenovirus vector vaccines: the ChAdOx1 nCoV-19 Vaxzevria vaccine (Oxford/AstraZeneca) and the JNJ-7836735 Johnson & Johnson vaccine (Janssen). It is unknown if TTS is a class-mediated effect of adenovirus-based vaccines or if it could worsen known hypercoagulable states. Since most cases of TTS happen in women of childbearing age, pregnancy is a crucial risk factor to assess. Understanding these risks is important for advising vaccine recipients and future adenovirus vector vaccine development.
METHODS
To explore the potential associations of adenovirus-based vaccine components with symptoms of TTS in the general clinical trial population and in pregnant women in clinical trials, we conducted a systematic review and meta-analysis of adenovirus-based vector vaccines to document cases of thrombocytopenia, coagulopathy, and or pregnancy from 1 January 1966 to 9 August 2021.
RESULTS
We found 167 articles from 159 studies of adenovirus vector-based vaccines, 123 of which targeted infectious diseases. In the general population, 20 studies reported an event of thrombocytopenia and 20 studies indicated some coagulopathy. Among pregnant women, of the 28 studies that reported a total of 1731 pregnant women, thrombocytopenia or coagulopathy were not reported.
CONCLUSIONS
In this systematic review and meta-analysis, there was no class-wide effect of adenovirus vector vaccines toward thrombocytopenia or coagulopathy events in the general population or in pregnant women.
Topics: Adenoviridae; Adenovirus Vaccines; COVID-19; ChAdOx1 nCoV-19; Female; Humans; Pregnancy; Thrombocytopenia; Thrombosis; Vaccines
PubMed: 35134164
DOI: 10.1093/cid/ciac080 -
Vaccine Apr 2022Vaccinations are essential for preventing infectious diseases in children with chronic diseases as they have increased risk of infection from frequent use of biologics.... (Meta-Analysis)
Meta-Analysis Review
UNLABELLED
Vaccinations are essential for preventing infectious diseases in children with chronic diseases as they have increased risk of infection from frequent use of biologics. Response to immunizations in this group is not well known.
OBJECTIVE
A systematic review was performed to evaluate three primary outcomes: efficacy; immunogenicity; and safety of vaccines in children with chronic conditions treated with biologics.
METHODS
The protocol for our systematic review and meta-analysis was registered and published with PROSPERO. We searched electronic bibliographic databases for studies published from 2009 to 2019, focusing on vaccinations in children with chronic conditions treated with biologics.
RESULTS
We retrieved 532 records. Thirty-one full-text articles were selected, and 14 were included in the meta-analysis. No significant publication bias was found.
EFFICACY
limited data are available regarding the efficacy of vaccination, as most studies have focused on immunogenicity as surrogate outcome for efficacy. Immunogenicity: patients receiving anti-TNF-alpha therapy had a statistically significant risk of poor seroconversion (p = 0.028) and seroprotection by the serotype B influenza vaccine [inflammatory bowel disease (IBD) p = 0.013; juvenile idiopathic arthritis (JIA) p = 0.004]. We found adequate responses with H1N1 and H3N2 serotypes. Few studies existed for pneumococcal, hepatitis A virus, hepatitis B virus, varicella-zoster virus, Measles Mumps Rubella virus, and multiple vaccine administration.
SAFETY
vaccine administration was not associated with serious side effects, but JIA patients on anti-TNF alpha therapy had a statistically significant risk of presenting with myalgia or arthralgia postinfluenza vaccine (p = 0.014).
CONCLUSIONS
More evidence concerning efficacy, immunogenicity, and safety of vaccinations is needed to guide physicians in the vaccine decision process for this pediatric population.
Topics: Biological Products; Child; Humans; Immunogenicity, Vaccine; Influenza A Virus, H1N1 Subtype; Influenza A Virus, H3N2 Subtype; Measles-Mumps-Rubella Vaccine; Pneumococcal Vaccines; Tumor Necrosis Factor Inhibitors
PubMed: 35370019
DOI: 10.1016/j.vaccine.2022.03.041 -
Public Health Nov 2022Patients with cancer are more vulnerable to COVID-19 morbidity and morbidity than the general population and have been prioritised in COVID-19 vaccination programmes.... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
Patients with cancer are more vulnerable to COVID-19 morbidity and morbidity than the general population and have been prioritised in COVID-19 vaccination programmes. This study aims to investigate COVID-19 vaccine acceptance and hesitancy among patients with cancer.
STUDY DESIGN
This was a systematic review and meta-analysis.
METHODS
PubMed, ScienceDirect and the Cochrane COVID-19 study registry were searched in addition to secondary literature using a predefined search method. Two authors independently performed the study identification, screening and eligibility assessment. This study followed the Preferred Reporting Items for Systematic reviews and Meta-Analyses 2020 guidelines and Joanna Brides' Institute quality appraisal tools.
