Vaccines

The Bacillus Calmette-Guerin (BCG) vaccine, the only vaccine against tuberculosis, induces cross-protection against pathogens unrelated to Mycobacterium, including viruses. Epidemiological studies have identified potential benefits of BCG vaccination against SARS-CoV-2 infection. While BCGs heterologous effects have been widely attributable to trained immunity, we hypothesized BCG vaccination could induce cross-reactive antibodies against the spike protein of SARS-CoV-2 Wuhan-Hu-1. The concentration of IgG reactive to SARS-CoV-2 spike protein from the sera of BCG-vaccinated, Diversity Outbred (DO) mice and C57BL/6J inbred mice was measured using ELISA. Sera from 10/15 BCG-vaccinated DO mice possessed more IgG reactive to recombinant spike protein than sera from BCG-vaccinated C57BL/6J mice and unvaccinated DO mice. Amino acid sequences common to BCG cell wall/membrane proteins and SARS-CoV-2 spike protein were identified as potential antigen candidates for future study. These results imply a humoral mechanism, influenced by genotype, by which BCG vaccination could confer immunity to SARS-CoV-2. Graphic Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=80 SRC="FIGDIR/small/488640v1_ufig1.gif" ALT="Figure 1"> View larger version (23K): org.highwire.dtl.DTLVardef@1ff9d16org.highwire.dtl.DTLVardef@a2302dorg.highwire.dtl.DTLVardef@8ee2borg.highwire.dtl.DTLVardef@4c7b55_HPS_FORMAT_FIGEXP M_FIG C_FIG

BackgroundSince the beginning of the COVID-19 outbreak, many pharmaceutical companies were racing to develop a safe and effective COVID-19 vaccine. Simultaneously, rumors and misinformation about COVID-19 were and still widely spreading. Therefore, this study aimed to investigate the prevalence of COVID-19 misinformation among the Yemeni population and its association with vaccine acceptance and perceptions. MethodsA cross-sectional online survey was conducted in four major cities in Yemen. The constructed questionnaire consisted of four main sections (sociodemographic data, misinformation, perceptions (perceived susceptibility, severity and worry), and vaccination acceptance evaluation). Subject recruitment and data collection were conducted online utilizing social websites and using the snowball sampling technique. Descriptive and inferential analyses were performed using SPSS version 27. ResultsThe total number of respondents was 484. Over 60% of them were male and had a university education, more than half had less than 100$ monthly income and were Khat chewers, while only 18% were smokers. Misinformation prevalence ranged from 8.9% to 38.9%, depending on the statement being asked. Men, university education, higher income, employment, and living in urban areas were associated with a lower misinformation level (p <0.05). Statistically significant association (p <0.05) between university education, living in urban areas, and being employed with perceived susceptibility were observed. The acceptance rate was 61.2% for free vaccines, but it decreased to 43% if they had to purchase it. Females, respondents with lower monthly income, and those who believed that pharmaceutical companies made the virus for financial gains were more likely to reject the vaccination (p <0.05). ConclusionThe study revealed that the acceptance rate to take a vaccine was suboptimal and significantly affected by gender, misinformation, cost, and income. Furthermore, being female, Nonuniversity educated, low-income, and living in rural areas were associated with higher susceptibility to misinformation about COVID-19. These findings show a clear link between misinformation susceptibility and willingness to vaccinate. Focused awareness campaigns to decrease misinformation and emphasize the vaccinations safety and efficacy might be fundamental before initiating any mass vaccination in Yemen.

A number of COVID-19 vaccines are under development, with one or more possibly becoming available in 2021. We conducted a global survey in June 2020 of 13,426 people in 19 countries to determine potential acceptance rates of a COVID-19 vaccine and factors influencing acceptance. We ran univariate logistic regressions to examine the associations with demographic variables. 71.5% reported they would be very or somewhat likely to take a COVID-19 vaccine; 61.4% reported they would accept their employers recommendation to take a COVID-19 vaccine. Differences in acceptance across countries ranged from almost 9 in 10 (China) to fewer than 6 in 10 (Russia). Respondents reporting higher levels of trust in information from government sources were more likely to accept a vaccine, and take their employers advice to do so. Targeted interventions addressing age, sex, income, and education level are required to increase and sustain public acceptance of a COVID-19 vaccine.

