Objective: To evaluate the methodology of the published systematic reviews and Meta-analyses (SR/MA) on efficacy and safety of coronavirus disease 2019 (COVID-19) vaccines. Methods: We conducted a retrieval for literatures published as of December 10, 2021 in English databases (Medline, Embase, Cochrane Library, Web of science) and Chinese databases (CNKI, Wanfang data, VIP, Sinomed). Two reviewers independently screened literatures and extracted data. The methodology of included SR/MA papers was assessed by A MeaSurement Tool to Assess systematic Review-2 (AMSTAR-2) tool in 16 items. Results: A total 22 SR/MA papers were included, in which 3 (13.6%) had low quality and 19 (86.4%) had very low quality. The main problems of these SR/MA included having no definite PICO (Participants, intervention, control and outcome), providing no preliminary research protocol, no list of excluded studies and justify the exclusions, making no evaluation and explanation or discussion of the risk of bias of original studies, no adequate evaluation of publication bias and discuss its likely impact on the results, etc. Conclusion: SR/MA for the efficacy and safety of COVID-19 vaccines had varied methodological deficiencies, further improvements are needed.
COVID-19/prevention & control* ; COVID-19 Vaccines/adverse effects* ; Humans ; Meta-Analysis as Topic ; Systematic Reviews as Topic

During the coronavirus disease 2019 (COVID-19) pandemic, vaccines help control the spread of infection. To date, 47 vaccines have been approved, with another 227 candidates in various stages of development. In the short period of time since the beginning of their use, evidence has begun to emerge of complications following vaccination in the form of the development or exacerbation of a number of pathological conditions (Block et al., 2022; Haseeb et al., 2022). For example, a population-based study in France identified 1612 cases of myocarditis and 1613 cases of pericarditis requiring hospital treatment within five months of vaccination (le Vu et al., 2022).
Humans ; COVID-19/prevention & control* ; COVID-19 Vaccines/adverse effects* ; Vaccination/adverse effects* ; Vitiligo/etiology* ; Thymus Gland/physiopathology*

COVID-19/prevention & control* ; COVID-19 Vaccines/adverse effects* ; Graves Disease ; Humans ; SARS-CoV-2 ; Vaccination/adverse effects*

BACKGROUND: The significant morbidity and mortality resulted from the infection of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) call for urgent development of effective and safe vaccines. We report the immunogenicity and safety of an inactivated SARS-CoV-2 vaccine, KCONVAC, in healthy adults. METHODS: Phase 1 and phase 2 randomized, double-blind, and placebo-controlled trials of KCONVAC were conducted in healthy Chinese adults aged 18 to 59 years. The participants in the phase 1 trial were randomized to receive two doses, one each on Days 0 and 14, of either KCONVAC (5 or 10 μg/dose) or placebo. The participants in the phase 2 trial were randomized to receive either KCONVAC (at 5 or 10 μg/dose) or placebo on Days 0 and 14 (0/14 regimen) or Days 0 and 28 (0/28 regimen). In the phase 1 trial, the primary safety endpoint was the proportion of participants experiencing adverse reactions/events within 28 days following the administration of each dose. In the phase 2 trial, the primary immunogenicity endpoints were neutralization antibody seroconversion and titer and anti-receptor-binding domain immunoglobulin G seroconversion at 28 days after the second dose. RESULTS: In the phase 1 trial, 60 participants were enrolled and received at least one dose of 5-μg vaccine (n = 24), 10-μg vaccine (n = 24), or placebo (n = 12). In the phase 2 trial, 500 participants were enrolled and received at least one dose of 5-μg vaccine (n = 100 for 0/14 or 0/28 regimens), 10-μg vaccine (n = 100 for each regimen), or placebo (n = 50 for each regimen). In the phase 1 trial, 13 (54%), 11 (46%), and seven (7/12) participants reported at least one adverse event (AE) after receiving 5-, 10-μg vaccine, or placebo, respectively. In the phase 2 trial, 16 (16%), 19 (19%), and nine (18%) 0/14-regimen participants reported at least one AE after receiving 5-, 10-μg vaccine, or placebo, respectively. Similar AE incidences were observed in the three 0/28-regimen treatment groups. No AEs with an intensity of grade 3+ were reported, expect for one vaccine-unrelated serious AE (foot fracture) reported in the phase 1 trial. KCONVAC induced significant antibody responses; 0/28 regimen showed a higher immune responses than that did 0/14 regimen after receiving two vaccine doses. CONCLUSIONS: Both doses of KCONVAC are well tolerated and able to induce robust immune responses in healthy adults. These results support testing 5-μg vaccine in the 0/28 regimen in an upcoming phase 3 efficacy trial. TRIAL REGISTRATION http://www.chictr.org.cn/index.aspx (No. ChiCTR2000038804, http://www.chictr.org.cn/showproj.aspx?proj=62350; No. ChiCTR2000039462, http://www.chictr.org.cn/showproj.aspx?proj=63353).
Adult ; COVID-19 ; COVID-19 Vaccines ; Double-Blind Method ; Humans ; SARS-CoV-2 ; Vaccines, Inactivated/adverse effects*

