The effectiveness of COVID-19 vaccines in reducing the incidence, hospitalization, and mortality from COVID-19: A systematic review and meta-analysis

Mathematical assessment of the roles of age heterogeneity and vaccination on the dynamics and control of SARS-CoV-2

The COVID-19 pandemic, caused by SARS-CoV-2, disproportionately affected certain segments of society, particularly the elderly population (which suffered the brunt of the burden of the pandemic in terms of severity of the disease, hospitalization, and death). This study presents a generalized multigroup model, with m heterogeneous sub-populations, to assess the population-level impact of age heterogeneity and vaccination on the transmission dynamics and control of the SARS-CoV-2 pandemic in the United States. Rigorous analysis of the model for the homogeneous case (i.e., the model with m = 1) reveal that its disease-free equilibrium is globally-asymptotically stable for two special cases (with perfect vaccine efficacy or negligible disease-induced mortality) whenever the associated reproduction number is less than one. The model has a unique and globally-asymptotically stable endemic equilibrium, for special a case, when the associated reproduction threshold exceeds one. The homogeneous model was fitted using the observed cumulative mortality data for the United States during three distinct waves (Waves A (October 17, 2020 to April 5, 2021), B (July 9, 2021 to November 7, 2021) and C (January 1, 2022 to May 7, 2022)) chosen to align with time periods when the Alpha, Delta and Omicron were, respectively, the predominant variants in the United States. The calibrated model was used to derive a theoretical expression for achieving vaccine-derived herd immunity (needed to eliminate the disease in the United States). It was shown that, using the one-group homogeneous model, vaccine-derived herd immunity is not attainable during Wave C of the pandemic in the United States, regardless of the coverage level of the fully-vaccinated individuals. Global sensitivity analysis was carried out to determine the parameters of the model that have the most influence on the disease dynamics and burden. These analyses reveal that control and mitigation strategies that may be very effective during one wave may not be so very effective during the other wave or waves. However, strategies that target asymptomatic and pre-symptomatic infectious individuals are shown to be consistently effective across all waves. To study the impact of the disproportionate effect of COVID-19 on the elderly population, we considered the heterogeneous model for the case where the total population is subdivided into the sub-populations of individuals under 65 years of age and those that are 65 and older. The resulting two-group heterogeneous model, which was also fitted using the cumulative mortality data for wave C, was also rigorously analysed. Unlike for the case of the one-group model, it was shown, for the two-group model, that vaccine-derived herd immunity can indeed be achieved during Wave C of the pandemic if at least 61% of the populace is fully vaccinated. Thus, this study shows that adding age heterogeneity into a SARS-CoV-2 vaccination model with homogeneous mixing significantly reduces the level of vaccination coverage needed to achieve vaccine-derived herd immunity (specifically, for the heterogeneous model, herd-immunity can be attained during Wave C if a moderate proportion of susceptible individuals are fully vaccinated). The consequence of this result is that vaccination models for SARS-CoV-2 that do not explicitly account for age heterogeneity may be overestimating the level of vaccine-derived herd immunity threshold needed to eliminate the SARS-CoV-2 pandemic.

Association between obstructive sleep apnea (OSA) and COVID-19 severity

Obstructive sleep apnea and sleep-related hypoxia have been associated with higher rates of hospitalization and mortality among patients with Coronavirus disease 2019 (COVID-19). We further explored the association between obstructive sleep apnea, COVID-19 severity and related mortality. In addition, we examined the effects of clinical and demographic parameters on COVID-19. In this retrospective study, we included adult patients who were diagnosed with COVID-19 prior to the Omicron variant identification. We compared the severity of COVID-19 and mortality with the diagnosis of obstructive sleep apnea. The study population included 44,275 patients who tested positive for COVID-19. Of these, 97% had mild or asymptomatic disease, 1.2% had moderate disease, and 1.8% had severe disease. Obstructive sleep apnea was diagnosed in 980 (2.2%) patients. In a multivariate analysis, obstructive sleep apnea diagnosis increased the risk of severe COVID-19 by 1.6 (95% confidence interval: 1.1-2.4) compared with mild disease. However, no increase in mortality was associated with obstructive sleep apnea. Interestingly, patients with moderate and high socioeconomic status had a 1.6 times higher risk for severe COVID-19 than patients from the low socioeconomic status group (95% confidence interval: 1.2-2.1 and 95% confidence interval: 1.1-2.3, respectively). The risk of dying due to COVID-19 was 1.6 (95% confidence interval: 1.1-2.5) and 3.1 (95% confidence interval: 1.8-5.3) times higher in patients with medium and high socioeconomic status, respectively, compared with patients with low socioeconomic status. Diagnosis of obstructive sleep apnea was found to be an independent risk factor for severe COVID-19. The higher the socioeconomic status, the higher the risk of severe COVID-19 morbidity and mortality.

Who is "anti-science"?

Objectives

"Anti-science" accusations are common in medicine and public health, sometimes to discredit scientists who hold opposing views. However, there is no such thing as "one science". Epistemology recognizes that any "science" is sociologically embedded, and therefore contextual and intersubjective. In this paper, we reflect on how "science" needs to adopt various perspectives to give a comprehensive and nuanced understanding of a phenomenon.

Study design

Opinion paper.

Methods

Based on a targeted literature survey, we first clarify the known limits of traditional scientific methods and then reflect on how the scientific reporting about Covid-19 mRNA vaccines has evolved.

Results

The first reports of the Covid-19 mRNA vaccines randomised controlled trial results showed impressive efficacy. Nevertheless, an abundant literature has since depicted a far more nuanced picture of the effectiveness and safety of those vaccines over the medium-term. We organise them around five themes: (i) differentiating between relative and absolute reduction; (ii) taking account of time in reporting effectiveness; (iii) taking account of all outcomes, including adverse effects; (iv) stratifying effectiveness and considering other decision criteria (efficiency, equity, and acceptance); (v) changing the outcome of concern and assessing vaccines' effectiveness on mortality.

Conclusions

Science offers a wide range of perspectives on a given study object. Only the process of deliberation amongst scientists and other stakeholders can result in accepted new knowledge useful to support decision-making. Unfortunately, by trying to reduce "science" to simple messages set in stone, scientists can become the worse enemies of science.

Healthcare workers' attitudes toward and factors influencing their acceptance of an annual COVID-19 booster vaccine: a cross-sectional study in Palestine

BACKGROUND

The emergence of several SARS-CoV-2 variants may necessitate an annual COVID-19 booster vaccine. This study aimed to evaluate healthcare workers' (HCWs) acceptance of a COVID-19 yearly booster vaccine if recommended and its association with their attitudes and burnout levels.

METHODS

We used an online self-administered questionnaire to conduct a cross-sectional study of all HCWs in the West Bank and Gaza Strip of Palestine between August and September 2022. We used the Vaccination Attitudes Examination scale to assess HCWs' vaccination attitudes and the Maslach Burnout Inventory to assess work-related Burnout. In addition, we conducted logistic regression to identify factors independently associated with the acceptance of the booster vaccine.

RESULTS

The study included 919 HCWs; 52.4% were male, 46.5% were physicians, 30.0% were nurses, and 63.1% worked in hospitals. One-third of HCWs (95% CI: 30.5%-36.7%) said they would accept an annual COVID-19 booster vaccine if recommended. HCWs who are suspicious of vaccine benefits [aOR = .70; 95%CI: .65-.75] and those concerned about unforeseeable future effects [aOR = .90; 95%CI: .84-.95] are less likely to accept the booster vaccine if recommended, whereas those who receive annual influenza vaccine are more likely to get it [aOR = 2.9; 95%CI: 1.7-5.0].

CONCLUSION

Only about a third of HCWs would agree to receive an annual COVID-19 booster vaccine if recommended. Mistrust of the vaccine's efficacy and concerns about side effects continue to drive COVID-19 vaccine reluctance. Health officials need to address HCWs' concerns to increase their acceptance of the annual vaccine if it is to be recommended.

Review: N1-methyl-pseudouridine (m1Ψ): Friend or foe of cancer?

Due to the health emergency created by SARS-CoV-2, the virus that causes the COVID-19 disease, the rapid implementation of a new vaccine technology was necessary. mRNA vaccines, being one of the cutting-edge new technologies, attracted significant interest and offered a lot of hope. The potential of these vaccines in preventing admission to hospitals and serious illness in people with comorbidities has recently been called into question due to the vaccines' rapidly waning immunity. Mounting evidence indicates that these vaccines, like many others, do not generate sterilizing immunity, leaving people vulnerable to recurrent infections. Additionally, it has been discovered that the mRNA vaccines inhibit essential immunological pathways, thus impairing early interferon signaling. Within the framework of COVID-19 vaccination, this inhibition ensures an appropriate spike protein synthesis and a reduced immune activation. Evidence is provided that adding 100 % of N1-methyl-pseudouridine (m1Ψ) to the mRNA vaccine in a melanoma model stimulated cancer growth and metastasis, while non-modified mRNA vaccines induced opposite results, thus suggesting that COVID-19 mRNA vaccines could aid cancer development. Based on this compelling evidence, we suggest that future clinical trials for cancers or infectious diseases should not use mRNA vaccines with a 100 % m1Ψ modification, but rather ones with the lower percentage of m1Ψ modification to avoid immune suppression.

Cytokine profiles of mild-to-moderate SARS-CoV-2 infected and recovered pre-vaccinated individuals residing in Indonesia

Background

Accumulating evidence suggests the involvement of cytokine-mediated inflammation, in clinical severity and death related to SARS-CoV-2 infection, especially among pre-vaccinated individuals. An increased risk of death was also described among SARS-CoV-2 recovered individuals, which might be correlated with prolonged inflammatory responses. Despite being among the countries with the highest cumulative deaths due to COVID-19, evidence regarding cytokine profiles among SARS-CoV-2 infected and recovered pre-vaccinated individuals in Indonesia is scarce. Thus, this study aimed to describe the cytokines profiles of pre-vaccinated individuals residing in Indonesia, with mild-to-moderate SARS-CoV-2 infection and those who recovered.

Methods

Sixty-one sera from 24 hospitalized patients with mild-to-moderate SARS-CoV-2 infection, 24 individuals recovered from asymptomatic-to-moderate SARS-CoV-2 infection, and 13 healthy controls unexposed to SARS-CoV-2 were used in this study. Quantification of serum cytokine levels, including IL-6, IL-8, IP-10, TNF-α, CCL-2, CCL-3, CCL-4, and CXCL-13, was performed using a Luminex multi-analyte-profiling (xMAP)-based assay.

Results

The levels of IL-8 along with CCL-2 and CCL-4, were significantly higher (p ≤ 0.01) in hospitalized patients with mild-to-moderate SARS-CoV-2 infection and recovered individuals compared to healthy controls. However, no significant difference was observed in these cytokine levels between infected and recovered individuals. On the other hand, there were no significant differences in several other cytokine levels, including IL-6, IL-10, TNF-α, CCL-3, and CXCL-13, among all groups.

Conclusion

IL-8, CCL-2, and CCL-4 were significantly elevated in pre-vaccinated Indonesian individuals with mild-to-moderate SARS-CoV-2 infection and those who recovered. The cytokine profiles described in this study might indicate inflammatory responses not only among SARS-CoV-2 infected, but also recovered individuals.