The advent of vaccines against SARS-CoV-2 ushered in an unprecedented global response to COVID-19, with the largest and most ambitious mass vaccination campaign in human history. The scale of this effort means that safety signals suggesting adverse effects may only be detectable using passive reporting. This paper examines reports to the CDC/FDAs VAERS system in the first six months of 2021, using an empirical Bayesian model with a gamma Poisson shrinker to identify potential safety signals from COVID-19 vaccines currently on the U.S. market. Based on this preliminary data, it is concluded that the COVID-19 vaccines safety significantly exceeds that of previously marketed vaccines, and other than a known risk of thrombotic events, no safety signals of concern emerge.

Although various COVID-19 vaccines have shown efficacy against placebo in randomized clinical trials, no head-to-head comparisons are yet available. This study aims to compare the efficacy of available COVID-19 vaccines. Vaccine trials searched in May 2021 were included. Data were extracted from Kaplan-Meier (KM) curves using the WebPlotDigitizer program for the individual participant (IP) data simulation. A mixed-effect acceleration failure model with log-logistic and Weibull distributions was used to estimate relative effects for individual vaccines as well as grouped by class: inactivated virus, mRNA, and viral vector. Primary studies were considered as the random effect in the model. Hazard ratios (HR) were estimated and compared across vaccine groups. All vaccines were efficacious in lowering symptomatic infection compared to placebo. CoronaVac, Ad26.COV2.S, ChAdOx1 nCoV-19, rAd26/rAd5, WIV04, HB02, and BNT162b2 showed 7.61 (4.50, 12.87), 6.77 (4.08, 11.24), 5.01 (2.93, 8.57), 4.50 (2.52, 8.01), 3.90 (2.04, 7.45), 3.18 (1.62, 6.21), and 2.15 (1.22, 3.78) times significantly higher risk of infection than mRNA-1273. mRNA vaccines were the most efficacious vaccine group compared to inactivated virus and viral vectors with HRs (95% CI) of 0.27 (0.20, 0.37) and 0.28 (0.21, 0.37), respectively. Although all vaccines showed significant protection compared to no vaccination. mRNA vaccines, including mRNA-1273 and BNT162b2, showed the highest efficacy in preventing symptomatic COVID-19 infection. Simulated IP data from the KM curve might allow treatment comparison when there is no primary study comparing active treatments.

In the present study, three basic aspects related to COVID-19 are presented. O_LIThe occurrence of coronavirus infection is analyzed statistically as number of coronaviruses infected alveolar cells compared to normal alveolar cells in human lungs. The mole concept is used to estimate the number of normal alveolar cells per human lung. The number of coronavirus infections in infected alveolar cells is estimated from the published Lower Respiratory Tract (LRT) load data. The Poisson probability distribution is aptly applied to imply the incubation period of the coronavirus infection to be within day-3 to day-7, with the cumulative probability of 75%. The incubation period within day-0 to day-10 has a cumulative probability of 98%. It implies a 10-day quarantine to isolate an uninfected individual as a precautionary measure. C_LIO_LIThree vaccines to combat COVID-19, which adopt distinct paradigms while preparing them, are analyzed. These are Modernas mRNA-1273, Oxford-AstraZenecas ChAdOx1 nCoV-19 and Bharat BioTechs COVAXIN. The mole concept is used to estimate the antigen mass density per dose of each of these vaccines as 10 g cm-3, 0.1 g cm-3 and 1 g cm-3, respectively. The vaccines are deemed to be compatible to neutralize the infection. C_LIO_LIA statistical analysis is performed of the Modernas mRNA-1273 vaccine efficacy of 94.1% and Oxfords ChAdOx1 nCoV-19 vaccine efficacy of 62.1% in terms of groups of volunteers testing negative to vaccine by chance. In the Moderna vaccination testing scenario, since the probability of negative response of vaccine is small, the Poisson probability distribution for 95% cumulative probability is used to describe the vaccination testing in 300 samples of 47 volunteers each. Thus, 87% of samples have average group of 3 volunteers testing negative to vaccine. About 6% of samples have all volunteers testing positive to vaccine. In the Oxford vaccination testing scenario, since the probability of negative response of vaccine is finite, the Gaussian probability distribution for 95% probability is used to describe the vaccination testing in 75 samples of 120 volunteers each. Thus, 68% of samples have average group of 45 volunteers testing negative to vaccine. No sample has all volunteers testing positive to vaccine. A vaccine, irrespective of its efficacy being high or low, is necessary for mass immunization. C_LI

