Benefits Of Vaccination Research Articles

Encouraging vaccination against COVID-19 has no compensatory spillover effects

Abstract Effective communication is essential for delivering public health messages and enabling behaviour change. Little is known about possible backfiring, or spillover effects, of COVID-19 vaccine messaging. In a study with n = 1,848 United Kingdom (UK) adults, we assess whether communication strategies that target vaccine hesitancy have any unintended, positive or negative, spillover effects on people's intention to engage in protective, compliance and prosocial behaviours. In June–July 2021, we conducted an online experiment to assess the potential spillover effects of three messages, emphasising (a) the medical benefits of COVID-19 vaccination, (b) the non-medical collective benefits of vaccination or (c) the non-medical individual benefits of holding a vaccination certificate. Exposure to different messages did not significantly affect people's intention to engage in protective, compliance, or prosocial behaviours. Instead, vaccination status (being vaccinated vs not) was positively associated with intentions to engage in protective, compliance and prosocial behaviours. Our results suggest that communication strategies that aim to increase vaccination uptake do not have any unintended effects on other health behaviours and vaccination campaigns can be tailored to specific populations to increase uptake and compliance.

Barriers to COVID-19 Vaccination in a Troop of Fleet Antiterrorism Security Team Marines: Observational Study.

In 2019, the World Health Organization declared the reluctance to vaccinate despite the availability of vaccination services as one of the top 10 threats to global health. In early 2021, self-reported reluctance to vaccinate among military personnel might have been considered a significant threat to national security. Having a choice architecture that made COVID-19 vaccination optional rather than required for military personnel could have inadvertently undermined military readiness if vaccination uptake did not reach an acceptable threshold. The purpose of this observational study was to examine Marines' self-reported reasons for planning to decline the COVID-19 vaccine to understand their barriers to vaccination. As the vaccination became available to 1 company of Fleet Antiterrorism Security Team (FAST) Marines in early 2021, company command required those planning to decline vaccination to write an essay with up to 5 reasons for their choice. These essays provided the data for this study. Qualitative descriptive analysis with elements from grounded theory was used to thematically categorize FAST Marines' written reasons for planning to decline the COVID-19 vaccine into a codebook describing 8 key behavioral determinants. Interrater agreement among 2 qualitatively trained researchers was very good (κ=0.81). A troop of 47 Marines provided 235 reasons why they planned to decline the COVID-19 vaccine. The most frequent reasons were difficulty understanding health information (105/235, 45%), low estimates of risk (33/235, 14%), and fear of physical discomfort (29/235, 12%). Resulting interventions directly targeted Marines' self-reported reasons by reducing barriers (eg, normalized getting the vaccine), increasing vaccine benefits (eg, improved access to base gyms and recreational facilities), and increasing nonvaccine friction (eg, required in writing 5 reasons for declining the vaccine). Understanding the barriers military personnel experience toward COVID-19 vaccination remains critical as vaccine acquisition and availability continue to protect military personnel. Insights from subpopulations like FAST Marines can enhance our ability to identify barriers and appropriate intervention techniques to influence COVID-19 vaccination behaviors.

Benefit–risk assessment for the Novavax COVID-19 vaccine (NVX-CoV2373)

A benefit–risk assessment of NVX-CoV2373, a vaccine to prevent COVID-19, was conducted to determine if the benefits of vaccination outweigh the risks of myocarditis/pericarditis.This analysis used data on myocarditis/pericarditis cases observed in the NVX-CoV2373 clinical studies, real-world data of mRNA COVID vaccine effectiveness against predominant SARS-CoV-2 strains in early 2023, and recent COVID-19 burden of disease data from the United States. The benefits of NVX-CoV2373 vaccination were estimated as the number of COVID-19 cases, hospitalizations, and deaths prevented. The risks of myocarditis/pericarditis cases and related hospitalizations and deaths occurring within 7 days of vaccination were also estimated.In our analysis, vaccination with NVX-CoV2373, per 100,000 vaccinated, resulted in an estimated 1805 COVID-19 cases prevented compared with an estimated 5.3 excess myocarditis/pericarditis cases. The number of COVID-19 hospitalizations and deaths prevented were also greater than vaccine-associated myocarditis/pericarditis hospitalizations and deaths.Our analysis indicates a positive benefit–risk balance for NVX-CoV2373.