The effect of microbiome therapy on COVID-19-induced gut dysbiosis: A narrative and systematic review

AIMS

Emerging evidence highlights the role of COVID-19 in instigating gut dysbiosis, with repercussions on disease severity and bidirectional gut-organ communication involving the lung, heart, brain, and liver. This study aims to evaluate the efficacy of probiotics, prebiotics, synbiotics, and fecal microbiota transplantation (FMT) in addressing gut dysbiosis associated with COVID-19, as well as their impact on related disease severity and clinical outcomes.

MATERIALS AND METHODS

We systematically review 27 studies exploring the efficacy of different microbiome-modulating therapies: probiotics, prebiotics, synbiotics, and fecal microbiota transplantation as potential interventions for COVID-19.

KEY FINDINGS

The probiotics and synbiotics investigated encompassed a spectrum of eight bacterial and fungal genera, namely Lactobacillus, Bifidobacterium, Streptococcus, Enterococcus, Pediococcus, Bacillus, Saccharomyces, and Kluyveromyces. Noteworthy prebiotics employed in these studies included chestnut tannin, galactooligosaccharides, fructooligosaccharides, xylooligosaccharide, and resistant dextrin. The majority of the investigated biotics exhibited positive effects on COVID-19 patients, manifesting in symptom alleviation, inflammation reduction, and notable decreases in mortality rates. Five studies reported death rates, showing an average mortality ranging from 0 % to 11 % in the intervention groups, as compared to 3 % to 30 % in the control groups. Specifically, probiotics, prebiotics, and synbiotics demonstrated efficacy in diminishing the duration and severity of symptoms while significantly accelerating viral and symptomatic remission. FMT emerged as a particularly effective strategy, successfully restoring gut microbiota and ameliorating gastrointestinal disorders.

SIGNIFICANCE

The insights gleaned from this review significantly contribute to our broader comprehension of the therapeutic potential of biotics in addressing COVID-19-related gut dysbiosis and mitigating secondary multi-organ complications.

Comparative Effectiveness of mRNA-1273 and BNT162b2 COVID-19 Vaccines Among Older Adults: Systematic Literature Review and Meta-Analysis Using the GRADE Framework

INTRODUCTION

The mRNA vaccines mRNA-1273 and BNT162b2 demonstrated high efficacy against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in phase 3 clinical trials, including among older adults. To inform coronavirus disease 2019 (COVID-19) vaccine selection, this systematic literature review (SLR) and meta-analysis assessed the comparative effectiveness of mRNA-1273 versus BNT162b2 in older adults.

METHODS

We systematically searched for relevant studies reporting COVID-19 outcomes with mRNA vaccines in older adults aged ≥ 50 years by first cross-checking relevant published SLRs. Based on the cutoff date from a previous similar SLR, we then searched the WHO COVID-19 Research Database for relevant articles published between April 9, 2022, and June 2, 2023. Outcomes of interest were SARS-CoV-2 infection, symptomatic SARS-CoV-2 infection, severe SARS-CoV-2 infection, COVID-19-related hospitalization, and COVID-19-related death following ≥ 2 vaccine doses. Random effects meta-analysis models were used to pool risk ratios (RRs) across studies. Heterogeneity was evaluated using chi-square testing. Evidence certainty was assessed per GRADE framework.

RESULTS

Twenty-four non-randomized real-world studies reporting clinical outcomes with mRNA vaccines in individuals aged ≥ 50 years were included in the meta-analysis. Vaccination with mRNA-1273 was associated with significantly lower risk of SARS-CoV-2 infection (RR 0.72 [95% confidence interval (CI) 0.64‒0.80]), symptomatic SARS-CoV-2 infection (RR 0.72 [95% CI 0.62‒0.83]), severe SARS-CoV-2 infection (RR 0.67 [95% CI 0.57‒0.78]), and COVID-19-related hospitalization (RR 0.65 [95% CI 0.53‒0.79]) but not COVID-19-related death (RR 0.80 [95% CI 0.64‒1.00]) compared with BNT162b2. There was considerable heterogeneity between studies for all outcomes (I2 > 75%) except death (I2 = 0%). Multiple subgroup and sensitivity analyses excluding specific studies generally demonstrated consistent results. Certainty of evidence across outcomes was rated as low (type 3) or very low (type 4), reflecting the lack of randomized controlled trial data.

CONCLUSION

Meta-analysis of 24 observational studies demonstrated significantly lower risk of asymptomatic, symptomatic, and severe infections and hospitalizations with the mRNA-1273 versus BNT162b2 vaccine in older adults aged ≥ 50 years.

Unveiling parental perspectives: COVID-19 vaccination for children in India

Background

Irrespective of the availability of a safe and effective COVID-19 vaccine and its success rate in adults, administering vaccines to children remains a challenge for healthcare workers. Children's vaccine hesitancy among parents remains substantial and is exacerbated due to misleading information. In the present study, we aimed to investigate the hesitancy of parents and their concern about the vaccination and clinical characteristics of COVID-19 in their children.

Methods

A cross-sectional web-based and offline survey comprised of questions about the demographic of children, the status of COVID-19 infection, its severity, vaccination status, sources of information, willingness, concerns and attitude of parents to vaccinate their children against the COVID-19 virus, was conducted. Overall, 846 responses from parents fulfilling the inclusion criteria were analysed by GraphPad Prism 5.

Results

Out of the 846 responses, 51.2% (n = 433) of children were vaccinated against COVID-19. Out of vaccinated children (51.2%), 60.3% (n = 261) had experienced adverse events. Around 21% (n = 98) of children had a history of exposure to the SARS-CoV-2 virus. Among the infected children, 14.3% were asymptomatic and 85.7% had symptoms. Approximately 8% of children had comorbidities, with chronic lung diseases and asthma being the most common. Among the 846 participating parents, 59.5% were mothers and the remaining 40.5% were fathers. A total of 2.7% and 22.2% of parents were found hesitant to administer the COVID-19 vaccine to their children aged 15-18 years and below 15 years, respectively. Among hesitant parents, mothers were found slightly more hesitant as compared to fathers. Also, 35.5% of parents were found hesitant about their own COVID-19 vaccination. Furthermore, the concern for COVID-19 vaccine unwillingness among parents is that a child has already achieved natural immunity after COVID-19 infections (76.8%) followed by vaccine safety and its side effects. The motivating factors to convince parents for their children's COVID-19 vaccination were if their doctors recommend it, followed by detailed information on vaccine side effects and efficacy in children. The most trusted source of information for the parents was found to be the healthcare workers.

Conclusion

These results suggest that data and reviews regarding the safety and efficacy of the COVID-19 vaccine readily available in the public domain could serve as a highly effective strategy for promoting and implementing widespread vaccination among children. By providing easily accessible and comprehensive information, public health authorities can address parental concerns, dispel misconceptions and foster a greater sense of trust in the vaccination process.

ution of the data and methods in real-world COVID-19 vaccine effectiveness studies on mortality: a oping eview protocol

BACKGROUND

Early evidence on COVID-19 vaccine efficacy came from randomised trials. Many important questions subsequently about vaccine effectiveness (VE) have been addressed using real-world studies (RWS) and have informed most vaccination policies globally. As the questions about VE have evolved during the pandemic so have data, study design, and analytical choices. This scoping review aims to characterise this evolution and provide insights for future pandemic planning-specifically, what kinds of questions are asked at different stages of a pandemic, and what data infrastructure and methods are used?

METHODS AND ANALYSIS

We will identify relevant studies in the Johns Hopkins Bloomberg School of Public Health VIEW-hub database, which curates both published and preprint VE RWS identified from PubMed, Embase, Scopus, Web of Science, the WHO COVID Database, MMWR, Eurosurveillance, medRxiv, bioRxiv, SSRN, Europe PMC, Research Square, Knowledge Hub, and Google. We will include RWS of COVID-19 VE that reported COVID-19-specific or all-cause mortality (coded as 'death' in the 'effectiveness studies' data set).Information on study characteristics; study context; data sources; design and analytic methods that address confounding will be extracted by single reviewer and checked for accuracy and discussed in a small group setting by methodological and analytic experts. A timeline mapping approach will be used to capture the evolution of this body of literature.By describing the evolution of RWS of VE through the COVID-19 pandemic, we will help identify options for VE studies and inform policy makers on the minimal data and analytic infrastructure needed to support rapid RWS of VE in future pandemics and of healthcare strategies more broadly.

ETHICS AND DISSEMINATION

As data is in the public domain, ethical approval is not required. Findings of this study will be disseminated through peer-reviewed publications, conference presentations, and working-papers to policy makers.

REGISTRATION

https://doi.org/10.17605/OSF.IO/ZHDKR.

Safety and efficacy of RCP recombinant spike protein covid-19 vaccine compared to Sinopharm BBIBP: A phase III, non-inferiority trial

Background

We conducted a phase III, non-inferiority trial comparing safety and efficacy of RCP recombinant spike protein Covid-19 vaccine to BBIBP (Sinopharm).

Methods

Adult Iranian population received RCP or BBIBP in a randomized, double blind and an additional non-randomized open labeled trial arms. Eligible participants signed a written informed consent and received two intramuscular injections three weeks apart. In the randomized arm, an intranasal dose of vaccine or adjuvant-only preparation were given to the RCP and BBIBP recipients at day 51 respectively. Participants were actively followed for up to 4 months for safety and efficacy outcomes. Primary outcome was PCR + symptomatic Covid-19 disease two weeks after the second dose. The non-inferiority margin was 10% of reported BBIBP vaccine efficacy (HR = 1.36).

Results

We recruited 23,110 participants (7224 in the randomized and 15,886 in the non-randomized arm). We observed 604 primary outcome events during 4 months of active follow-up including 121 and 133 in the randomized and 157 and 193 cases in the non-randomized arms among recipients of RCP and BBIBP respectively. Adjusted hazard ratios for the primary outcome in those receiving RCP compared with BBIBP interval were 0.91 (0.71-1.16) and 0.62 (0.49-0.77) in the randomized and non-randomized arms respectively. The upper boundary of 99.1% confidence interval of HR = 0.91 (0.67-1.22) remained below the margin of non-inferiority in the randomized arm after observing the early stopping rules using O'Brien Fleming method.

Conclusion

Our study showed that the RCP efficacy is non-inferior and its safety profile is comparable to the BBIBP.

Risk of MS relapse and deterioration after COVID-19: A systematic review and meta-analysis

BACKGROUND

Upper respiratory viral infections have long been considered triggers for multiple sclerosis (MS) relapse and exacerbation. The possible effects of SARS-CoV-2 infection on MS relapse and deterioration remain controversial.

METHODS

We systematically searched PubMed, Scopus, Embase, Cochrane, and Web of Science databases to find relevant studies assessing changes in relapse rates or Expanded Disability Status Scale (EDSS) following COVID-19 in people with MS. Meta-analyses were performed, and to investigate sources of heterogeneity, subgroup analysis, meta-regression, and sensitivity analysis were conducted.

RESULTS

We included 14 studies in our systematic review and meta-analysis. The meta-analysis demonstrated that COVID-19 was not associated with a rise in relapse rate (risk ratio (RR): 0.97, 95 % confidence interval (CI): 0.67, 1.41, p-value: 0.87) or a rise in EDSS (standardized mean difference (SMD): -0.09, 95 % CI: -0.22, 0.03, p-value: 0.13). The analysis of EDSS changes indicated a significant heterogeneity (I2: 55 %, p-value: 0.01). Other analyses were not statistically significant.