Background: COVID-19 vaccines have been rolled out recently in several parts of the world. Although the protective efficacy is frequently discussed, little is known about the real-world post-vaccination experience outside of clinical trial conditions. Knowledge about what to expect after vaccination will help educate the public, dispel misinformation and reduce vaccine hesitancy. Aim: 1. To assess the immediate response to the first dose of COVID-19 vaccine. 2. To study the spectrum of post-vaccination symptom profile for individual vaccines. Methods: A cross-sectional online survey was done which included questions pertaining to the immediate post vaccination experience in India. Results: A total of 5396 people responded to the survey over a one-week period from 29 January to 4 February. Overall, 65.9 % of respondents reported at least one post-vaccination symptom. Tiredness (45%), myalgia (44%), fever (34%), headache (28%), local pain at injection site (27%), joint pain (12%), nausea (8%) and diarrhea (3%) were the most prevalent symptoms. The chance of having symptoms decreased with advancing age. The frequency of symptoms was 81% (3rd decade or 20-29 years), 80% (4th decade or 30-39 years), 68% (5th decade), 58% (6th decade), 45% (7th decade), 34% (8th decade) and 7% (9th decade, 80-90 years). Post-vaccination symptoms were more likely to be reported by women (74.7%) compared to men (58.6%) (p &lt; 0.001). Among those who reported symptoms, 79% noticed them within the first 12 hours. 472 out of 5396 (8.7%) reported past history of COVID-19. Their symptom profile was not different to those who did not have a past history. Conclusions: Two-thirds of healthcare professionals who completed the survey reported mild and short-lived post-vaccination symptoms. Tiredness, myalgia and fever were most commonly reported. These symptoms were consistent with an immune response commonly associated with vaccines, and correlated with the findings from previously published phase 2/3 trials. In 90% cases, the symptoms were either milder than expected or meeting the expectation of the vaccine recipient. No serious events were reported. Symptoms were more common among younger individuals. There was no difference in symptoms among those who had a past history of COVID-19.

Patients with immune conditions and immune-modifying therapies were excluded from the Covid-19 vaccine trials. Studies have shown conflicting response to different vaccines in persons receiving immune suppressors or biologics. The aim of this study is to evaluate humoral and cellular response to Covid-19 vaccines in patients with Inflammatory Bowel Disease (IBD) using biologic and/or immunomodulatory (IMM) therapies. MethodsParticipants are adults with IBD receiving biologics or IMM planning to receive a Covid 19 vaccine. Cellular immunity (CD4+ and CD8+ T cell levels) with flow cytometry are measured at baseline and 2 weeks after each vaccine dose. Humoral immunity (antibody titers and neutralizing capacity,VNT%) is analyzed by ELISA at baseline, 2 weeks after each dose, and 6 and 12 months after vaccine. We present the early results of the first 19 subjects. The study is approved by the IRB. Results19 subjects (18 in biologics and 1 in IMM) who received 2 doses of the Pfizer-BioNTech vaccine are included. Total IgG antibodies increased 21.13 times after the first dose and 90 times after the second dose. VTN% increased 11.92 times after the first dose and 53.79 times after the second dose. When compared with a healthy control cohort, total IgG antibodies and VTN% were lower in the subjects after the first dose. After the second dose, IgG antibodies increased but remained lower than controls, but VTN% were similar to controls. CD4 and CD8 mean levels had an upward trend after vaccination. ConclusionsNeutralizing capacity response to the vaccine in subjects was similar to a healthy cohort in spite of lower increases in total IgG antibodies. The CD4 and CD8 results observed may support the capacity to mount an effective cellular response in patients on biologics. Larger studies are needed to determine vaccine efficacy in these patients.

