UNASSIGNED: Vaccination against SARS-CoV-2 is an integral pillar of the public health approach to COVID-19. With the emergence of variants of concern that increase transmissibility and escape from vaccine- or infection-induced protection, vaccines have been developed to more closely match the newly circulating SARS-CoV-2 strains to improve protection. The safety and immunogenicity of multiple authorized messenger RNA (mRNA)-based COVID-19 vaccines targeting the omicron sublineage (BA.1, BA.4/BA.5, and XBB.1.5) have been demonstrated in several clinical trials among adults and children.
UNASSIGNED: This review will comprehensively detail the available evidence (published through July 2024) from ongoing clinical trials on omicron variant-containing mRNA-1273 vaccines administered as additional doses in previously vaccinated target demographics.
UNASSIGNED: Across three clinical trials, omicron variant-containing mRNA-1273 vaccines induced immune responses to vaccine-matched omicron strains as well as ancestral SARS-CoV-2, with a safety and reactogenicity profile comparable to the original mRNA-1273 vaccine. Combined with pivotal data demonstrating the safety, efficacy, and effectiveness of the original mRNA-1273 vaccine, these findings support the use of variant-containing mRNA-1273 vaccines and provide confidence that expeditious development of updated vaccines using this established mRNA platform can maintain protection against COVID-19.

In the wake of a global COVID-19 pandemic, where innovations in vaccination technology and the speed of development and distribution have been unprecedented, a wide variety of post-vaccination cutaneous reactions have surfaced. However, there has not been a systematic review that investigates pityriasis eruptions and the associated variants following COVID-19 inoculations. A PubMed search using Preferred Reporting Items for Systematic Reviews and Meta-Analyses was performed to find case reports from the earliest record through November 2022. Data including types of vaccination and pityriasis were extracted and a quality review was performed; 47 reports with 94 patients were found: 64.9% had pityriasis rosea (PR), 3.2% PR-like eruptions, 16.0% pityriasis rubra pilaris, 7.4% pityriasis lichenoides et varioliformis acuta, 3.2% pityriasis lichenoides chronica, and 5.3% had reactions described as atypical. The top three COVID-19 vaccinations reported were Pfizer-BioNTech (47.9%), Oxford-AstraZeneca (11.7%), and Moderna (8.5%). Pityriasis reactivity was reported most frequently after the Pfizer-BioNTech vaccination, with pityriasis rosea being the most common variant. A large difference was additionally found between the ratio of post-vaccination pityriasis reactions following Pfizer and Moderna vaccinations (5.63), and the ratio of Pfizer\'s usage in the United States as of December 28, 2022 relative to that of Moderna (1.59). Further studies with adequate follow-up periods and diagnostic testing will thus need to be performed to elucidate the root of this discrepancy and better characterize the association between different pityriasis reactions and COVID-19 vaccinations.

People living with HIV (PLWH) were not included in the first efficacy studies of mRNA vaccines against SARS-CoV-2. In this literature review, we investigate evidence of humoral and cellular immunity after a third dose of an mRNA vaccine in PLWH. We performed a literature search in PubMed, Embase, Web of Science and SCOPUS published between 1 January 2020 and 31 December 2022. Selection criteria were studies on immunological responses in PLWH, who were given an mRNA-based vaccine as a third vaccine dose against SARS-CoV-2. Eight articles complied with our selection criteria. All studies found a strong humoral response after the third dose. Five studies investigated cellular immunity and found an increased cellular response after the third vaccine dose in PLWH. No difference in humoral response was observed between PLWH and controls after three doses. However, some of the studies suggested a weaker cellular response among PLWH than in controls, which was associated with lower nadir or current CD4+ T-cell counts. In conclusion, we found evidence of strong humoral immunity in PLWH after receiving an mRNA-based COVID-19 vaccine as a third dose, while the cellular immunity may be impaired compared to controls.

BACKGROUND: Prior research indicates that social media is primarily a negative contributor to Covid-19 vaccine outcomes.
OBJECTIVE: The current systematic review of Covid-19 primary series and booster vaccine investigations provides a more nuanced and comprehensive assessment of this association by exploring a) how distinct social media judgments and actions predict different vaccine-related outcomes - perceptions and intentions/uptake, b) both primary series and booster findings, c) types of social media, and d) comparisons across different populations.
METHODS: We conducted a systematic review of published research examining the link between social media and COVID-19 vaccine outcomes - judgments, intentions, and uptake. Overall, we identified 113 published articles.
RESULTS: The findings reveal complex associations between distinct social media predictors and these outcomes. The most consistent negative relationships emerge within studies looking at \'social media as an information source,\' \'trust\', and \'general social media use/passive exposure\' as predictors of less favorable vaccine judgments and intentions/uptake. Conversely, studies focused on \'information seeking\' indicate more mixed results. Among the few booster investigations, there are more positive than negative associations between social media predictors and Covid-19 vaccine intentions. Across different social media platforms and sample populations, social media was a less robust/consistent negative predictor of COVID-19 judgments and intentions.
CONCLUSIONS: While social media can contribute to more negative COVID-19 vaccine judgments and motivations, the consistency of this relationship may vary across populations, the platforms users access, and the nature of exposure. Overall, social media campaigns promoting COVID-19 vaccines should employ distinct strategies to target those individuals that value social media as an information resource.