CONCLUSIONS

COVID-19 infection was not associated with an increased risk of relapse and clinical deterioration in people with MS.

Immediate vs. culture-initiated antibiotic therapy in suspected non-severe ventilator-associated pneumonia: a before-after study (DELAVAP)

BACKGROUND

Ventilator-associated pneumonia (VAP) is the leading nosocomial infection in critical care and is associated with adverse outcomes. When VAP is suspected, starting antibiotic therapy (AT) immediately after pulmonary sampling may expose uninfected patients to unnecessary treatment, whereas waiting for bacteriological confirmation may delay AT in infected patients. As no robust data exist to choose between these strategies, the decision must balance the pre-test diagnostic probability, clinical severity, and risk of antimicrobial resistance. The objective of this study in patients with suspected non-severe VAP was to compare immediate AT started after sampling to conservative AT upon receipt of positive microbiological results. The outcomes were antibiotic sparing, AT suitability, and patient outcomes.

METHODS

This single-center, before-after study included consecutive patients who underwent distal respiratory sampling for a first suspected non-severe VAP episode (no shock requiring vasopressor therapy or severe acute respiratory distress syndrome). AT was started immediately after sampling in 2019 and upon culture positivity in 2022 (conservative strategy). The primary outcome was the number of days alive without AT by day 28. The secondary outcomes were mechanical ventilation duration, day-28 mortality, and AT suitability (active necessary AT or spared AT).

RESULTS

The immediate and conservative strategies were applied in 44 and 43 patients, respectively. Conservative and immediate AT were associated with similar days alive without AT (median [interquartile range], 18.0 [0-21.0] vs. 16.0 [0-20.0], p = 0.50) and without broad-spectrum AT (p = 0.53) by day 28. AT was more often suitable in the conservative group (88.4% vs. 63.6%, p = 0.01), in which 27.9% of patients received no AT at all. No significant differences were found for mechanical ventilation duration (median [95%CI], 9.0 [6-19] vs. 9.0 [6-24] days, p = 0.65) or day-28 mortality (hazard ratio [95%CI], 0.85 [0.4-2.0], p = 0.71).

CONCLUSION

In patients with suspected non-severe VAP, waiting for microbiological confirmation was not associated with antibiotic sparing, compared to immediate AT. This result may be ascribable to low statistical power. AT suitability was better with the conservative strategy. None of the safety outcomes differed between groups. These findings would seem to allow a large, randomized trial comparing immediate and conservative AT strategies.

Are COVID-19 vaccination mandates for healthcare workers effective? A systematic review of the impact of mandates on increasing vaccination, alleviating staff shortages and decreasing staff illness

INTRODUCTION

The rapid development of COVID-19 vaccines is a cornerstone in the global effort to combat the pandemic. Healthcare workers (HCWs), being at the forefront of the pandemic response, have been the focus of vaccine mandate policies. This review aims to evaluate the impacts of COVID-19 vaccine mandates among HCWs, a critical step in understanding the broader implications of such policies in healthcare settings.

OBJECTIVE

The review seeks to synthesize available literature to contribute to greater understanding of the outcomes associated with COVID-19 vaccine mandates for HCWs including vaccine uptake, infection rates, and staffing.

METHODS

A systematic search of relevant literature published from March 2020 to September 2023 was conducted. The Newcastle-Ottawa scale was employed for quality assessment of the included articles. A total of 4,779 publications were identified, with 15 studies meeting the inclusion criteria for the review. A narrative synthesis approach was used to analyze these studies.

RESULTS

COVID-19 vaccine mandates for HCWs were broadly successful in increasing vaccine uptake in most settings. Although the penalties imposed on unvaccinated HCWs did not lead to major disruption of health services, less well-resourced areas may have been more impacted. Furthermore, there is insufficient literature on the impact of the vaccine mandate on reducing SARS-CoV-2 infection among HCWs.

CONCLUSION

COVID-19 vaccine mandates for HCWs have significant implications for public health policy and healthcare management. The findings underscore the need for tailored approaches in mandate policies, considering the specific contexts of healthcare settings and the diverse populations of HCWs. While mandates have shown potential in increasing vaccine uptake with minimal impacts to staffing, more work is needed to investigate the impacts of mandates across various contexts. In addition to these impacts, future research should focus on long-term effects and implications on broader public health strategies.

Impact of Pre-Infection COVID-19 Vaccination on the Incidence and Severity of Post-COVID Syndrome: A Systematic Review and Meta-Analysis

This systematic review critically evaluated the impact of a pre-infection COVID-19 vaccination on the incidence and severity of post-COVID-19 syndrome and aimed to assess the potential protective effect across different vaccines and patient demographics. This study hypothesized that vaccination before infection substantially reduces the risk and severity of post-COVID-19 syndrome. In October 2023, a comprehensive literature search was conducted across three databases, PubMed, Embase, and Scopus, focusing on studies published up to that date. Utilizing a wide array of keywords, the search strategy adhered to the PRISMA guidelines and was registered in the Open Science Framework. The inclusion criteria comprised studies focusing on patients with a breakthrough SARS-CoV-2 infection who developed post-COVID-19 syndrome. We included a total of 13 articles that met the inclusion criteria, analyzing more than 10 million patients with a mean age of 50.6 years, showing that the incidence of intensive care unit (ICU) admissions post-vaccination was as low as 2.4%, with a significant reduction in mortality risk (OR 0.66, 95% CI 0.58-0.74). The prevalence of post-COVID-19 syndrome symptoms was lower in vaccinated individuals (9.5%) compared to unvaccinated (14.6%), with a notable decrease in activity-limiting symptoms (adjusted OR 0.59, 95% CI 0.48-0.73). Vaccinated patients also showed a quicker recovery and return to work (HR 1.37, 95% CI 1.04-1.79). The pooled odds ratio of 0.77 indicates that vaccination is associated with a 23% reduction in the risk of developing post-COVID-19 syndrome (95% CI 0.75-0.79). Despite the protective effects observed, a substantial heterogeneity among the studies was noted. In conclusion, a pre-infection COVID-19 vaccination is associated with a significant reduction in the risk and severity of post-COVID-19 syndrome. However, the observed heterogeneity across studies suggests a need for further research with standardized methods to fully comprehend vaccine efficacy against long COVID.

Second Boost of Omicron SARS-CoV-2 S1 Subunit Vaccine Induced Broad Humoral Immune Responses in Elderly Mice

Currently approved COVID-19 vaccines prevent symptomatic infection, hospitalization, and death from the disease. However, repeated homologous boosters, while considered a solution for severe forms of the disease caused by new SARS-CoV-2 variants in elderly individuals and immunocompromised patients, cannot provide complete protection against breakthrough infections. This highlights the need for alternative platforms for booster vaccines. In our previous study, we assessed the boost effect of the SARS-CoV-2 Beta S1 recombinant protein subunit vaccine (rS1Beta) in aged mice primed with an adenovirus-based vaccine expressing SARS-CoV-2-S1 (Ad5.S1) via subcutaneous injection or intranasal delivery, which induced robust humoral immune responses (1). In this follow-up study, we demonstrated that a second booster dose of a non-adjuvanted recombinant Omicron (BA.1) S1 subunit vaccine with Toll-like receptor 4 (TLR4) agonist RS09 (rS1RS09OM) was effective in stimulating strong S1-specific immune responses and inducing significantly high neutralizing antibodies against the Wuhan, Delta, and Omicron variants in 100-week-old mice. Importantly, the second booster dose elicits cross-reactive antibody responses, resulting in ACE2 binding inhibition against the spike protein of SARS-CoV-2 variants, including Omicron (BA.1) and its subvariants. Interestingly, the levels of IgG and neutralizing antibodies correlated with the level of ACE2 inhibition in the booster serum samples, although Omicron S1-specific IgG level showed a weaker correlation compared to Wuhan S1-specific IgG level. Furthermore, we compared the immunogenic properties of the rS1 subunit vaccine in young, middle-aged, and elderly mice, resulting in reduced immunogenicity with age, especially an impaired Th1-biased immune response in aged mice. Our findings demonstrate that the new variant of concern (VOC) rS1 subunit vaccine as a second booster has the potential to offer cross-neutralization against a broad range of variants and to improve vaccine effectiveness against newly emerging breakthrough SARS-CoV-2 variants in elderly individuals who were previously primed with the authorized vaccines.

Community Level Correlates of COVID-19 Booster Vaccine Hesitancy in the United States: A Cross-Sectional Analysis

Introduction: Evidence exists that individual-level sociodemographic factors contribute to vaccine hesitancy, but it is unknown how community-level factors affect COVID-19 booster dose hesitancy. The current study aims to fill this knowledge gap by comparing data from a nationwide survey on COVID-19 vaccine hesitancy with a community-level indicator, i.e., the Distressed Communities Index (DCI). Methods: Attitudes toward vaccinations, vaccine literacy, COVID-19 vaccine confidence index, and trust were measured using a 48-item, psychometrically valid and reliable survey tool. In this study, 2138 survey participants residing in the United States were divided into quintiles of varying community distress levels based on their zip codes using the DCI. Data were analyzed through Chi-square, one-way ANOVA, and post hoc analysis with Tukey's test. Results: A significantly higher proportion of participants from the distressed communities had lower trust than their prosperous counterparts (26.6% vs. 37.6%, p < 0.001). On the contrary, participants from the prosperous communities had significantly higher vaccine confidence index scores than those in distressed communities (2.22 ± 1.13 vs. 1.70 ± 1.01, p < 0.001). Conclusions: These findings affirm the importance of developing community-level interventions to promote trust in COVID-19 vaccinations and increase booster dose uptake. From these results, future studies can examine the efficacy of various community-level interventions.

Differences in the Evolution of Clinical, Biochemical, and Hematological Indicators in Hospitalized Patients with COVID-19 According to Their Vaccination Scheme: A Cohort Study in One of the World's Highest Hospital Mortality Populations

COVID-19 vaccines primarily prevent severe illnesses or hospitalization, but there is limited data on their impact during hospitalization for seriously ill patients. In a Mexican cohort with high COVID-19 mortality, a study assessed vaccination's effects. From 2021 to 2022, 462 patients with 4455 hospital days were analyzed. The generalized multivariate linear mixed model (GENLINMIXED) with binary logistic regression link, survival analysis and ROC curves were used to identify risk factors for death. The results showed that the vaccinated individuals were almost half as likely to die (adRR = 0.54, 95% CI = 0.30-0.97, p = 0.041). When stratifying by vaccine, the Pfizer group (BNT162b2) had a 2.4-times lower risk of death (adRR = 0.41, 95% CI = 0.2-0.8, p = 0.008), while the AstraZeneca group (ChAdOx1-S) group did not significantly differ from the non-vaccinated (adRR = 1.04, 95% CI = 0.5-2.3, p = 0.915). The Pfizer group exhibited a higher survival, the unvaccinated showed increasing mortality, and the AstraZeneca group remained intermediate (p = 0.003, multigroup log-rank test). Additionally, BNT162b2-vaccinated individuals had lower values for markers, such as ferritin and D-dimer. Biochemical and hematological indicators suggested a protective effect of both types of vaccines, possibly linked to higher lymphocyte counts and lower platelet-to-lymphocyte ratio (PLR). It is imperative to highlight that these results reinforce the efficacy of COVID-19 vaccines. However, further studies are warranted for a comprehensive understanding of these findings.