BackgroundCOVID-19 vaccination is crucial for mitigating the pandemics impact. However, vaccine hesitancy and access challenges have hindered global vaccination efforts. This meta-analysis aimed to estimate the pooled COVID-19 vaccine uptake proportion and identify associated determinants in Cameroon. MethodsThis review, conducted according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, identified articles through searches of electronic databases, including PubMed, Scopus, Web of Science, ScienceDirect, and Google Scholar, as well as through gray literature. The search encompassed published and unpublished studies from 2021 to 2024 reporting on COVID-19 vaccine uptake and/or acceptance in Cameroon. Extracted data were compiled in a Microsoft Excel spreadsheet and analyzed using R statistical software (version 4.4.2). A random-effects model was employed when heterogeneity exceeded 50%. Publication bias was assessed using funnel plots, Eggers test, and Beggs test. Meta-regression was used to explore the influence of study characteristics. ResultsTwenty-two studies, encompassing 24,130 participants, were included. The pooled vaccine uptake proportion was 37.14% (95% CI: 29.24-45.05), with substantial heterogeneity (I{superscript 2} = 98.2%, p<0.001). Subgroup analyses revealed lower uptake among the general population (23.18%; 95% CI: 10.11-36.25) and in community settings (16.0%; 95% CI: 0.97-31.04) compared with healthcare workers (42.12%; 95% CI: 34.14-50.09). Younger age (OR = 0.53; 95% CI: 0.42-0.67) was inversely associated with vaccine uptake, while being in a partnership (OR = 1.59; 95% CI: 1.11-2.27) was positively associated. Higher levels of education (OR = 1.75; 95% CI: 1.56-1.97), urban residence (OR = 1.66; 95% CI: 1.21-2.29). ConclusionThis meta-analysis revealed a suboptimal pooled COVID-19 vaccine uptake required to ensure a herd immunity. The results of this meta-analysis underline the crucial need to step up efforts to improve vaccination coverage, particularly among the most vulnerable populations. Identifying and addressing the factors underlying this low coverage is imperative if public health objectives are to be met. Public health interventions should be tailored to address the specific concerns and needs of different age groups and marital statuses.

How do citizens choose COVID-19 vaccines, and when do they wish to be vaccinated? A choice-based conjoint experiment was fielded in Hong Kong to examine factors that shape citizens preference toward COVID-19 vaccines and their time preference to be vaccinated, which is overlooked in extant literature. Results suggest people are most concerned about vaccines efficacy and severe side-effects, and that cash incentives are not useful in enhancing vaccine appeal. The majority of respondents show low intention for immediate vaccination, and many of them want to delay their vaccination. Further analysis shows that their time preference is shaped more by respondent characteristics than vaccine attributes. In particular, confidence in the vaccine, trust in government, and working in high-risk professions are associated with earlier timing for vaccine uptake. Meanwhile, forced COVID testing would delay vaccination. The findings offer a novel view in understanding how people decide whether and when to receive new vaccines, which have pivotal implications for a head start of any mass vaccination programs. HighlightsO_LIPeople are most concerned about vaccines efficacy and severe side-effects when choosing COVID-19 vaccines C_LIO_LICash incentives are not useful in enhancing vaccines appeal C_LIO_LITime preference of vaccination is shaped more by respondent characteristics than vaccine attributes C_LIO_LIForced COVID testing might delay vaccination decision C_LI

Four principal types of authorised COVID-19 vaccines include inactivated whole-virus vaccines, protein subunit vaccines, viral-vector vaccines and nucleic acid (mRNA and DNA) vaccines. Despite numerous Randomised Controlled Trials (RCTs), comprehensive systematic review and comparative meta-analysis have not been performed to validate the immunogenicity, safety and efficacy of COVID-19 vaccines in the healthy adult population. We aim to fulfil this unmet void. We searched for peer-reviewed articles about RCTs of the COVID-19 vaccines on healthy adults (18-64 years) available in eight major bibliographic databases (PubMed, EMBASE, Web of Science, Cochrane Library, Scopus, ScienceDirect, POPLINE, HINARI) till August 28, 2022. The Risk of Bias (RoB) was assessed using the Cochrane RoB-2. Random effects meta-analysis was conducted by pooling dichotomous outcomes using risk ratios (safety outcomes) and continuous outcomes using standardised mean differences (immunogenicity outcomes). Efficacy outcomes were summarised narratively. Moderate to high-quality evidence suggests that those receiving COVID-19 vaccines had significantly higher immune responses compared to placebo. Serious adverse events were rare, confirming that COVID-19 vaccines were safe and immunogenic for the healthy adult population. Remarkably, adverse events were the least common in inactivated vaccines, and nucleic acid vaccines were the most immunogenic. The efficacies of COVID-19 vaccines ranged from 21.9% to 95.9% in preventing COVID-19. We endorse all four types of COVID-19 vaccines for public health policy implementing taskforces. Yet, meta-analyses based on individual patient data are warranted for more extensive measurement of differential impacts of COVID-19 vaccines on different genders, ethnicities, comorbidities and types of vaccine jabbed.