RESULTS
A total of 29 studies and reports were selected for the final review. The pooled prevalence of vaccine acceptance was 59% (95% confidence interval 52-67%, I: 99%). Concerns about vaccine-related side-effects, uncertainty about vaccine efficacy and safety, ongoing active anticancer therapies and scepticism about rapid vaccine development were the leading causes for vaccine hesitancy. Female gender and undergoing active anticancer treatments were significant factors associated with COVID-19 vaccine hesitancy. Early cancer stages (stages I and II) and good compliance with prior influenza vaccinations were significant factors associated with the acceptance of the COVID-19 vaccine.
CONCLUSIONS
Many patients with cancer are hesitant about COVID-19 vaccination. Well-designed problem-based educational interventions will increase compliance with COVID-19 vaccination.
Topics: Humans; Female; COVID-19 Vaccines; COVID-19; Vaccination Refusal; Vaccination; Vaccines; Neoplasms
PubMed: 36244261
DOI: 10.1016/j.puhe.2022.09.001 -
Vaccine May 2017Simpler schedules for human papillomavirus (HPV) vaccine delivery could improve vaccine coverage and the effectiveness of cervical cancer prevention. The objective of... (Meta-Analysis)
Meta-Analysis Review
Simpler schedules for human papillomavirus (HPV) vaccine delivery could improve vaccine coverage and the effectiveness of cervical cancer prevention. The objective of this study was to systematically review evidence about the effects of two-dose compared with three-dose schedules for human papillomavirus (HPV) vaccine and to describe the uptake of two-dose HPV vaccination schedules globally. We searched PubMed, the Cochrane Central Registry of Controlled Trials, trials registers, and manufacturers' databases from their earliest date to February 2016. We selected randomised controlled trials and controlled clinical trials that directly compared HPV vaccine schedules with two or three doses. We extracted data on immunological and clinical outcomes and used meta-analysis where appropriate. We also described the use of two-dose HPV vaccine schedules globally. We screened 1464 items and included seven eligible noninferiority trials in 11 countries. In randomised comparisons amongst adolescent girls (three trials), geometric mean concentrations (GMC) of antibodies against HPV16 and HPV18 were non-inferior or inconclusive, up to 24months after a two-dose compared with a three-dose schedule. One trial with a clinical outcome found no persistent HPV infections occurred after either two or three doses. In non-randomised comparisons, GMC were non-inferior or superior in adolescent girls receiving the two-dose schedule compared with women receiving the three-dose schedule for at least 21months after vaccination. By February 2017, 23 low and middle income and 25 high income countries had adopted a two-dose HPV vaccination schedule. A two-dose HPV vaccine schedule provides satisfactory immunological outcomes in adolescent girls, but uptake globally is limited, particularly in countries with the highest burden of cervical cancer.
Topics: Adolescent; Adult; Antibodies, Viral; Clinical Trials as Topic; Female; Human Papillomavirus Recombinant Vaccine Quadrivalent, Types 6, 11, 16, 18; Humans; Immunization Schedule; Papillomaviridae; Papillomavirus Infections; Papillomavirus Vaccines; Uterine Cervical Neoplasms; Vaccination; Vaccine Potency; Young Adult
PubMed: 28455170
DOI: 10.1016/j.vaccine.2017.03.096 -
Vaccine Apr 2018SYSVAC is an online bibliographic database of systematic reviews and systematic review protocols on vaccines and immunisation compiled by the London School of Hygiene &... (Review)
Review
INTRODUCTION
SYSVAC is an online bibliographic database of systematic reviews and systematic review protocols on vaccines and immunisation compiled by the London School of Hygiene & Tropical Medicine and hosted by the World Health Organization (WHO) through their National Immunization Technical Advisory Groups (NITAG) resource centre (www.nitag-resource.org). Here the development of the database and a bibliometric review of its content is presented, describing trends in the publication of policy-relevant systematic reviews on vaccines and immunisation from 2008 to 2016.
MATERIALS AND METHODS
Searches were conducted in seven scientific databases according to a standardized search protocol, initially in 2014 with the most recent update in January 2017. Abstracts and titles were screened according to specific inclusion criteria. All included publications were coded into relevant categories based on a standardized protocol and subsequently analysed to look at trends in time, topic, area of focus, population and geographic location.
RESULTS
After screening for inclusion criteria, 1285 systematic reviews were included in the database. While in 2008 there were only 34 systematic reviews on a vaccine-related topic, this increased to 322 in 2016. The most frequent pathogens/diseases studied were influenza, human papillomavirus and pneumococcus. There were several areas of duplication and overlap.
DISCUSSION
As more systematic reviews are published it becomes increasingly time-consuming for decision-makers to identify relevant information among the ever-increasing volume available. The risk of duplication also increases, particularly given the current lack of coordination of systematic reviews on vaccine-related questions, both in terms of their commissioning and their execution. The SYSVAC database offers an accessible catalogue of vaccine-relevant systematic reviews with, where possible access or a link to the full-text.
CONCLUSIONS
SYSVAC provides a freely searchable platform to identify existing vaccine-policy-relevant systematic reviews. Systematic reviews will need to be assessed adequately for each specific question and quality.
Topics: Bibliometrics; Evidence-Based Medicine; Humans; Immunization; London; Vaccination; Vaccines
PubMed: 29576305
DOI: 10.1016/j.vaccine.2018.02.049