Seroincidence of SARS-CoV-2 infection prior to and during the rollout of vaccines in a community-based prospective cohort of U.S. adults

This study used repeat serologic testing to estimate infection rates and risk factors in two overlapping cohorts of SARS-CoV-2 N protein seronegative U.S. adults. One mostly unvaccinated sub-cohort was tracked from April 2020 to March 2021 (pre-vaccine/wild-type era, n = 3421), and the other, mostly vaccinated cohort, from March 2021 to June 2022 (vaccine/variant era, n = 2735). Vaccine uptake was 0.53% and 91.3% in the pre-vaccine and vaccine/variant cohorts, respectively. Corresponding seroconversion rates were 9.6 and 25.7 per 100 person-years. In both cohorts, sociodemographic and epidemiologic risk factors for infection were similar, though new risk factors emerged in the vaccine/variant era, such as having a child in the household. Despite higher incidence rates in the vaccine/variant cohort, vaccine boosters, masking, and social distancing were associated with substantially reduced infection risk, even through major variant surges.

Healthcare resource utilisation and costs of hospitalisation and primary care among adults with COVID-19 in England: a population-based cohort study

OBJECTIVES

To quantify direct costs and healthcare resource utilisation (HCRU) associated with acute COVID-19 in adults in England.

DESIGN

Population-based retrospective cohort study using Clinical Practice Research Datalink Aurum primary care electronic medical records linked to Hospital Episode Statistics secondary care administrative data.

SETTING

Patients registered to primary care practices in England.

POPULATION

1 706 368 adults with a positive SARS-CoV-2 PCR or antigen test from August 2020 to January 2022 were included; 13 105 within the hospitalised cohort indexed between August 2020 and March 2021, and 1 693 263 within the primary care cohort indexed between August 2020 and January 2022. Patients with a COVID-19-related hospitalisation within 84 days of a positive test were included in the hospitalised cohort.

MAIN OUTCOME MEASURES

Primary and secondary care HCRU and associated costs ≤4 weeks following positive COVID-19 test, stratified by age group, risk of severe COVID-19 and immunocompromised status.

RESULTS

Among the hospitalised cohort, average length of stay, including critical care stays, was longer in older adults. Median healthcare cost per hospitalisation was higher in those aged 75-84 (£8942) and ≥85 years (£8835) than in those aged <50 years (£7703). While few (6.0%) patients in critical care required mechanical ventilation, its use was higher in older adults (50-74 years: 8.3%; <50 years: 4.3%). HCRU and associated costs were often greater in those at higher risk of severe COVID-19 than in the overall cohort, although minimal differences in HCRU were found across the three different high-risk definitions. Among the primary care cohort, general practitioner or nurse consultations were more frequent among older adults and the immunocompromised.

CONCLUSIONS

COVID-19-related hospitalisations in older adults, particularly critical care stays, were the primary drivers of high COVID-19 resource use in England. These findings may inform health policy decisions and resource allocation in the prevention and management of COVID-19.

Behavioural and social drivers of COVID-19 vaccination in Vietnam: a scoping review

BACKGROUND

Understanding of the behavioural and social drivers (BeSD) of vaccination is key to addressing vaccine hesitancy and accessibility issues. Vietnam's national COVID-19 vaccination programme resulted in high uptake of primary doses among adults, but lower booster doses for adults and primary doses for 5-11 years. This scoping review assessed BeSD influencing COVID-19 vaccine uptake in Vietnam to design interventions on reaching the national vaccination targets.

METHOD

We conducted a scoping review by searching PubMed, MedRxiv, LitCOVID, COVID-19 LOVE platform, WHO's COVID-19 research database and seven dominant Vietnamese language medical journals published in English or Vietnamese between 28 December 2019 and 28 November 2022. Data were narratively synthesised and summarised according to the four components of the WHO BeSD framework. The drivers were then mapped along the timeline of COVID-19 vaccine deployment and the evolution of the pandemic in Vietnam.

RESULTS

We identified 680 records, of which 39 met the inclusion criteria comprising 224 204 participants. Adults' intention to receive COVID-19 vaccines for themselves (23 studies) ranged from 58.0% to 98.1%. Parental intention to vaccinate their under 11-year-old children (six studies) ranged from 32.8% to 79.6%. Key drivers of vaccination uptake were perceived susceptibility and severity of disease, perceived vaccine benefits and safety, healthcare worker recommendation, and positive societal perception. Commonly reported COVID-19 vaccines' information sources (six studies) were social and mainstream media (82%-67%), television (72.7%-51.6%) and healthcare workers (47.5%-17.5%). Key drivers of COVID-19 uptake remained consistent for both adults and children despite changes in community transmission and vaccine deployment.

CONCLUSION

Key enablers of vaccine uptake for adults and children included perceived disease severity, perceived vaccine benefits and safety and healthcare worker recommendations. Future studies should assess vaccine communication targeted to these drivers, national policies and political determinants to optimise vaccine uptake.

Appearance of tolerance-induction and non-inflammatory SARS-CoV-2 spike-specific IgG4 antibodies after COVID-19 booster vaccinations

Background

Understanding the characteristics of the humoral immune responses following COVID-19 vaccinations is crucial for refining vaccination strategies and predicting immune responses to emerging SARS-CoV-2 variants.

Methods

A longitudinal analysis of SARS-CoV-2 spike receptor binding domain (RBD) specific IgG antibody responses, encompassing IgG subclasses IgG1, IgG2, IgG3, and IgG4 was performed. Participants received four mRNA vaccine doses (group 1; n=10) or two ChAdOx1 nCoV-19 and two mRNA booster doses (group 2; n=19) in Bangladesh over two years.

Results

Findings demonstrate robust IgG responses after primary Covishield or mRNA doses; declining to baseline within six months. First mRNA booster restored and surpassed primary IgG responses but waned after six months. Surprisingly, a second mRNA booster did not increase IgG levels further. Comprehensive IgG subclass analysis showed primary Covishield/mRNA vaccination generated predominantly IgG1 responses with limited IgG2/IgG3, Remarkably, IgG4 responses exhibited a distinct pattern. IgG4 remained undetectable initially but increased extensively six months after the second mRNA dose, eventually replacing IgG1 after the 3rd/4th mRNA doses. Conversely, initial Covishield recipients lack IgG4, surged post-second mRNA booster. Notably, mRNA-vaccinated individuals displayed earlier, robust IgG4 levels post first mRNA booster versus Covishield counterparts. IgG1 to IgG4 ratios decreased with increasing doses, most pronounced with four mRNA doses. This study highlights IgG response kinetics, influenced by vaccine type and doses, impacting immunological tolerance and IgG4 induction, shaping future vaccination strategies.

Conclusions

This study highlights the dynamics of IgG responses dependent on vaccine type and number of doses, leading to immunological tolerance and IgG4 induction, and shaping future vaccination strategies.

Looking beyond vaccines: Cultural tightness-looseness moderates the relationship between immunization coverage and disease prevention vigilance

Advancements in vaccination technologies mitigate disease transmission risks but may inadvertently suppress the behavioral immune system, an evolved disease avoidance mechanism. Applying behavioral immune system theory and utilizing robust big data analytics, we examined associations between rising vaccination coverage and government policies, public mobility, and online information seeking regarding disease precautions. We tested whether cultural tightness-looseness moderates the relationship between mass immunization and disease prevention vigilance. Comprehensive time series analyses were conducted using American data (Study 1) and international data (Study 2), employing transfer function modeling, cross-correlation function analysis, and meta-regression analysis. Across both the US and global analyses, as vaccination rates rose over time, government COVID-19 restrictions significantly relaxed, community mobility increased, and online searches for prevention information declined. The relationship between higher vaccination rates and lower disease prevention vigilance was stronger in culturally looser contexts. Results provide initial evidence that mass immunization may be associated with attenuated sensitivity and enhanced flexibility of disease avoidance psychology and actions. However, cultural tightness-looseness significantly moderates this relationship, with tighter cultures displaying sustained vigilance amidst immunization upticks. These findings offer valuable perspectives to inform nuanced policymaking and public health strategies that balance prudent precautions against undue alarm when expanding vaccine coverage worldwide.

Model-informed health and socio-economic benefits of enhancing global equity and access to Covid-19 vaccines

We take a model-informed approach to the view that a global equitable access (GEA) to Covid-19 vaccines is the key to bring this pandemic to an end. We show that the equitable redistribution (proportional to population size) of the currently available vaccines is not sufficient to stop the pandemic, whereas a 60% increase in vaccine access (the global share of vaccinated people) would have allowed the current distribution to stop the pandemic in about a year of vaccination, saving millions of people in poor countries. We then investigate the interplay between access to vaccines and their distribution among rich and poor countries, showing that the access increase to stop the pandemic gets minimized at + 32% by the equitable distribution (- 36% in rich countries and + 60% in poor ones). To estimate the socio-economic benefits of a vaccination campaign with enhanced global equity and access (eGEA), we compare calibrated simulations of the current scenario with a hypothetical, vaccination-intensive scenario that assumes high rollouts (shown however by many rich and poor countries during the 2021-2022 vaccination campaign) and an improved equity from the current 2.5:1 to a 2:1 rich/poor-ratio of the population fractions vaccinated per day. Assuming that the corresponding + 130% of vaccine production is made possible by an Intellectual Property waiver, we show that the money saved on vaccines globally by the selected eGEA scenario overcomes the 5-year profit of the rights holders in the current situation. This justifies compensation mechanisms in exchange for the necessary licensing agreements. The good news is that the benefits of this eGEA scenario are still relevant, were we ready to implement it now.

Persistence of antibody responses to COVID-19 vaccines among participants in the COVID-19 Community Research Partnership

Introduction

High levels of immunity to SARS-CoV-2 in the community correlate with protection from COVID-19 illness. Measuring COVID-19 antibody seroprevalence and persistence may elucidate the level and length of protection afforded by vaccination and infection within a population.

Methods

We measured the duration of detectable anti-spike antibodies following COVID-19 vaccination in a multistate, longitudinal cohort study of almost 13,000 adults who completed daily surveys and submitted monthly dried blood spots collected at home.

Results

Overall, anti-spike antibodies persisted up to 284 days of follow-up with seroreversion occurring in only 2.4% of the study population. In adjusted analyses, risk of seroreversion increased with age (adults aged 55-64: adjusted hazard ratio [aHR] 2.19 [95% confidence interval (CI): 1.22, 3.92] and adults aged > 65: aHR 3.59 [95% CI: 2.07, 6.20] compared to adults aged 18-39). Adults with diabetes had a higher risk of seroreversion versus nondiabetics (aHR 1.77 [95% CI: 1.29, 2.44]). Decreased risk of seroreversion was shown for non-Hispanic Black versus non-Hispanic White (aHR 0.32 [95% CI: 0.13, 0.79]); college degree earners versus no college degree (aHR 0.61 [95% CI: 0.46, 0.81]); and those who received Moderna mRNA-1273 vaccine versus Pfizer-BioNTech BNT162b2 (aHR 0.35 [95% CI: 0.26, 0.47]). An interaction between healthcare worker occupation and sex was detected, with seroreversion increased among male, non-healthcare workers.