The impact of health beliefs and trust in health information sources on SARS-CoV-2 vaccine uptake.

Health beliefs may mediate the relationship between trust and vaccination decisions, as confidence in online health information has expanded quickly. However, little is known about how health attitudes and trust in health information affect COVID-19 vaccine intention. This study aimed to assess the effect of health beliefs and trust in information sources on the willingness to receive a COVID-19 vaccine among the general public in Saudi Arabia. This study was designed and carried out at the Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia. Selected items were extracted from the Saudi Residents' Intention to Get Vaccinated Against COVID-19 (SRIGVAC) survey. They were categorized and validated into constructs of a health belief model (the perceived threat of COVID-19, vaccine-related benefits, barriers, and safety concerns) and trust in health information (from online platforms and health authorities/providers). Regression analysis and parallel mediation were used to assess the predictors of vaccination intentions. Based on the responses of 3,091 participants, vaccine-related barriers and safety concerns negatively influenced vaccination intention, whereas vaccine benefits and the perceived threat of COVID-19 were positively correlated with vaccination intention. Trust in online health information had a direct relationship with intentions (β = 0.09, p < 0.0001) as well as indirect relationships through the perceived benefits (β = 0.095), the perceived barriers (β = -0.029), and the perceived safety concerns toward the vaccine (β = -0.010). The relationship between the willingness to vaccinate and trust in authentic information was fully mediated by all domains of health beliefs, with indirect coefficients of 0.004, 0.310, -0.134, and -0.031 for the perceived threat, vaccine benefits, barriers, and safety concerns, respectively. The relationship between the willingness to vaccinate and trust in authentic information was fully mediated by all domains of health beliefs. Vaccine coverage in Saudi Arabia can be optimized by targeting the health beliefs of the general public.

Knowledge, Attitude, and Practice of Hepatitis B Vaccination among Dentists in Lebanon.

The hepatitis B virus (HBV) is a serious occupational hazard for healthcare workers, including dentists. The purpose of this study is to assess dentists' knowledge, attitude, and practice (KAP) with respect to hepatitis B vaccination. A cross-sectional survey of a representative sample of dentists (n = 349) from Lebanon was carried out. Participants' knowledge of hepatitis B, attitudes toward vaccination, and immunization habits were assessed using a standardized questionnaire. To examine the data, descriptive statistics were used, and associations between variables were investigated using appropriate statistical tests. The study found that most participating dentists are HBV-vaccinated. These dentists boast a basic to a significantly substantial understanding of HBV infection prevention strategies, such as immunization, routine preventive measures, and handling equipment. Notwithstanding the generally positive attitudes towards vaccination, a proportion of dentists lacked some HBV prevention practices, specifically with respect to conducting regular follow-ups of anti-HBs titer levels and getting booster vaccination doses when warranted. This study sheds light on the KAP of hepatitis B immunization among Lebanese dentists. The findings emphasize the significance of focused educational efforts in view of improving awareness and encouraging a more thorough understanding of the benefits of vaccination. The study provides useful data that can be used to influence public health policies as well as activities aimed at increasing hepatitis B vaccination rates among dental professionals in Lebanon. How to cite this article: Yared G, Sokhn ES, Al-Khatib A, et al. Knowledge, Attitude, and Practice of Hepatitis B Vaccination among Dentists in Lebanon. J Contemp Dent Pract 2024;25(2):134-140.

Podcast: Need for Quality Evidence for Decision-Making on Seasonal Influenza Vaccines.

Seasonal influenza is usually considered an acute respiratory infection with a full recovery within a week. In addition to the traditional outcomes, there is now evidence of indirect effects in terms of neurological and functional complications. Major organ systems can be affected, underlining the need for preventative measures against infection. The aim of this podcast, featuring Dr. Ann Falsey, Dr. Stefania Maggi, and Dr. Tor Biering-Sørensen, is to outline influenza complications beyond acute respiratory disease, as well as discussing the need for quality of evidence when evaluating influenza vaccines. Assessing the benefits of vaccination can be challenging. To ensure a high quality of evidence, the innovative randomization of patients within the study design to avoid bias and the assessment of additional outcomes beyond immunogenicity as well as the inclusion of a broad population-including frail or vulnerable individuals-are essential. Studies leveraging nationwide registries such as the DANFLU-2 trial in Denmark highlight the advantages of a digitalized healthcare system for conducting large-scale randomized trials. Furthermore, large-scale trials such as the Gravenstein study have supplied a sizable body of evidence supporting the use of high-dose influenza vaccine in older adults. In conclusion, achieving a high quality of evidence is key for decision-making on seasonal influenza vaccines.