Coronavirus disease 2019 (COVID-19) continues to be a global health concern, and booster doses are necessary for maintaining vaccine-mediated protection, limiting the spread of severe acute respiratory syndrome coronavirus 2. Despite multiple COVID-19 vaccine options, global booster uptake remains low. Reactogenicity, the occurrence of adverse local/systemic side effects, plays a crucial role in vaccine uptake and acceptance, particularly for booster doses. We conducted a targeted review of the reactogenicity of authorized/approved messenger RNA (mRNA) and protein-based vaccines demonstrated by clinical trials and real-world evidence. It was found that mRNA-based boosters show a higher incidence and an increased severity of reactogenicity compared with the Novavax protein-based COVID-19 vaccine (NVX-CoV2373). In a recent study from the National Institute of Allergy and Infectious Diseases, the incidence of pain/tenderness, swelling, erythema, fatigue/malaise, headache, muscle pain, or fever was higher in individuals boosted with BNT162b2 (0.4% to 41.6% absolute increase) or mRNA-1273 (5.5% to 55.0% absolute increase) compared with NVX-CoV2373. Evidence suggests that NVX-CoV2373, when utilized as a heterologous booster, demonstrates less reactogenicity compared with mRNA vaccines, which, if communicated to hesitant individuals, may strengthen booster uptake rates worldwide. Clinical Trials Registration NCT04889209.

The effectiveness of full Coronavirus Disease 2019 (COVID-19) vaccination against COVID-19 wanes over time. This study aimed to synthesize the clinical effectiveness of the first dose of COVID-19 booster by comparing it to the full vaccination.
Studies in PubMed, Web of Science, Embase, and clinical trials databases were searched from 1 January 2021 to 10 September 2022. Studies were eligible if they comprised general adult participants who were not ever or currently infected with SARS-CoV-2, did not have impaired immunity or immunosuppression, and did not have severe diseases. The seroconversion rate of antibodies to S and S subunits and antibody titers of SARS-CoV-2, frequency, phenotype of specific T and B cells, and clinical events involving confirmed infection, admission to the intensive care unit (ICU), and death were compared between the first booster dose of COVID-19 vaccination group and full vaccination group. The DerSimonian and Laird random effects models were used to estimate the pooled risk ratios (RRs) and corresponding 95% confidence intervals (CIs) for the outcomes of clinical interest. While a qualitative description was mainly used to compare the immunogenicity between the first booster dose of COVID-19 vaccination group and full vaccination group. Sensitivity analysis was used to deal with heterogenicity.
Of the 10,173 records identified, 10 studies were included for analysis. The first dose COVID-19 booster vaccine could induce higher seroconversion rates of antibodies against various SAS-CoV-2 fragments, higher neutralization antibody titers against various SARS-CoV-2 variants, and robust cellular immune response compared to the full vaccination. The risk of SARS-CoV-2 infection, the risk of admission to the ICU, and the risk of death were all higher in the non-booster group than those in the booster group, with RRs of 9.45 (95% CI 3.22-27.79; total evaluated population 12,422,454 vs. 8,441,368; I2 = 100%), 14.75 (95% CI 4.07-53.46; total evaluated population 12,048,224 vs. 7,291,644; I2 = 91%), and 13.63 (95% CI 4.72-39.36; total evaluated population 12,385,960 vs. 8,297,037; I2 = 85%), respectively.
A homogenous or heterogeneous booster COVID-19 vaccination could elicit strong humoral and cellular immune responses to SARS-CoV-2. Furthermore, it could significantly reduce the risk of SARS-CoV-2 infection and severe COVID-19 clinical events on top of two doses. Future studies are needed to investigate the long-term clinical effectiveness of the first booster dose of the COVID-19 vaccine and compare the effectiveness between homogenous and heterogeneous booster COVID-19 vaccination.
https://inplasy.com/inplasy-2022-11-0114/, identifier: INPLASY2022110114.