Conclusion

We established that a remote, longitudinal, multi-site study can reliably detect antibody durability following COVID-19 vaccination. The survey platform and measurement of antibody response using at-home collection at convenient intervals allowed us to explore sociodemographic factors and comorbidities and identify predictors of antibody persistence, which has been demonstrated to correlate with protection against disease. Our findings may help inform public health interventions and policies to protect those at highest risk for severe illness and assist in determining the optimal timing of booster doses.Clinical trials registry: NCT04342884.

Unraveling the association between vaccine attitude, vaccine conspiracies and self-reported side effects following COVID-19 vaccination among nurses and physicians in Jordan

Background

The negative impact of vaccine conspiracies is linked with negative health behavior. The aim of the current study was to examine the association between attitudes toward booster COVID-19, influenza, and monkeypox (mpox) vaccinations with post-COVID-19 vaccine side effects, vaccine conspiracies, and attitude towards mandatory vaccination among nurses and physicians in Jordan.

Methods

A structured closed-ended questionnaire was used to collect data on demographics, COVID-19 history, COVID-19 vaccine type and doses received, self-reported side effects post-COVID-19 vaccination, acceptance of booster COVID-19, seasonal influenza, and mpox vaccinations, attitudes towards mandatory vaccination, and beliefs in vaccine conspiracies.

Results

The study sample comprised a total of 341 participants. Acceptance of yearly booster COVID-19 vaccination was expressed by 46.6% of the sample, while 73.3% accepted seasonal influenza vaccination, and only 37.0% accepted mpox vaccination. A higher frequency of self-reported side effects following the first COVID-19 vaccine dose was associated with embrace of vaccine conspiracies and vaccine type. For the second vaccine dose, a higher frequency of self-reported side effects was associated with the embrace of vaccine conspiracies, older age, and affiliation to private sector. In multinomial logistic regression analyses, the lower embrace of vaccine conspiracies was associated with lower odds of reporting side effects post-COVID-19 vaccination. The lower embrace of vaccine conspiracies and favorable attitude towards mandatory vaccination were associated with the willingness to get COVID-19, influenza, and mpox vaccinations.

Conclusion

The study findings highlighted the negative impact of embracing vaccine conspiracies on health-seeking behavior among nurses and physicians. The findings indicated that the willingness to get vaccinated was associated with lower endorsement of vaccine conspiracies. Additionally, the lower embrace of vaccine conspiracies was associated with a lower frequency of self-reported side effects following COVID-19 vaccination. These results emphasize the importance of addressing vaccine misinformation and promoting accurate information to ensure optimal vaccine uptake and public health outcomes.

Dose Intervals and Time since Final Dose on Changes in Metabolic Indices after COVID-19 Vaccination

The rapid development and implementation of COVID-19 vaccines merit understanding its effects on metabolic indices. This retrospective longitudinal study investigated the influence of first-to-second-dose intervals and time since the final dose on the metabolic indices of individuals receiving COVID-19 vaccinations. A total of 318 Saudi subjects (59.7% females) aged 12-60 years received COVID-19 vaccines via the national vaccination program. We collected the anthropometric data and fasting blood samples at specific time points before vaccination and after the final vaccination dose, and biochemical metabolic indices, including glucose and lipid profile, were measured. We also collected the dates of vaccination and COVID-19 history during the study period. The participants were stratified into groups based on first-to-second-dose intervals and time since the final dose to compare pre-and post-vaccination changes in metabolic indices between the groups. Logistic regression analysis revealed no differences in pre- to post-vaccination metabolic status between groups based on first-to-second-dose intervals in either adolescents or adults. However, shorter intervals (≤6 months) between the final dose and follow-up were associated with a decrease in total cardiometabolic components, especially triglyceride levels (OR = 0.39, 95% CI: (0.22-0.68), p < 0.001) than longer intervals (>6 months) in adults. In conclusion, time duration since final dose was associated with pre- to post-vaccination changes in metabolic indices, especially triglyceride levels, indicating that post-vaccination improvements wane over time. Further research is needed to validate the observed relationship, as it may contribute to optimizing vaccine effectiveness and safety in the future.

Primary and Recall Immune Responses to SARS-CoV-2 in Breakthrough Infection

Breakthrough infections in SARS-CoV-2 vaccinated individuals are an ideal circumstance for the simultaneous exploration of both the vaccine-induced memory reaction to the spike (S) protein and the primary response to the membrane (M) and nucleocapsid (N) proteins generated by natural infection. We monitored 15 healthcare workers who had been vaccinated with two doses of Pfizer BioNTech BNT162b2 and were then later infected with the SARS-CoV-2 B.1.617.2. (Delta) variant, analysing the antiviral humoral and cellular immune responses. Natural infection determined an immediate and sharp rise in anti-RBD antibody titres and in the frequency of both S-specific antibody secreting cells (ASCs) and memory B lymphocytes. T cells responded promptly to infection by activating and expanding already at 2-5 days. S-specific memory and emerging M- and N-specific T cells both expressed high levels of activation markers and showed effector capacity with similar kinetics but with different magnitude. The results show that natural infection with SARS-CoV-2 in vaccinated individuals induces fully functional and rapidly expanding T and B lymphocytes in concert with the emergence of novel virus-specific T cells. This swift and punctual response also covers viral variants and captures a paradigmatic case of a healthy adaptive immune reaction to infection with a mutating virus.

Epidemiological Characteristics of COVID-19 during Seven Consecutive Epidemiological Waves (2020-2022) in the North Bačka District, Serbia

The COVID-19 pandemic continues to pose a threat to global public health. The purpose of this research was to determine the epidemiological characteristics of COVID-19 in the North Bačka district while observing seven pandemic waves. The cross-sectional study was based on data from the COVID-19 surveillance database of the Institute for Public Health of Vojvodina during the period from March 2020 to December 2022. A total of 38,685 primary infections and 4067 reinfections caused by SARS-CoV-2 were notified. Pandemic waves caused by the Delta variant (cumulative incidence rate of 2482.37/100,000) and by the Omicron variant (cumulative incidence rate of 2994.45/100,000) emerged as significant focal points during the surveillance period. Over the course of three consecutive years (2020-2022), women were more affected (50.11%, 54.03%, and 55.68%, respectively). The highest incidence rates in age-specific categories were recorded in 2021 for the age group 40-49 (1345.32 per 10,000 inhabitants), while in 2022, they shifted towards the elderly population. Regarding vaccination status at the time of diagnosis, in 2021, around 15% of patients were vaccinated, while in 2022, the number increased to 37%. The most widely received vaccine was BBIBP-CorV (67.45%), followed by BNT162b2 (19.81%), Gam-COVID-Vac (9.31%), and ChAdOx1 nCoV-19 (3.42%) vaccine. The implementation of stringent public health measures and their mitigation, together with the emergence of new variants, influenced the dynamics of COVID-19 pandemic waves in the North Bačka district. Notably, throughout the study period, the working-age population was the most affected, along with females, with a mild clinical presentation dominating. Reinfections were most frequently recorded during the latter pandemic waves. Dealing with this pandemic has provided some valuable lessons for the development of future strategies in the case of a similar public health crisis.

Epidemiological characteristics of the three waves of COVID-19 epidemic in Taiwan during April 2022 to March 2023

BACKGROUND

Taiwan experienced a relatively low incidence of COVID-19 before 2022. However, from April 2022 to March 2023, the country was struck by a nationwide outbreak that occurred in three waves. Despite the considerable magnitude of the epidemic, the epidemiological characteristics of this outbreak have yet to be clearly understood.

METHODS

This was a nationwide, population-based, retrospective cohort study. We recruited patients who had been confirmed as domestically-acquired COVID-19 patients from April 17, 2022, to March 19, 2023. The three epidemic waves were analyzed in terms of numbers of cases, cumulative incidence, numbers of COVID-19-related deaths, mortality, gender, age, residence, SARS-CoV-2 variant sub-lineages, and reinfection status.

RESULTS

The numbers of COVID-19 patients (cumulative incidence per million population) were 4,819,625 (207,165.3) in the first wave, 3,587,558 (154,206.5) in the second wave, and 1,746,698 (75,079.5) in the third wave, showing a progressive decline. The numbers of COVID-19-related deaths and mortalities also decreased throughout the three waves. The coverage of vaccination was observed to increase over time.

CONCLUSION

During the three waves of COVID-19 epidemic, the numbers of cases and deaths gradually declined, while the vaccine coverage increased. It may be appropriate to consider easing restrictions and returning to normality. However, continued monitoring of the epidemiological situation and tracking the emergence of new variants are crucial to prevent the possibility of another epidemic.

Identifying Predominant Causes of Death Among Hospitalized COVID-19 Patients During Poland's Second and Third Waves

BACKGROUND Number of confirmed COVID-19 deaths per million population in Poland between November 2020 and May 2021 was one of the largest in Europe. This retrospective study was conducted at a single center in Poland between November 2020 and May 2021to evaluate the morbidity and mortality rates in 581 patients hospitalized with COVID-19. MATERIAL AND METHODS A retrospective single-center study was conducted in a dedicated COVID-19 hospital from November, 2020 to May, 2021. The data of 581 hospitalized patients were analyzed. Multimorbidity was assessed using the Charlson Comorbidity Index, including chronic kidney, respiratory, cardiovascular diseases, diabetes mellitus, cancer, and dementia. The observation period covered admission to the hospital for severe COVID-19 until discharge or death. Diagnosis of COVID-19 was confirmed by quantitative reverse transcription polymerase chain reaction test. Statistical analysis was carried out in the IBM SPSS Statistics program. RESULTS The mortality rate was 35% of all admitted patients. Lung damage was the cause of death in 60%, bacterial superinfection in 26%, arterial thrombosis or thromboembolism in 9%, and heart failure in 5% of patients. The chi-square test showed a significant relationship between sex and the cause of death related to COVID-19 pneumonia and bacterial ventilator-associated pneumonia (VAP). CONCLUSIONS The findings from this study supports findings from other countries that between November 2020 and May 2021, before SARS-CoV-2 vaccination programs were fully implemented and before effective medications and antiviral agents were developed, patients with severe COVID-19 had high rates of morbidity and mortality.

Seroincidence of SARS-CoV-2 infection prior to and during the rollout of vaccines in a community-based prospective cohort of U.S. adults

Background

Infectious disease surveillance systems, which largely rely on diagnosed cases, underestimate the true incidence of SARS-CoV-2 infection, due to under-ascertainment and underreporting. We used repeat serologic testing to measure N-protein seroconversion in a well-characterized cohort of U.S. adults with no serologic evidence of SARS-CoV-2 infection to estimate the incidence of SARS-CoV-2 infection and characterize risk factors, with comparisons before and after the start of the SARS-CoV-2 vaccine and variant eras.

Methods

We assessed the incidence rate of infection and risk factors in two sub-groups (cohorts) that were SARS-CoV-2 N-protein seronegative at the start of each follow-up period: 1) the pre-vaccine/wild-type era cohort (n=3,421), followed from April to November 2020; and 2) the vaccine/variant era cohort (n=2,735), followed from November 2020 to June 2022. Both cohorts underwent repeat serologic testing with an assay for antibodies to the SARS-CoV-2 N protein (Bio-Rad Platelia SARS-CoV-2 total Ab). We estimated crude incidence and sociodemographic/epidemiologic risk factors in both cohorts. We used multivariate Poisson models to compare the risk of SARS-CoV-2 infection in the pre-vaccine/wild-type era cohort (referent group) to that in the vaccine/variant era cohort, within strata of vaccination status and epidemiologic risk factors (essential worker status, child in the household, case in the household, social distancing).