COVID-19 vaccines breakthrough infection and adverse reactions in medical students: a nationwide survey in Iran.

There are different types of COVID-19 vaccines approved worldwide. Since no national studies focus on vaccine-related adverse reactions and breakthrough cases, this study aimed to investigate the rate of adverse events and COVID-19 infection in medical students in Iran. This retrospective cohort study included Iranian medical students who received two doses of COVID-19 vaccines. The medical team gathered the demographic characteristics, comorbidities, type of vaccine, adverse events following vaccination, and history of COVID-19 infection data through a phone interview. The frequency of adverse events and breakthrough infection was stratified by vaccine type (ChAdOx1-S, Gam-COVID-Vac, and BIBP-CorV). A total of 3,591 medical students enrolled in this study, of which 57.02% were females, with a mean age of 23.31 + 4.87. A PCR-confirmed and suspicious-for-COVID-19 breakthrough infection rate of 4.51 and 7.02% was detected, respectively. There was no significant relation between breakthrough infection and gender, BMI, blood groups, and comorbidities. However, there was a significant difference in breakthrough infection rate among different types of vaccines (p = 0.001) and history of COVID-19 infection (p = 0.001). A total of 16 participants were hospitalized due to COVID-19 infection after vaccination for reasons such as dyspnea, abnormal imaging, or decreased oxygen saturation. No severe infection or death was observed in the studied population. Vaccination prevented severe COVID-19 infection, although a high breakthrough infection rate was evident among Iranian medical students during the Delta variant's peak. Vaccine effectiveness may be fragile during emerging new variants and in high-exposure settings. Moreover, adverse events are rare, and the benefits of vaccination outweigh the side effects. However, many limitations challenged this study, and the results should be cautious.

Waning effectiveness of mRNA COVID-19 vaccines against inpatient and emergency department encounters.

In the United States, most real-world estimates of COVID-19 vaccine effectiveness are based on data drawn from large health systems or sentinel populations. More data is needed to understand how the benefits of vaccination may vary across US populations with disparate risk profiles and policy contexts. We aimed to provide estimates of mRNA COVID-19 vaccine effectiveness against moderate and severe outcomes of COVID-19 based on state population-level data sources. Using statewide integrated administrative and clinical data and a test-negative case-control study design, we assessed mRNA COVID-19 vaccine effectiveness against SARS-CoV-2-related hospitalizations and emergency department visits among adults in South Carolina. We presented estimates of vaccine effectiveness at discrete time intervals for adults who received one, two or three doses of mRNA COVID-19 vaccine compared to adults who were unvaccinated. We also evaluated changes in vaccine effectiveness over time (waning) for the overall sample and in subgroups defined by age. We showed that while two doses of mRNA COVID-19 vaccine were initially highly effective, vaccine effectiveness waned as time elapsed since the second dose. Compared to protection against hospitalizations, protection against emergency department visits was found to wane more sharply. In all cases, a third dose of mRNA COVID-19 vaccine conferred significant gains in protection relative to waning protection after two doses. Further, over more than 120 days of follow-up, the data revealed relatively limited waning of vaccine effectiveness after a third dose of mRNA COVID-19 vaccine.

Addressing COVID-19 Vaccine Hesitancy and Uptake Among African Immigrants: Lessons from a Community-Based Outreach Program.