The availability of safe and effective vaccine alone does not save lives; it is the inoculation plus other public health measures that do. Recent reports suggest the growing trend in vaccine preferential bias in parts of the world but not much in Europe. The present paper aims to investigate the occurrence of COVID-19 vaccine preferential bias in Europe for effective vaccination planning and pandemic control. MethodData on vaccine delivered and vaccination campaigns of the EU member states was collected from Eu center for disease control (EUCDC) on COVID-19 vaccination radar. The data was processed for analysis on MS excel and both descriptive and statistical analysis was done with IBMs SPSS version 21. Analysis was performed at 95% confidence interval and statistically significant difference was considered at p < 0.05. ResultsWe observed statistically significantly lower vaccine uptake compared to the vaccine delivered doses in the present study (average at 62.678 +/-3.928%) (p< 0.05, CI = 95%). Great variances in uptake for Oxford-AstraZeneca vaccines (50.927 +/-4.626 %) compared to Pfizer-Biontech vaccine (86.285 +/- 2.1052 %) was observed compared to previous prospective study on the wiliness to receive COVID-19 vaccine in the region (75%). ConclusionPublic health practitioners and policy makers need to factor the existence of COVID-19 preferential bias based on vaccine type or manufacturer. This will enable them introduce policies including public educational campaigns to overcome biasness on the wiliness to inoculate thereby enhancing vaccine uptake for smooth and effective control of the pandemic.

This study investigates vaccine hesitancy among the 50+ population in Europe and Israel during the COVID-19 pandemic, focusing on the role of national contexts alongside individual determinants. Utilizing data from the SHARE Corona Surveys (SCS1 and SCS2), the analysis includes over 48,000 respondents across 28 countries. The framework is guided by the WHOs Complacency, Convenience, and Confidence (3Cs) model to explore factors influencing vaccination intent. Complacency examines perceived risks and visibility of the viruss consequences, convenience evaluates accessibility and affordability of vaccines, and confidence assesses trust in vaccines, healthcare systems, and policymakers. Key findings suggest that higher COVID-19 mortality rates and stricter containment measures reduce complacency and increase vaccine uptake. Greater healthcare expenditure and Human Development Index (HDI) scores enhance convenience, leading to higher vaccination rates. Additionally, trust in governments and health authorities as well as in the vaccine itself predict confidence, shaping vaccination intent. The study reveals significant national disparities in vaccination attitudes and behaviours, linked to socio-economic factors and healthcare quality. By incorporating multivariate logistic regression models, the research highlights the interplay between individual and national factors, suggesting that successful vaccination campaigns require a holistic approach addressing both personal hesitations and systemic barriers. This research hence underscores the importance of public trust, robust healthcare systems, and targeted communication strategies to mitigate vaccine hesitancy and improve pandemic response outcomes.

BackgroundThe presented meta-analysis was developed in response to the publication of several studies addressing COVID-19 vaccines hesitancy. We aimed to identify the proportion of vaccine acceptance and rejection, and factors affecting vaccine hesitancy worldwide especially with the fast emergency approval of vaccines. MethodsOnline database search was performed, and relevant studies were included with no language restriction. A meta-analysis was conducted using R software to obtain the random effect model of the pooled prevalence of vaccine acceptance and rejection. Eggers regression test was performed to assess publication bias. Quality assessment was assessed using Newcastle-Ottawa Scale quality assessment tool. ResultsThirty-nine out of 12246 articles met the predefined inclusion criteria. All studies were cross-sectional designs. The pooled proportion of COVID-19 vaccine hesitancy was 17% (95% CI: 14-20) while the pooled proportion of COVID-19 vaccine acceptance was 75% (95% CI: 71-79). The vaccine hesitancy and the vaccine acceptance showed high heterogeneity (I2=100%). Case fatality ratio and the number of reported cases had significant effect on the vaccine acceptance as the pooled proportion of vaccine acceptance increased by 39.95% (95% CI: 20.1-59.8) for each 1% increase in case fatality (P<0.0001) and decreased by 0.1% (95% CI: -0.2-0.01) for each 1000 reported case of COVID-19, P= 0.0183). ConclusionTransparency in reporting the number of newly diagnosed COVID-19 cases and deaths is mandatory as these factors are the main determinants of COVID-19 vaccine acceptance.