Findings

In the pre-vaccine/wild-type era cohort, only 18 of the 3,421 participants (0.53%) had ≥1 vaccine dose by the end of follow-up, compared with 2,497/2,735 (91.3%) in the vaccine/variant era cohort. We observed 323 and 815 seroconversions in the pre-vaccine/wild-type era and the vaccine/variant era and cohorts, respectively, with corresponding incidence rates of 9.6 (95% CI: 8.3-11.5) and 25.7 (95% CI: 24.2-27.3) per 100 person-years. Associations of sociodemographic and epidemiologic risk factors with SARS-CoV-2 incidence were largely similar in the pre-vaccine/wild-type and vaccine/variant era cohorts. However, some new epidemiologic risk factors emerged in the vaccine/variant era cohort, including having a child in the household, and never wearing a mask while using public transit. Adjusted incidence rate ratios (aIRR), with the entire pre-vaccine/wild-type era cohort as the referent group, showed markedly higher incidence in the vaccine/variant era cohort, but with more vaccine doses associated with lower incidence: aIRRun/undervaccinated=5.3 (95% CI: 4.2-6.7); aIRRprimary series only=5.1 (95% CI: 4.2-7.3); aIRRboosted once=2.5 (95% CI: 2.1-3.0), and aIRRboosted twice=1.65 (95% CI: 1.3-2.1). These associations were essentially unchanged in risk factor-stratified models.

Interpretation

In SARS-CoV-2 N protein seronegative individuals, large increases in incidence and newly emerging epidemiologic risk factors in the vaccine/variant era likely resulted from multiple co-occurring factors, including policy changes, behavior changes, surges in transmission, and changes in SARS-CoV-2 variant properties. While SARS-CoV-2 incidence increased markedly in most groups in the vaccine/variant era, being up to date on vaccines and the use of non-pharmaceutical interventions (NPIs), such as masking and social distancing, remained reliable strategies to mitigate the risk of SARS-CoV-2 infection, even through major surges due to immune evasive variants. Repeat serologic testing in cohort studies is a useful and complementary strategy to characterize SARS-CoV-2 incidence and risk factors.

Cell-mediated and Neutralizing Antibody Responses to the SARS-CoV-2 Omicron BA.4/BA.5-adapted Bivalent Vaccine Booster in Kidney and Liver Transplant Recipients

Background

The immunogenicity elicited by the Omicron BA.4/BA.5-adapted bivalent booster vaccine after solid organ transplantation (SOT) has not been characterized.

Methods

We assessed cell-mediated and neutralizing IgG antibody responses against the BA.4/BA.5 spike receptor-binding domain at baseline and 2 wk after the administration of an mRNA-based bivalent (ancestral strain and BA.4/BA.5 subvariants) vaccine among 30 SOT recipients who had received ≥3 monovalent vaccine doses. Previous coronavirus disease 2019 history was present in 46.7% of them. We also recruited a control group of 19 nontransplant healthy individuals. Cell-mediated immunity was measured by fluorescent ELISpot assay for interferon (IFN)-γ secretion, whereas the neutralizing IgG antibody response against the BA.4/BA.5 spike receptor-binding domain was quantified with a competitive ELISA.

Results

The median number of BA.4/BA.5 spike-specific IFN-γ-producing spot-forming units (SFUs) increased from baseline to 2 wk postbooster (83.8 versus 133.0 SFUs/106 peripheral blood mononuclear cells; P = 0.0017). Seropositivity rate also increased (46.7%-83.3%; P = 0.001), as well as serum neutralizing activity (4.2%-78.3%; P < 0.0001). Patients with no prior coronavirus disease 2019 history experienced higher improvements in cell-mediated and neutralizing responses after booster vaccination. There was no correlation between BA.4/BA.5 spike-specific IFN-γ-producing SFUs and neutralizing activity. Nontransplant controls showed more robust postbooster cell-mediated immunity than SOT recipients (591.1 versus 133.0 IFN-γ-producing SFUs/106 peripheral blood mononuclear cells; P < 0.0001), although no differences were observed for antibody responses in terms of postbooster seropositivity rates or neutralizing activity.

Conclusions

Booster with the BA.4/BA.5-adapted bivalent vaccine generated strong subvariant-specific responses among SOT recipients. Booster-induced cell-mediated immunity, however, remained lower than in immunocompetent individuals.

Ethnic inequalities in positive SARS-CoV-2 tests, infection prognosis, COVID-19 hospitalisations and deaths: analysis of 2 years of a record linked national cohort study in Scotland

BACKGROUND

This study aims to estimate ethnic inequalities in risk for positive SARS-CoV-2 tests, COVID-19 hospitalisations and deaths over time in Scotland.

METHODS

We conducted a population-based cohort study where the 2011 Scottish Census was linked to health records. We included all individuals ≥ 16 years living in Scotland on 1 March 2020. The study period was from 1 March 2020 to 17 April 2022. Self-reported ethnic group was taken from the census and Cox proportional hazard models estimated HRs for positive SARS-CoV-2 tests, hospitalisations and deaths, adjusted for age, sex and health board. We also conducted separate analyses for each of the four waves of COVID-19 to assess changes in risk over time.

FINDINGS

Of the 4 358 339 individuals analysed, 1 093 234 positive SARS-CoV-2 tests, 37 437 hospitalisations and 14 158 deaths occurred. The risk of COVID-19 hospitalisation or death among ethnic minority groups was often higher for White Gypsy/Traveller (HR 2.21, 95% CI (1.61 to 3.06)) and Pakistani 2.09 (1.90 to 2.29) groups compared with the white Scottish group. The risk of COVID-19 hospitalisation or death following confirmed positive SARS-CoV-2 test was particularly higher for White Gypsy/Traveller 2.55 (1.81-3.58), Pakistani 1.75 (1.59-1.73) and African 1.61 (1.28-2.03) individuals relative to white Scottish individuals. However, the risk of COVID-19-related death following hospitalisation did not differ. The risk of COVID-19 outcomes for ethnic minority groups was higher in the first three waves compared with the fourth wave.

INTERPRETATION

Most ethnic minority groups were at increased risk of adverse COVID-19 outcomes in Scotland, especially White Gypsy/Traveller and Pakistani groups. Ethnic inequalities persisted following community infection but not following hospitalisation, suggesting differences in hospital treatment did not substantially contribute to ethnic inequalities.

The barriers, facilitators and association of vaccine certificates on COVID-19 vaccine uptake: a scoping review

BACKGROUND

Globally, COVID-19 vaccines have proven to be instrumental for promoting population health by reducing illness from SARS-CoV-2. Vaccine certificates emerged as a potentially promising solution for encouraging vaccination and facilitating the safe reopening of society, however, they were controversial due to criticisms of infringing upon individual rights. While there is extensive literature describing the ethical, legal, and public health implications of vaccine certificates, there is currently a gap in knowledge about the association of vaccine certificates on vaccine uptake during the COVID-19 pandemic and barriers and facilitators to their use.

OBJECTIVES

The objectives of this scoping review are to (i) describe the existing literature on the association of vaccine certificates on the rates of COVID-19 vaccine uptake across several countries and (ii) describe the intrinsic and extrinsic barriers or facilitators that moderate this relationship.

METHODS

We conducted a scoping review based on PRISMA Extension for Scoping Reviews (PRSIMA-ScR) guidelines. We searched three bibliographic databases (APA PsychInfo, Embase Classic + Embase, OVID-Medline) and preprint severs during the first week of July 2023. Three reviewers independently screened the studies based on pre-specified eligibility criteria and performed quality assessments of the primary literature and data extraction.

RESULTS

Sixteen studies met the inclusion criteria. 14 or these were surveys and 2 were modelling studies. The majority documented that vaccine certificates were significantly associated with increased rates of COVID-19 vaccine uptake (n = 12), motivated by factors such as travel/employer requirements, influence from the government/peers, and trust in the safety, efficacy, and science behind COVID-19 vaccines. Three studies had non-significant or mixed findings. Only one study found a significant decrease in COVID-19 vaccine uptake, motivated by pervasive distrust in the QR code-based system of digital vaccine certificates in Russia. Quality of survey studies was generally high.

CONCLUSION

Our findings provide insights into the existing literature on vaccine certificates association with vaccine uptake in several different jurisdictions and barriers and facilitators to their uptake. This information can be used to guide future examinations of the implementation of vaccine certificates and more effective implementations.

Association of IFNAR2 rs2236757 and OAS3 rs10735079 Polymorphisms with Susceptibility to COVID-19 Infection and Severity in Palestine

The clinical course and severity of COVID-19 vary among patients. This study aimed to investigate the potential correlation between the gene polymorphisms of the interferon receptor (IFNAR2) rs2236757 and oligoadenylate synthetase 3 (OAS3) rs10735079 with the risk of COVID-19 infection and its severity among Palestinian patients. The study was conducted between April and May 2021 on 154 participants who were divided into three groups: the control group (RT-PCR-negative, n = 52), the community cases group (RT-PCR-positive, n = 70), and the critically ill cases (ICU group; n = 32). The genotyping of the investigated polymorphisms was performed using amplicon-based next-generation sequencing. The genotypes distribution for the IFNAR2 rs2236757 was significantly different among the study groups (P = 0.001), while no statistically significant differences were found in the distribution of genotypes for the OAS3 rs10735079 (P = 0.091). Logistic regression analysis adjusted for possible confounding factors revealed a significant association between the risk allele rs2236757A and critical COVID-19 illness (P  <  0.025). Among all patients, those who carried the rs2236757GA were more likely to have a sore throat (OR, 2.52 (95% CI 1.02-6.24); P = 0.011); the presence of the risk allele rs2236757A was associated with an increased risk to dyspnea (OR, 4.70 (95% CI 1.80-12.27); P  <  0.001), while the rs10735079A carriers were less likely to develop muscle aches (OR, 0.34 (95% CI 0.13-0.88); P = 0.0248) and sore throat (OR, 0.17 (95% CI 0.05-0.55); P  <  0.001). In conclusion, our results revealed that the rs2236757A variant was associated with critical COVID-19 illness and dyspnea, whereas the rs10735079A variant was protective for muscle aches and sore throat.

The association between epilepsy and COVID-19: analysis based on Mendelian randomization and FUMA

Objective

A multitude of observational studies have underscored a substantial comorbidity between COVID-19 and epilepsy. This study was aimed at establishing a conclusive causal link between these two conditions.

Methods

We employed Mendelian randomization (MR) to evaluate the causal link between COVID-19 and epilepsy, as well as its focal and generalized subtypes. The GWAS for epilepsy and its subtypes database were abstracted from both FinnGen consortium and ILAE. Additionally, we leveraged functional mapping and annotation (FUMA) to integrate information from genome-wide association studies (GWAS) results.