In 2021, the African Cultural Alliance of North America (ACANA) implemented a community-based vaccine education and outreach program to decrease hesitancy and increase COVID-19 vaccine uptake among African immigrants in Philadelphia. The program had three components: (1) tailored messaging on the benefits of vaccines by trusted community health navigators in familiar languages/dialects, (2) use of educational/tabling events, and (3) establishment of a vaccine clinic in community settings. Using secondary data analysis, in-depth interviews, focus group discussions and a self-administered survey, we explored (i) the impact and effectiveness of the outreach program and extent of vaccine uptake, (ii) African immigrants' beliefs about the COVID-19 pandemic and the vaccine, and (iii) barriers and facilitators of vaccine knowledge, uptake, and hesitancy.Our analysis showed that ACANA's outreach program was effective in addressing several cultural, logistic, and systematic barriers to vaccine uptake. The program distributed 2000 educational/informational flyers,reached 3000 community members via social media campaigns,and an additional2320 through other person-to-person outreach events.The programwas effective and resulted inthe vaccination of 1265 community members over the course of the outreach. The impact of this outreach underscores the critical role of community-based organizations in addressing COVID-19 vaccine hesitancy and increasing vaccine uptake in underserved and minority communities. The paper concludes with suggestions and recommendations for using community-based outreach programs to increase COVID-19 vaccine uptake and decrease hesitancy.

Association of COVID-19 vaccination with duration of hospitalization in older adults in Hong Kong

IntroductionThe association between COVID-19 vaccination and length of hospital stay may provide further insight into vaccination benefits, but few studies have investigated such associations in detail. We aimed to investigate the association between COVID-19 vaccination and length of hospital stay in COVID-19 patients during Omicron waves in Hong Kong, and explore potential predictors. MethodsThis retrospective cohort study was conducted on local patients aged ≥60 years who were admitted due to COVID-19 infection in Hong Kong in 2022, from 1 February to 22 November, and with 28 days of follow-up since admission. The exposure was either not vaccinated; or having received 2/3/4 doses of CoronaVac (Sinovac); or 2/3/4 doses of BNT162b2 (BioNTech/Fosun Pharma/Pfizer). Length of stay in hospital was the main outcome. Accelerated failure time models were used to quantify variation in hospital stay for vaccinated compared with unvaccinated patients, accounting for age, sex, comorbidity, type of vaccine and number of doses received, care home residence and admission timing; stratified by age groups and epidemic waves. ResultsThis study included 32,398 patients aged 60 years and above for main analysis, their median (IQR) age was 79 (71–87) years, 53% were men, and 40% were unvaccinated. The patients were stratified by confirmation prior to or since 23 May 2022, resulting in a sample size of 15,803 and 16,595 in those two waves respectively. Vaccinated patients were found to have 13–39% shorter hospital stay compared to unvaccinated patients. More vaccine doses received were associated with shorter hospital stay, and BNT162b2 recipients had slightly shorter hospital stays than CoronaVac recipients. ConclusionVaccination was associated with reduced hospital stay in breakthrough infections. Increased vaccination uptake in older adults may improve hospital bed turnover and public health outcomes especially during large community epidemics.

Effect of information provision on parental intention toward COVID-19 vaccination for children: a nationwide survey experiment

The reluctance of parents to vaccinate their children against COVID-19 was prevalent particularly when uncertainty over vaccination outcomes prevailed. We conducted a nationwide randomized online survey experiment to assess the effect of information provision on parental intention for COVID-19 vaccination before the government started vaccination for children in South Korea. Parents of elementary school children were provided with either no information (Control), information on vaccine profile (vaccine informed group; VI), or COVID-19 (disease informed group; DI). Among 359,110 participants, parental intention for vaccination of children was significantly higher in both VI and DI groups compared with the Control group. In terms of effect size, information on COVID-19 vaccine increased likelihood to vaccinate by 1620 per 100,000 parents and reduced vaccine hesitancy by 1340 per 100,000 parents. Consistently with the positive effect on vaccination intention, both VI and DI interventions increased participants’ perceptions on vaccination benefits being higher than its risks and vaccination risks being lower than health risks of COVID-19 infection, and self-reported trust in COVID-19 information. Our results lend strong support to the claim that the provision of targeted, tailored information on COVID-19 vaccine and infection increases parental intention to vaccinate children and reduces vaccine hesitancy.