BackgroundRace and ethnic disparities in cancer incidence rates and the prevalence of cytomegalovirus (CMV) are known to exist in the United States (U.S.) but also across broad geographic expanses. CMV prevalence seems to inversely contrast tumor incidence rates both in ethnic groups and globally. Is there a biological link between cancer and CMV infection? Most recent clinical results seem to certify it. MethodsGlobal cancer data were retrieved from the World Health Organization (WHO) database. Incidence of cancer and CMV seroprevalence (73 countries) were subjected to Spearmans correlation test. The Bayesian framework was adopted for CMV seropositivity variables. Relevant data for the U.S. were extracted from publications based on the Surveillance, Epidemiology, and End Results (SEER) registries and the National Health and Nutrition Examination Surveys (NHANES), 1988-2004. ResultsAn inversely directed coupling between cancer and CMV seropositivity across diverse ecologies and cultural domains suggest a global oncoprotective effect of the CMV (Spearmans{rho} = -0.732; p<0.001). Rates of all cancers combined and CMV seropositivity show an opposite association (p<0.001) among the races and foremost U.S. ethnic groups. ConclusionThe racial/ethnic incidence of cancers and CMV seropositivity are inversely proportional both in the U.S. and globally. This would support a view that CMV is a potential driver against tumorigenesis. An absence of CMV infection abrogates protection against malignant clones afforded to an infected host. Abating CMV seroprevalence may relate causally to the buildup of malignancies in U.S. and the West world countries with thriving hygiene and healthcare systems. ImportanceIncreasing evidence substantiates the potential of cytomegalovirus (CMV) to counteract tumors, particularly in the field of anti-cancer vaccinology, leading to extended periods of survival. This research unveils a robust and inverse correlation between the prevalence of CMV and the occurrence of cancer both within the United States and on a global scale (73 countries), hinting at the ability of CMV to inhibit tumor development. Furthermore, this phenomenon remains consistent across various racial and ethnic groups within the United States and applies to a diverse range of cancer types. A notable pattern emerges: the higher the prevalence of the viral infection, the lower the incidence of tumors within a given country. These findings support existing insights from clinical and experimental investigations, underscoring the notion that this effect becomes apparent at the level of entire nations and populations worldwide.

BACKGROUNDAmong the various driving factors for vaccine hesitancy, confidence in the safety associated with the vaccine constitutes as one of the key factors. This study aimed at comparing the adverse effects of COVID-19 vaccines with the Flu vaccines. METHODSThe VAERS data from 01/01/2020 to 08/20/2021 were used. The MedDRA terms coded by VAERS were further aggregated by a clinician into clinically meaningful broader terms. RESULTSVarious common adverse events between Flu and COVID-19 vaccines have been identified. Adverse events such as headache and fever were very common across all age groups. Among the common adverse events between Flu and COVID-19 vaccine, the relative risk along with 95% CI indicated that such common adverse events were more likely to be experienced by COVID-19 vaccine users than Flu vaccine users. Our study also quantified the proportion of rare adverse events such as Guillain Barre Syndrome and Gynecological changes in the VAERS database for COVID-19 vaccines. CONCLUSIONSBased on the available data and results, it appears that there were some common adverse events between Flu vaccines and COVID-19 vaccines. These identified common adverse events warrant further investigations based on the relative risk and 95% CI.