Results

The MR analyses revealed that genetic liability to COVID-19 infection conferred a causal effect on epilepsy [FinnGen: OR: 1.5306; 95% confidence interval (CI): 1.1676-2.0062, PFDR (false discovery rate) = 0.0076; ILAE: OR: 1.3440; 95% CI: 1.0235-1.7649, PFDR = 0.0429], and generalized epilepsy (FinnGen: OR: 2.1155; 95% CI: 1.1734-3.8139, PFDR = 0.0327; ILAE: OR: 1.1245; 95% CI: 1.0444-1.2108, PFDR = 0.0114). Genetic liability to COVID-19 hospitalization conferred a causal effect on epilepsy (FinnGen: OR: 1.0934; 95% CI: 1.0097-1.1841, PFDR = 0.0422; ILAE: OR: 1.7381; 95% CI: 1.0467-2.8862, PFDR = 0.0451), focal epilepsy (ILAE: OR: 1.7549; 95% CI: 1.1063-2.7838, PFDR = 0.0338), and generalized epilepsy (ILAE: OR: 1.1827; 95% CI: 1.0215-1.3693, PFDR = 0.0406). Genetic liability to COVID-19 severity conferred a causal effect on epilepsy (FinnGen consortium: OR: 1.2454; 95% CI: 1.0850-1.4295, PFDR = 0.0162; ILAE: OR: 1.2724; 95% CI: 1.0347-1.5647, PFDR = 0.0403), focal epilepsy (FinnGen: OR: 1.6818; 95% CI: 1.1478-2.4642, PFDR = 0.0231; ILAE: OR: 1.6598; 95% CI: 1.2572-2.1914, PFDR = 0.0054), and generalized epilepsy (FinnGen: OR: 1.1486; 95% CI: 1.0274-1.2842, PFDR = 0.0335; ILAE: OR: 1.0439; 95% CI: 1.0159-1.0728, PFDR = 0.0086). In contrast, no causal linkage of epilepsy on COVID-19 was observed. Further, FUMA analysis identified six overlapping genes, including SMEK2, PNPT1, EFEMP1, CCDC85A, VRK2, and BCL11A, shared between COVID-19 and epilepsy. Tissue-specific expression analyses revealed that the disease-gene associations of COVID-19 were significantly enriched in lung, ovary, and spleen tissue compartments, while being significantly enriched in brain tissue for epilepsy.

Conclusion

Our study demonstrates that COVID-19 can be a contributing factor to epilepsy, but we found no evidence that epilepsy contributes to COVID-19.

Recognition and Cleavage of Human tRNA Methyltransferase TRMT1 by the SARS-CoV-2 Main Protease

The SARS-CoV-2 main protease (Mpro) is critical for the production of functional viral proteins during infection and, like many viral proteases, can also target host proteins to subvert their cellular functions. Here, we show that the human tRNA methyltransferase TRMT1 can be recognized and cleaved by SARS-CoV-2 Mpro. TRMT1 installs the N2,N2-dimethylguanosine (m2,2G) modification on mammalian tRNAs, which promotes global protein synthesis and cellular redox homeostasis. We find that Mpro can cleave endogenous TRMT1 in human cell lysate, resulting in removal of the TRMT1 zinc finger domain required for tRNA modification activity in cells. Evolutionary analysis shows that the TRMT1 cleavage site is highly conserved in mammals, except in Muroidea, where TRMT1 may be resistant to cleavage. In primates, regions outside the cleavage site with rapid evolution could indicate adaptation to ancient viral pathogens. We determined the structure of a TRMT1 peptide in complex with Mpro, revealing a substrate binding conformation distinct from the majority of available Mpro-peptide complexes. Kinetic parameters for peptide cleavage showed that the TRMT1(526-536) sequence is cleaved with comparable efficiency to the Mpro-targeted nsp8/9 viral cleavage site. Mutagenesis studies and molecular dynamics simulations together indicate that kinetic discrimination occurs during a later step of Mpro-mediated proteolysis that follows substrate binding. Our results provide new information about the structural basis for Mpro substrate recognition and cleavage that could help inform future therapeutic design and raise the possibility that proteolysis of human TRMT1 during SARS-CoV-2 infection suppresses protein translation and oxidative stress response to impact viral pathogenesis.

Inflammatory phenotypes may be more important than age and comorbidities in predicting clinical outcomes in hospitalised patients with COVID-19

Objectives

In critically ill patients with COVID-19, distinct hyperinflammatory and hypoinflammatory phenotypes have been described, with different outcomes and responses to therapy. We investigated if similar phenotypes exist in non-severe illness.

Methods

Consecutive patients with polymerase chain reaction (PCR) confirmed SARS-CoV-2 were examined. Baseline demographics and laboratory investigations were tabulated, including serum C-reactive protein. Patients were divided into those who were hyperinflammatory (defined as C-reactive protein >17 mg/l) or hypoinflammatory. Adverse outcomes, defined as requiring oxygenation, intensive care, or death, were recorded during the hospital stay. Clinical characteristics and outcomes were compared.

Results

Of the 1781 patients examined, 276 (15.5%) had a hyperinflammatory phenotype. They were older (51.8 ± 17.2 vs 40.3 ± 13.8 years, P <0.001), had a lower PCR cycle threshold (PCR cycle threshold value 19.3 ± 6.3 vs 22.7 ± 15.4, P = 0.025) at presentation, and more medical comorbidities. The hyperinflammatory phenotype was independently associated with adverse clinical outcomes, even after adjusting for age, medical history and viral load on multivariable analyses (adjusted odds ratio 5.78, 95% confidence interval 2.86-11.63).

Conclusion

Even in non-severe COVID-19, there are distinct hyper- and hypoinflammatory phenotypes, with the hyperinflammatory phenotype strongly associated with adverse clinical outcomes, that could be distinguished with a simple biomarker.

Primary care physicians' strategies for addressing COVID-19 vaccine hesitancy

OBJECTIVE

To explore the strategies that primary care physicians use to address patient COVID-19 vaccine hesitancy.

METHOD

We administered an online survey to 625 primary care physicians from May 14 to May 25, 2021, to assess the messages that primary care physicians use to encourage hesitant patients to get vaccinated against COVID-19.589 physicians from the total pool of 625 provided open-ended responses. We conducted thematic content analysis on the responses based on previous research and themes identified within the data.

SETTING

The survey was administered online using the survey research firm Dynata.

RESULTS

Eleven primary themes emerged from our analysis, which included, physicians addressing specific concerns about vaccine safety (including costs versus benefits), physicians helping patients understand what it means to remain unvaccinated, or whether physicians try to connect emotionally through the use of guilt, or personal experience, whether physicians use derisive language to communicate with unvaccinated patients. In addition, a small number of physicians indicated they would not attempt to persuade someone who is vaccine hesitant.

CONCLUSIONS

Our study shows that while some of the physicians used different strategies to address vaccine hesitancy, some of the physicians used harsh language or did not make any effort to reduce COVID-19 related vaccine hesitancy among their patients. Focused advocacy and training are needed to increase physician engagement in vaccine-related dialogues with their patients. Such efforts will ensure that critical opportunities for patient education and awareness-building are not missed and ensure high levels of vaccination uptake.

Natural infection versus hybrid (natural and vaccination) humoral immune response to SARS-CoV-2: a comparative paired analysis

Objectives

There is substantial immunological evidence that vaccination following natural infection increases protection. We compare the humoral immune response developed in initially seropositive individuals (naturally infected) to humoral hybrid immune response (developed after infection and vaccination) in the same population group after one year.

Methods

The study included 197 male individuals who were naturally infected with SARS-CoV-2 and then vaccinated with SARS-CoV-2 vaccine. Trimeric spike, nucleocapsid, and ACE2-RBD blocking antibodies for SARS-CoV-2 were measured. Nasal swabs were collected for SARS-CoV-2 PCR testing. Information on vaccination against SARS-CoV-2 and PCR verified infection was retrieved from official databases (Abu Dhabi Health Data Services- SP LLC. ("Malaffi"), including number of vaccine doses received, date of vaccination, and type of the received vaccine.

Results

All the study population were tested PCR-Negative at the time of sample collection. Our results showed that there was a significant rise in the mean (SD) and median (IQR) titers of trimeric spike, nucleocapsid and ACE2-RBD blocking antibodies in the post-vaccination stage. The mean (± SD) and median (IQR) concentration of the anti-S antibody rose by 3.3-fold (+230% ± 197% SD) and 2.8-fold (+185%, 220-390%, p<0.001), respectively. There was an observed positive dose-response relationship between number of the received vaccine doses and having higher proportion of study participants with higher than median concentration in the difference between the measured anti-S and ACE2-RBD blocking antibodies in the post-vaccination compared to pre-vaccination.

Conclusion

Our study demonstrates that COVID-19 vaccination post natural infection elicits a robust immunological response with an impressive rise of SARS-CoV-2 antibodies, especially the ACE2-RBD blocking antibodies.

Are People Willing to Take Regular COVID-19 Vaccines? Prevalence and Determinants of Hesitancy for Regular COVID-19 Vaccination: A Random Population-Based Survey in Hong Kong

The emergence of new coronavirus variants and evidence of waning immunity offered by COVID-19 vaccines draw attention to the need for regular vaccination. Vaccine hesitancy is one of the top ten threats to global health. There is a dearth of knowledge on people's hesitancy to take regular COVID-19 vaccines. This study aimed to investigate the prevalence and determinants of hesitancy for regular COVID-19 vaccination. A population-based, random telephone survey was performed in Hong Kong in April 2022 (n = 1213). The age-standardized hesitancy rate for regular COVID-19 vaccines among Hong Kong adults was 39.4% (95% CI = 35.3-44.1%), exhibiting a sloping S-shape with age. Regression analyses revealed that females, young adults, self-perceived fair/bad health, low COVID-19 vaccine uptake, and believing there are better ways for prevention of infection were positive determinants of hesitancy for regular vaccination. Vaccine confidence, perceived severity and availability, trust in manufacturers and government, and civic duty inclination were negative determinants. Tailored vaccine promotions are needed for females, young adults, and people perceiving poor health and receiving fewer doses. Information on infection severity, vaccine availability, and trust in suppliers, products, and governments are key attitude-change facilitators to decrease hesitancy for regular COVID-19 vaccination and cope with future pandemics.

Factors Associated with Pneumonia in Patients Hospitalized with COVID-19 and the Role of Vaccination

Patients with COVID-19 can develop different forms of the illness with more or less severe symptoms. A 2-year retrospective cohort study was conducted to evaluate the factors associated with the development of pneumonia in patients hospitalized with COVID-19 from March 2020 to February 2022. A total of 385 patients (59.0% males) with a mean age of 69.0 ± 16.0 years were included. At hospital admission, 318 patients (82.6%) reported one or more comorbidities, namely 201 (52.2%) subjects were affected by hypertension, 98 (25.5%) type 2 diabetes, 84 (21.8%) obesity, 36 (9.4%) cancer, and 14 (3.6%) suffered from kidney disease and were being treated with dialysis, and 76 (19.7%) resulted in being vaccinated with a higher prevalence of BNT162b2 vaccine (15.0%). Pneumonia was diagnosed in 276 (71.7%) patients. Multivariate regression analysis showed that pneumonia in COVID-19 patients was positively associated with type 2 diabetes (OR 1.81; 95% CI 1.00-3.27), obesity (OR 2.52; 95% CI 1.27-4.98), and negatively with hypertension (OR 0.58; 95% CI 0.35-0.96). Vaccination against SARS-CoV-2 resulted in a strongly protective factor against the development of pneumonia in COVID-19 patients (OR 0.49; 95% CI 0.28-0.85).