Protective role of Bacillus Calmette–Guérin vaccine in Alzheimer's disease progression: A systematic review and meta-analysis

Introduction: Alzheimer's disease (AD) represents a significant societal challenge, highlighting the need to explore effective prevention and treatment approaches. Recent literature has suggested that Bacillus Calmette-Guérin (BCG) vaccine may be a viable therapeutic option for immune disorders associated with AD due to its immunomodulatory properties and protection against various diseases. MethodsThis systematic review aimed to evaluate the association of BCG vaccine in the prevention of AD using six medical-scientific databases. A meta-analytical approach was undertaken to estimate the risk of AD incidence in patients with and without BCG vaccine exposure, followed by subgroup analyses. A risk of bias (RoB) assessment was performed using the Newcastle-Ottawa Scale (NOS). ResultsSix cohort studies meeting our inclusion criteria were included (47,947 participants) in the study. From our meta-analysis, intravesical BCG vaccine administration lowered the risk of incidence of AD by 26% in non-muscle-invasive bladder cancer (p < 0.00001). Subgroup analyses showed that BCG vaccination showed a potentially notable preventive effect on AD in older adults (>75 years) and female participants. Conversely, significant heterogeneity in results was observed among male participants and those aged <75 years. The RoB was low in three studies and unclear in the remaining studies. ConclusionsAlthough our results support the potential benefits of BCG vaccine in preventing AD in specific demographics, we remain cautious about interpreting such results. Further research examining the implications of BCG vaccination for prevention and possible treatment of AD should be undertaken in the future.

Acceptance of Flu Vaccine among Parents of Diabetic Children in Jordan.

There is a critical need to understand vaccine decision-making in high-risk groups. This study explored flu vaccine acceptance among Jordanian parents of diabetic children. Employing a cross-sectional approach, 405 parents from multiple healthcare centers across Jordan were recruited through stratified sampling, ensuring a broad representation of socioeconomic backgrounds. A structured questionnaire, distributed both in-person and online, evaluated their knowledge, attitudes, and acceptance of the flu vaccine for their diabetic children. The results indicated that only 6.4% of the study sample reported vaccinating their children against the flu annually, and only 23% are planning to vaccinate their children this year. A multinomial logistic regression analysis revealed notable variability in responses. Specifically, parents with a positive attitude towards the flu vaccine and those with older children had less odds to reject the vaccine (OR = 0.589, 95% CI (0.518-0.670), p < 0.001 and OR = 0.846, 95% CI (0.736-0.974), p = 0.02, respectively). Conversely, prevalent misconceptions regarding vaccine safety and efficacy emerged as significant barriers to acceptance. Our findings advocate for targeted educational programs that directly address and debunk these specific misconceptions. Additionally, strengthened healthcare communication to provide clear, consistent information about the flu vaccine's safety and benefits is vital to help enhance vaccine uptake among this vulnerable population, emphasizing the need to address specific concerns and misinformation directly.

Pharmacists’ role in maternal immunization

Maternal immunization is an important strategy to safeguard infants against vaccine-preventable diseases such as pertussis, which poses a significant economic burden on the health care system. Although the Tetanus, Diphtheria, and Pertussis vaccine has been recommended for pregnant individuals since 2018, uptake varies widely across Canadian provinces. As 4.5 million Canadians do not have access to a regular physician, there is a need to find alternate ways of informing pregnant individuals about maternal immunization schedules. Given the wide accessibility of pharmacists across Canada, they should have a leading role in informing pregnant individuals about maternal vaccines. Training guidelines for pharmacists would ensure informative and effective conversations about vaccinations and promote vaccine safety and benefits, facilitating administration. Increased participation from pharmacists can significantly contribute to improving maternal and child health outcomes, with the goal of reducing the burden of vaccine-preventable diseases in Canada.

Reversible cerebral vasoconstriction syndrome and posterior reversible encephalopathy syndrome following vaccination: analysis of the VAERS database and systematic review.