The exclusion of patients with cancer in clinical trials evaluating COVID-19 vaccine efficacy and safety, in combination with the high rate of severe infections, highlights the need for optimizing vaccination strategies. The aim of this study was to perform a systematic review and meta-analysis of the published available data from prospective and retrospective cohort studies that included patients with either solid or hematological malignancies according to the PRISMA Guidelines. A literature search was performed in the following databases: Medline (Pubmed), Scopus, Clinicaltrials.gov, EMBASE, CENTRAL and Google Scholar. Overall, 70 studies were included for the first and second vaccine dose and 60 studies for the third dose. The Effect Size (ES) of the seroconversion rate after the first dose was 0.41 (95%CI: 0.33-0.50) for hematological malignancies and 0.56 (95%CI: 0.47-0.64) for solid tumors. The seroconversion rates after the second dose were 0.62 (95%CI: 0.57-0.67) for hematological malignancies and 0.88 (95%CI: 0.82-0.93) for solid tumors. After the third dose, the ES for seroconversion was estimated at 0.63 (95%CI: 0.54-0.72) for hematological cancer and 0.88 (95%CI: 0.75-0.97) for solid tumors. A subgroup analysis was performed to evaluate potential factors affecting immune response. Production of anti-SARS-CoV-2 antibodies was found to be more affected in patients with hematological malignancies, which was attributed to the type of malignancy and treatment with monoclonal antibodies according to the subgroup analyses. Overall, this study highlights that patients with cancer present suboptimal humoral responses after COVID-19 vaccination. Several factors including timing of vaccination in relevance with active therapy, type of therapy, and type of cancer should be considered throughout the immunization process.

The rapid rollout of vaccines to combat the coronavirus disease 2019 (COVID-19) pandemic over the past 2 years has resulted in the use of various vaccine platforms and regional differences in COVID-19 vaccine implementation strategies. The aim of this narrative review was to summarize evolving COVID-19 vaccine recommendations in countries in Latin America, Asia, and Africa and the Middle East across various vaccine platforms, age groups, and specific subpopulations. Nuances in primary and booster vaccination schedules were evaluated, and the preliminary impact of such diverse vaccination strategies are discussed, including key vaccine effectiveness data in the era of Omicron-lineage variants. Primary vaccination rates for included Latin American countries were 71-94% for adults and between 41% and 98% for adolescents and children; rates for first booster in adults were 36-85%. Primary vaccination rates for adults in the included Asian countries ranged from 64% in the Philippines to 98% in Malaysia, with corresponding booster rates varying from 9% in India to 78% in Singapore; for adolescents and children, primary vaccination rates ranged from 29% in the Philippines to 93% in Malaysia. Across included African and Middle Eastern countries, primary vaccination rates in adults varied widely from 32% in South Africa to 99% in the United Arab Emirates; booster rates ranged from 5% in South Africa to 60% in Bahrain. Evidence from the regions studied indicates preference of using an mRNA vaccine as a booster on the basis of safety and effectiveness of observed real-world data, especially during circulation of Omicron lineages. Vaccination against COVID-19 remains of paramount importance to reduce the burden of disease; strategies to overcome vaccine inequity, fatigue, hesitancy, and misinformation and to ensure adequate access and supply are also important.

As the COVID-19 pandemic continues and transitions to an endemic stage, booster vaccines will play an important role in personal and public health. However, convincing people to take boosters continues to be a key obstacle. This study systematically analyzed research that examined the predictors of COVID-19 booster vaccine hesitancy. A search of PubMed, Medline, CINAHL, Web of Science, and Scopus uncovered 42 eligible studies. Globally, the average COVID-19 booster vaccination hesitancy rate was 30.72%. Thirteen key factors influencing booster hesitancy emerged from the literature: demographics (gender, age, education, income, occupation, employment status, ethnicity, and marital status), geographical influences (country, region, and residency), adverse events, perceived benefit/efficacy, perceived susceptibility, perceived severity, prior history of COVID-19 infection, vaccination status, vaccination recommendations, health status, knowledge and information, skepticism/distrust/conspiracy theories, and vaccine type. Vaccine communication campaigns and interventions for COVID boosters should focus on factors influencing booster confidence, complacency, and convenience.

COVID-19 vaccines have been highly effective in reducing morbidity and mortality during the pandemic. However, the emergence of the Omicron variant and subvariants as the globally dominant strains have raised doubts about the effectiveness of currently available vaccines and prompted debate about potential future vaccination strategies.
Using the publicly available IVAC VIEW-hub platform, we reviewed 52 studies on vaccine effectiveness (VE) after booster vaccinations. VE were reported for SARS-CoV-2 symptomatic infection, severe disease and death and stratified by vaccine schedule and age. In addition, a non-systematic literature review of safety was performed to identify single or multi-country studies investigating adverse event rates for at least two of the currently available COVID-19 vaccines.
Booster shots of the current COVID-19 vaccines provide consistently high protection against Omicron-related severe disease and death. Additionally, this protection appears to be conserved for at least 3 months, with a small but significant waning after that. The positive risk-benefit ratio of these vaccines is well established, giving us confidence to administer additional doses as required. Future vaccination strategies will likely include a combination of schedules based on risk profile, as overly frequent boosting may be neither beneficial nor sustainable for the general population.