Barriers and shortcomings in access to cardiovascular management and prevention for familial hypercholesterolemia during the COVID-19 pandemic

Familial hypercholesterolemia (FH) is a hereditary condition caused by mutations in the lipid pathway. The goal in managing FH is to reduce circulating low-density lipoprotein cholesterol and, therefore, reduce the risk of developing atherosclerotic cardiovascular disease (ASCVD). Because FH patients were considered high risk groups due to an increased susceptible for contracting COVID-19 infection, we hypothesized whether the effects of the pandemic hindered access to cardiovascular care. In this review, we conducted a literature search in databases Pubmed/Medline and ScienceDirect. We included a comprehensive analysis of findings from articles in English related and summarized the effects of the pandemic on cardiovascular care through direct and indirect effects. During the COVID-19 pandemic, FH patients presented with worse outcomes and prognosis, especially those that have suffered from early ASCVD. This caused avoidance in seeking care due to fear of transmission. The pandemic severely impacted consultations with lipidologists and cardiologists, causing a decline in lipid profile evaluations. Low socioeconomic communities and ethnic minorities were hit the hardest with job displacements and lacked healthcare coverage respectively, leading to treatment nonadherence. Lock-down restrictions promoted sedentary lifestyles and intake of fatty meals, but it is unclear whether these factors attenuated cardiovascular risk in FH. To prevent early atherogenesis in FH patients, universal screening programs, telemedicine, and lifestyle interventions are important recommendations that could improve outcomes in FH patients. However, the need to research in depth on the disproportionate impact within different subgroups should be the forefront of FH research.

Drug delivery breakthrough technologies - A perspective on clinical and societal impact

The way a drug molecule is administered has always had a profound impact on people requiring medical interventions - from vaccine development to cancer therapeutics. In the Controlled Release Society Fall Symposium 2022, a trans-institutional group of scientists from industry, academia, and non-governmental organizations discussed what a breakthrough in the field of drug delivery constitutes. On the basis of these discussions, we classified drug delivery breakthrough technologies into three categories. In category 1, drug delivery systems enable treatment for new molecular entities per se, for instance by overcoming biological barriers. In category 2, drug delivery systems optimize efficacy and/or safety of an existing drug, for instance by directing distribution to their target tissue, by replacing toxic excipients, or by changing the dosing reqimen. In category 3, drug delivery systems improve global access by fostering use in low-resource settings, for instance by facilitating drug administration outside of a controlled health care institutional setting. We recognize that certain breakthroughs can be classified in more than one category. It was concluded that in order to create a true breakthrough technology, multidisciplinary collaboration is mandated to move from pure technical inventions to true innovations addressing key current and emerging unmet health care needs.

Incarcerated in a Pandemic: How COVID-19 Exacerbated the “Pains of Imprisonment”

Although the exact toll of COVID-19 in U.S. prisons and jails is relatively undetermined, estimates show that deaths due to the virus in the nation's correctional facilities are approximately six times higher than deaths in the general population. During the pandemic, jail and prison structures as well as significant overcrowding made it virtually impossible to institute protective measures against infection in correctional settings. Jail and prison administrators suspended in-person visitation, leaving those incarcerated even further isolated, and their friends and family in fear for the health and safety of their loved ones. The present study examines narratives of individuals who spoke about their experiences while incarcerated during the pandemic. The data for the study were gathered from prison reform advocacy organizations that featured individuals’ stories. The narrative findings provide insight into the traumatic experiences that incarcerated people endured, how institutional failures exacerbated their mistrust of the criminal legal system, and their efforts to cope.

Dissecting the Protective Effect of CD8+ T Cells in Response to SARS-CoV-2 mRNA Vaccination and the Potential Link with Lymph Node CD8+ T Cells

SARS-CoV-2 vaccines have played a crucial role in effectively reducing COVID-19 disease severity, with a new generation of vaccines that use messenger RNA (mRNA) technology being administered globally. Neutralizing antibodies have featured as the heroes of vaccine-induced immunity. However, vaccine-elicited CD8⁺ T cells may have a significant impact on the early protective effects of the mRNA vaccine, which are evident 12 days after initial vaccination. Vaccine-induced CD8⁺ T cells have been shown to respond to multiple epitopes of SARS-CoV-2 and exhibit polyfunctionality in the periphery at the early stage, even when neutralizing antibodies are scarce. Furthermore, SARS-CoV-2 mRNA vaccines induce diverse subsets of memory CD8⁺ T cells that persist for more than six months following vaccination. However, the protective role of CD8⁺ T cells in response to the SARS-CoV-2 mRNA vaccines remains a topic of debate. In addition, our understanding of CD8⁺ T cells in response to vaccination in the lymph nodes, where they first encounter antigen, is still limited. This review delves into the current knowledge regarding the protective role of polyfunctional CD8⁺ T cells in controlling the virus, the response to SARS-CoV-2 mRNA vaccines, and the contribution to supporting B cell activity and promoting immune protection in the lymph nodes.

COVID-19 and HIV: Clinical Outcomes among Hospitalized Patients in the United States

The concurrence of HIV and COVID-19 yields unique challenges and considerations for healthcare providers, patients living with HIV, and healthcare systems at-large. Persons living with HIV may face a higher risk of acquiring SARS-CoV-2 infection and experiencing worse clinical outcomes compared to those without. Notably, COVID-19 may have a disproportionate impact on historically disadvantaged populations, including African Americans and those stratified in a lower socio-economic status. Using the National Inpatient Sample (NIS) database, we compared patients with a diagnosis of both HIV and COVID-19 and those who exclusively had a diagnosis of COVID-19. The primary outcome was in-hospital mortality. Secondary outcomes were intubation rate and vasopressor use; acute MI, acute kidney injury (AKI); AKI requiring hemodialysis (HD); venous thromboembolism (VTE); septic shock and cardiac arrest; length of stay; financial burden on healthcare; and resource utilization. A total of 1,572,815 patients were included in this study; a COVID-19-positive sample that did not have HIV (n = 1,564,875, 99.4%) and another sample with HIV and COVID-19 (n = 7940, 0.56%). Patients with COVID-19 and HIV did not have a significant difference in mortality compared to COVID-19 alone (10.2% vs. 11.3%, respectively, p = 0.35); however, that patient cohort did have a significantly higher rate of AKI (33.6% vs. 28.6%, aOR: 1.26 [95% CI 1.13-1.41], p < 0.001). Given the complex interplay between HIV and COVID-19, more prospective studies investigating the factors such as the contribution of viral burden, CD4 cell count, and the details of patients' anti-retroviral therapeutic regimens should be pursued.

Addressing sociodemographic disparities in COVID-19 vaccine uptake among youth in Zimbabwe

INTRODUCTION

COVID-19 vaccine acceptance research has mostly originated from high-income countries and reasons why youth may not get vaccinated may differ in low-income settings. Understanding vaccination coverage across different population groups and the sociocultural influences in healthcare delivery is important to inform targeted vaccination campaigns.

METHODS

A population-based survey was conducted in 24 communities across three provinces (Harare, Bulawayo and Mashonaland East) in Zimbabwe between October 2021 and June 2022. Youth aged 18-24 years were randomly selected using multistage sampling. Sociodemographic characteristics, COVID-19 vaccination uptake and reasons for non-uptake were collected, and odds of vaccination was investigated using logistic regression.

RESULTS

17 682 youth were recruited in the survey (n=10 742, 60.8% female). The median age of participants was 20 (IQR: 19-22) years. Almost two thirds (n=10 652, 60.2%) reported receiving at least one dose of COVID-19 vaccine. A higher proportion of men than women had been vaccinated (68.9% vs 54.7%), and vaccination prevalence increased with age (<19 years: 57.5%, 20-22: 61.5%, >23: 62.2%). Lack of time to get vaccinated, belief that the vaccine was unsafe and anxiety about side effects (particularly infertility) were the main reasons for not getting vaccinated. Factors associated with vaccination were male sex (OR=1.69, 95% CI 1.58 to 1.80), increasing age (>22 years: OR=1.12, 95% CI 1.04 to 1.21), education level (postsecondary: OR=4.34, 95% CI 3.27 to 5.76) and socioeconomic status (least poor: OR=1.32, 95% CI 1.20 to 1.47).

CONCLUSION

This study found vaccine inequity across age, sex, educational attainment and socioeconomic status among youth. Strategies should address these inequities by understanding concerns and tailoring vaccine campaigns to specific groups.

The Efficacy of SARS-CoV-2 Vaccination in the Elderly: A Systemic Review and Meta-analysis

BACKGROUND

Given the reduced immune response to vaccines in older populations, this study aimed to evaluate the efficacy of COVID-19 vaccinations and its impact on breakthrough infection, hospital admission, and mortality in the elderly.

METHODS

We carried out a systemic review and meta-analysis where MEDLINE, Web of Science, EMBASE, ClinicalTrials.gov, and Cochrane Central Register for Controlled Trials were queried to identify relevant literature. We included randomized controlled trials (RCTs), non-randomized trials, prospective, observational cohort, and case-control studies assessing breakthrough infection, hospital admission, and mortality after coronavirus 2 (SARS-CoV-2) vaccination in the elderly (≥ 60 years old).

RESULTS

Overall, 26 studies were included in this meta-analysis. Compared with the unvaccinated group, the vaccinated group showed a decreased risk of SARS-CoV-2 infection after 28-34 (relative risk [RR] = 0.42, 95% confidence interval [CI] 0.37-0.49) and 35-60 days (RR = 0.49, 95% CI 0.37-0.62). There was a step-wise increase in efficacy with additional doses with the two-dose group experiencing decreased risk of breakthrough infection (RR = 0.37, 95% CI 0.32-0.42), hospital admissions (RR = 0.25, 95% CI 0.14-0.45), disease severity (RR = 0.38, 95% CI 0.20-0.70), and mortality (RR = 0.21, 95% CI 0.14-0.32) compared with those receiving one or no doses. Similarly three-dose and four-dose vaccine groups also showed a decreased risk of breakthrough infection (3-dose: RR = 0.14, 95% CI 0.10-0.20; 4-dose RR = 0.46, 95% CI 0.4-0.53), hospital admissions (3-dose: RR = 0.11, 95% CI 0.07-0.17; 4-dose: RR = 0.42, 95% CI 0.32-0.55), and all-cause mortality (3-dose: RR = 0.10, 95% CI 0.02-0.48; 4-dose: RR = 0.48, 95% CI 0.28-0.84) Subgroup analysis found that protection against mortality for vaccinated vs. unvaccinated groups was similar by age (60-79 years: RR = 0.59; 95% CI, 0.47-0.74; ≥ 80 years: RR = 0.76; 95% CI, 0.59-0.98) and gender (female: RR = 0.66; 95% CI, 0.50-0.87, male: (RR = 0.58; 95% CI, 0.44-0.76), and comorbid cardiovascular disease (CVD) (RR = 0.69; 95% CI, 0.52-0.92) or diabetes (DM) (RR = 0.59; 95% CI, 0.39-0.89.

CONCLUSIONS

Our pooled results showed that SARS-CoV-2 vaccines administered to the elderly is effective in preventing prevent breakthrough infection, hospitalization, severity, and death. What's more, increasing number of vaccine doses is becoming increasingly effective.