This study aimed to analyze the Vaccine Adverse Event Reporting System (VAERS) database and systematically review the literature to provide a comprehensive analysis of reversible cerebral vasoconstriction syndrome (RCVS) and posterior reversible encephalopathy syndrome (PRES) secondary to vaccination. The authors analyzed the VAERS database and conducted a systematic review following PRISMA guidelines. The inclusion criteria for VAERS data were a score of ≥3 on the RCVS2 score and/or radiographic findings consistent with the diagnosis of RCVS or PRES. The systematic review was registered with PROSPERO. Our combined data set included 29 cases (9 RCVS and 20 PRES). Most cases were women (72.4%) with a mean age of 50.7 years (SD 19.4 years). Most cases were associated with COVID-19 mRNA vaccines (58.6% Moderna, 20.7% Pfizer). Hypertension (37.9%), hyperlipidemia (13.7%), chronic kidney disease (CKD) (10.3%), and end-stage renal disease (6.8%) were common comorbidities. Furthermore, 20.6% (6/29) of cases were on immunosuppression therapy for various reasons. The mean time to symptom onset was 10.49 days after vaccination (SD 18.60), and the mean duration of hospitalization was 7.42 days (SD 5.94). The symptoms reported the most frequently were headache (41.3%), elevated blood pressure (31.0%), and emesis (17.2%). Typical radiographic findings included T2/FLAIR hyperintensities affecting the parieto-occipital lobes, indicative of vasogenic and/or cytotoxic edema. This study provides a comprehensive analysis of postvaccine RCVS and PRES. Both disease states were seen most often in those with pre-existing risk factors such as female sex, age over 50, hypertension, renal disease, and immunosuppression. Vaccines and their associated immune response may cause endothelial dysfunction leading to cerebral vasospasm and loss of cerebral autoregulation. However, further research is required to understand the underlying pathophysiological mechanisms. Despite the associations found, the absolute risk of these syndromes remains extremely low compared to the immense benefits of vaccination.

Knowledge, attitude, and practices of mothers with children under 1-year-old regarding post-vaccination care and related factors in Quang Ngai City, Quang Ngai province, 2023

Objectives: Describe the knowledge, attitudes, and practices of mothers with children under one year of age on post-vaccination care and some related factors in Quang Ngai City, Quang Ngai province, in 2023. Methods: A cross-sectional study, interviewing 345 mothers with children under 1-year-old in 08 communes and wards of Quang Ngai City, Quang Ngai province, from February to April 2023. Results: Good knowledge achieved by mothers of children under one year of age on childcare after vaccination was 62.0%. Good attitude and good practice of mothers on childcare after vaccination reached the rate of 89.0% and 74.0%, respectively. The study found an association between the mothers' good knowledge, attitudes and educational level of mothers (OR=2.49 (1.58-3.91)), the mothers whose children experienced adverse events after immunization (AEFI) (OR=2.57 (1.52-4.33)) or had siblings who had experienced AEFI have significantly better knowledge of post-vaccination care (OR=3.74 (1.41-9.95)), the number of communication channels also have positive influence to mother’s knowledge (OR=2.60 (1.23-5.52)). Conclusions: Diversify forms of communication and further promote the role of health workers in providing knowledge about the benefits of vaccination and how to detect and treat AEFI, focusing on mothers with low levels of education. Keywords: Knowledge, attitude, practice, adverse events after immunization.

Side Effects of COVID Vaccination among the Residents of Shimla

Objective; To study the side effects of COVID-19 vaccines among the patients visiting health centre at Shimla. Methods: Patients visiting the health centre were enquired about the side effects of COVID-19 vaccine experienced by them. Results: 38% felt no side effects, neither after 1st dose, nor after 2nd dose. 2% reported improvement in overall health. 18% reported side effects after 2nd dose. 43% experienced side effects after 1st dose. 38% felt no side effects.33% had fever. 8% had body pain, 6% had pain in the arm, 5% had weakness and fatigue.2% had joint pains. 1% each had pain in legs, hypertension, giddiness, stiffness in body and diarrhoea. 1% had clotting. 1% each experienced increase in appetite and improvement in body pains after the vaccination. Conclusions; Majority of the patients had either no side effects or only mild side effects and some had reported in improvement in overall heath. Practical implications: This study demonstrated that benefits of vaccination greatly outweigh the risks.

Effectiveness of Sinopharm's BBIBP-CorV Booster Vaccination against COVID-19-Related Severe and Critical Cases and Deaths in Morocco during the Omicron Wave.