The COVID-19 pandemic is the largest epidemic of the 21st century so far. Over 650 million people have already been infected with the SARS-CoV-2 virus. One of the ways to stop this pandemic, is to vaccinate the population and gain herd immunity. Many different vaccines are being used around the world, with differing efficacy. This review summarizes the 79 publications on the efficacy of the currently existing COVID-19 vaccines. It shows that there are eleven vaccines that have efficacy data published in a PubMed-indexed scientific journal. Most research has been done on the Pfizer/BioNTech BNT162B2 vaccine, and the eleven vaccines generally have a high efficacy in preventing illness. The Pfizer (86%-100%), Moderna (93.2%-94.1%), Sputnik-V (91.6%) and Novavax ([~]90%) vaccines show the highest efficacy, followed by the Sinovac (83.5%), QazCovid-in 82%) and Covaxin (77.8%) vaccines. The Oxford/AstraZeneca (69% - 81.5%) and Johnson & Johnson (66%) vaccines have lower efficacy in preventing illness. This overview also shows efficacies other than in preventing illness (e.g. asymptomatic, severe illness, hospitalization, death) in some cases. The results also show that the vaccines have specific effects on specific age groups (e.g. adolescents, adults, elderly) and people with diseases (e.g. leukemia, other cancers, HIV). Future research in this area will mostly focus on vaccine efficacy on specific strains of the SARS-CoV-2 virus (such as the Omicron variant) as well as the efficacy of booster vaccinations.

Over the past decades, vaccination has proven to be largely beneficial to global health. Despite vaccine efficacy, the French population has been recently affected by more anti-vaccination attitudes and vaccine refusal, and it is therefore necessary to develop and validate tools to study this health issue. The Vaccination Attitudes Examination scale is a brief 12-item questionnaire targeting adults, that assesses general attitudes towards vaccination. The aims of the study were (1) to translate and adapt the original English version of the scale into French and (2) to test the psychometric properties of the scale in a French population-based sample of adults. We included 450 French speaking adults that completed the French Vaccination Attitudes Examination scale and other questionnaires in order to assess convergent and divergent validities. Exploratory and confirmatory factor analyses showed that the French version of the Vaccination Attitudes Examination scale replicated the factorial structure of the original scale. Moreover, it demonstrated high internal consistency, good convergent and divergent validities, and excellent temporal stability. Also, scores on the scale differentiated vaccinators from non-vaccinator respondents. Results on the scale provides us with insight into factors involved in vaccine hesitancy in France, therefore allowing French authorities and policy makers to address these specific concerns and by consequence improve vaccine acceptance rates in this country.

Present evidence of the safety of BNT162b2 Vaccine in adolescents of 12 to 15 years relies only on 2260 subjects involved in phase 3 study. Therefore, clinical and post-clinical safety assessment of BNT162b2 Vaccine in Age Group of 12 to 15 Years is urgently needed to make an accurate judgment for mass vaccination. A rapid systemic review was conducted to determine safety profile of BNT162b2 Vaccine in Age Group of 12 to 15 Years following the PRISMA guidelines. Published literature before August 15, 2021 were searched in PubMed, Scopus, Web of Science, Embase, the Cochrane library and MedRxiv, using the defined search words. 135 records found from 6 databases, of which 4 studies (2 studies from NEJM and 2 MMWR), total subject who received at least one dose of vaccine: 64969, were included in this systemic review per the inclusion criteria. The major events reported in clinical phase and post-authorisation observational studies are pain at injection site (local), fatigue (systemic), headache (systemic), chill (systemic), diarrhoea (systemic) and joint pain (systemic). Post-authorisation observational study (n = 62,709) reported about 50% lower major systemic events, specifically, fatigue, headache, chill, diarrhoea and join pain and about 25% lower major local event, specifically, pain at injection site, than phase 3 clinical study (n = 1,131). Our study suggest that higher adherence rate (>97 percent received second dose) in clinical phase 3 and significantly lower incident of major local and systemic events in post-authorisation observational study indicating that BNT162b2 vaccine has highly favourable safety profile.

On April 13, 2021 the Centers for Disease Control and Prevention (CDC) and Food and Drug Administration (FDA) recommended in a pause in use of the Johnson & Johnson (J&J)-Janssen COVID-19 vaccine due to reports of cerebral venous sinus thrombosis (CVST) in recently vaccinated individuals. The announcement of the pause required development of a coordinated communication strategy under extreme time pressure and careful messaging by stakeholders to mitigate reduced public confidence in COVID-19 vaccines, as was observed following the temporary suspension of the Oxford-AstraZeneca vaccine in many countries. In this survey study, we evaluated understanding and impressions of the CDCs public online information about the J&J-Janssen pause among unvaccinated US adults.