This study investigates the effectiveness of the 1st booster dose against COVID-19 severe and critical hospitalizations and deaths occurring due to the Omicron wave in Morocco. This study uses nationally representative data on COVID-19 from 15 December 2021 to 31 January 2022. The aim is to investigate the effectiveness of the inactivated COVID-19 vaccine BBIBP-CorV (Sinopharm) 1st booster dose against the Omicron wave in Morocco using real-world data established from nationally representative statistics on COVID-19 cases, deaths and vaccinations. The screening method was used to estimate vaccine effectiveness against COVID-19 severe or critical hospitalization and COVID-19-related deaths. The data were grouped by, age subgroup, sex, week, and geographical area and were analyzed using binary logistic regression with an offset for vaccine coverage. The overall BBIBP-CorV VE estimate is 89% (95% CI 85 to 92) effective in curbing COVID-19 deaths, and 81% (95% CI 78 to 84 in curbing COVID-19 severe/critical hospitalizations. Death-related VE estimate was 86% (95% CI 81 to 90) for patients aged ≥65 years, 96% (95% CI 90 to 98) for those aged <65 years, 95% (95% CI 88 to 98) in no-risk factor patients, 91% (95% CI 85 to 94) with 1 risk factor, 90% (95% CI 83 to 95) with 2 risk factors, and 72% (95% CI 52 to 84) in patients with 3 risk factors and more. Severe/critical hospitalization VE estimate was 78% (95% CI 74 to 82) for patients aged ≥65 years, 87% (95% CI 82 to 90) for those aged <65 years, 86% (95% CI 80 to 90) in no-risk factor patients, 80% (95% CI 73 to 84) with 1 risk factor, 80% (95% CI 70 to 85) with 2 risk factors, and 80% (95% CI 68 to 86) in patients with 3 risk factors and more. BBIBP-CorV boosters are effective in increasing protection against the Omicron variant-related COVID-19 deaths and severe/critical hospitalizations. The protection is reduced with older age and higher risk factors. These findings emphasize the importance of targeted vaccination strategies for different demographic groups and underscore the protective benefits of the first booster BBIBP-CorV vaccine.

Balancing the benefits of vaccination: An envy-free strategy.

The Covid-19 pandemic revealed the difficulties of vaccinating a population under the circumstances marked by urgency and limited availability of doses while balancing benefits associated with distinct guidelines satisfying specific ethical criteria. We offer a vaccination strategy that may be useful in this regard. It relies on the mathematical concept of envy-freeness. We consider finding balance by allocating the resource among individuals that seem heterogeneous concerning the direct and indirect benefits of vaccination, depending on age. The proposed strategy adapts a constructive approach in the literature based on Sperner's Lemma to point out an approximate division of doses guaranteeing that both benefits are optimized each time a batch becomes available. Applications using data about population age distributions from diverse countries suggest that, among other features, this strategy maintains the desired balance, throughout the entire vaccination period. We discuss complementary aspects of the method in the context of epidemiological models of age-stratified Susceptible - Infected - Recovered (SIR) type.

NIHR Global Health Research Group on Vaccines for vulnerable people in Africa (VAnguard): Concept and Launch event report

Background Vaccination is an important public health intervention, but not everyone benefits equally. Biological, social and structural factors render some communities vulnerable and unable to secure optimal health benefits from vaccination programmes. This drives health inequity and undermines wider vaccine impact by allowing the persistence of non-immune communities as foci for recurrent disease outbreaks. The NIHR Global Health Research Group on Vaccines for vulnerable people in Africa (VAnguard) aims to understand how biological, social, and structural factors interact to impair vaccine impact in vulnerable African communities. Methods The VAnguard project will be implemented through three thematic work packages (1-3) and four cross-cutting work packages (4-7). Work package 1 will investigate the biological drivers and mechanisms of population differences in vaccine responses. Work package 2 will support the understanding of how structural, social and biological determinants of vaccine response interrelate to determine vaccine impact. Work package 3 will synthesise data and lead analyses to develop, model and test community-based integrated strategies to optimise vaccine access, uptake and effectiveness. Work package 4 will plan and implement field investigations (community survey and qualitative studies (with support of work package 2) to explore structural, social &amp; biological determinants impairing vaccine impact. Work package 5 will collaborate with work packages 1-4, to engage communities in designing interventions that aim to directly optimise vaccine impact through a process of co-learning and co-creation between them and the researchers. Work package 6 will build capacity for, and a culture of, consultative, collaborative multidisciplinary vaccine research in East Africa. Work package 7 will support the overall project management and governance. Following the project inception on the 1st of September 2022, project launch was held in November 2022. Conclusion Results from this project will contribute to the development of integrated strategies that will optimise vaccine benefits and drive health equity.