Ongoing global pandemic of Coronavirus Disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has promoted the unprecedented rapid development and large-scale rolling out of different platform-based COVID-19 vaccines worldwide. How to effectively respond to the expected scale increasing adverse events after vaccination campaign of COVID-19 vaccines is a common problem faced by the world. A lot of countries and regions around the world have arranged in advance at different levels, optimizing the original vaccine safety monitoring system from the perspectives of strengthening the foundation and capabilities, promoting internal and external cooperation, upgrading methods, as well as improving transparency and public communication, which has ensured the good and efficient operation of the system and can provide reference for the construction of relevant fields in China.
Humans ; COVID-19/prevention & control* ; COVID-19 Vaccines ; Pandemics/prevention & control* ; SARS-CoV-2 ; Viral Vaccines/adverse effects*

Vaccination is the most effective and feasible way to contain the Coronavirus disease 2019 (COVID-19) pandemic. The rapid development of effective COVID-19 vaccines is an extraordinary achievement. This study reviewed the efficacy/effectiveness, immunogenicity, and safety profile of the 12 most progressed COVID-19 vaccines and discussed the challenges and prospects of the vaccine-based approaches in a global crisis. Overall, most of the current vaccines have shown safety and efficacy/effectiveness during actual clinical trials or in the real-world studies, indicating a development of pandemic control. However, many challenges are faced by pandemic control in terms of maximizing the effect of vaccines, such as rapid vaccine coverage, strategies to address variants with immune escape capability, and surveillance of vaccine safety in the medium- and long-terms.
COVID-19/prevention & control* ; COVID-19 Vaccines/adverse effects* ; Humans ; Pandemics/prevention & control* ; SARS-CoV-2 ; Vaccination

Humans ; COVID-19/prevention & control* ; COVID-19 Vaccines/adverse effects* ; Myocarditis ; SARS-CoV-2 ; Thrombosis/etiology* ; Vaccination

In Singapore, 9.03 million doses of the mRNA COVID-19 vaccines by Pfizer-BioNTech and Moderna have been administered, and 4.46 million people are fully vaccinated. An additional 87,000 people have been vaccinated with vaccines in World Health Organization's Emergency Use Listing. The aim of this review is to explore the reported cardiac adverse events associated with different types of COVID-19 vaccines. A total of 42 studies that reported cardiac side effects after COVID-19 vaccination were included in this study. Reported COVID-19 vaccine-associated cardiac adverse events were mainly myocarditis and pericarditis, most commonly seen in adolescent and young adult male individuals after mRNA vaccination. Reports of other events such as acute myocardial infarction, arrhythmia and stress cardiomyopathy were rare. Outcomes of post-vaccine myocarditis and pericarditis were good. Given the good vaccine efficacy and the high number of cases of infection, hospitalisation and death that could potentially be prevented, COVID-19 vaccine remains of overall benefit, based on the current available data.
Adolescent ; Humans ; Male ; Young Adult ; COVID-19/prevention & control* ; COVID-19 Vaccines/adverse effects* ; Myocarditis/etiology* ; Pericarditis ; RNA, Messenger ; Vaccination/adverse effects*

BACKGROUND: Vaccination has been shown effective in controlling the global coronavirus disease 2019 (COVID-19) pandemic and reducing severe cases. This study was to assess the flare and change in disease activity after COVID-19 vaccination in patients with stable rheumatoid arthritis (RA). METHODS: A prospective cohort of RA patients in remission or with low disease activity was divided into a vaccination group and a non-vaccination group based on their COVID-19 vaccination status. Each of them was examined every 3 to 6 months. In the vaccination group, disease activity was compared before and after vaccination. The rates of flare defined as disease activity scores based on 28-joint count (DAS28) >3.2 with ΔDAS28 ≥0.6 were compared between vaccination and non-vaccination groups. RESULTS: A total of 202 eligible RA patients were enrolled. Of these, 98 patients received no vaccine shot (non-vaccination group), and 104 patients received two doses of vaccine (vaccination group). The median time interval from pre-vaccination visit to the first immunization and from the second dose of vaccine to post-vaccination visit was 67 days and 83 days, respectively. The disease activity scores at pre-vaccination and post-vaccination visits in the vaccination group patients were similar. At enrollment, gender, RA disease course, seropositivity, and disease activity were comparable across the two groups. Flare was observed in five (4.8%) of the vaccination group patients and nine (9.2%) of the non-vaccination group patients at post-vaccination assessment ( P  = 0.221). In terms of safety, 29 (27.9%) patients experienced adverse events (AEs) after vaccination. No serious AEs occurred. CONCLUSIONS COVID-19 vaccinations had no significant effect on disease activity or risk of flare in RA patients in remission or with low disease activity. Patients with stable RA should be encouraged to receive the COVID-19 vaccination.
Humans ; Arthritis, Rheumatoid ; Cohort Studies ; COVID-19/prevention & control* ; COVID-19 Vaccines/adverse effects* ; East Asian People ; Prospective Studies ; Vaccination/adverse effects*

OBJECTIVES: This study aimed to observe the clinical and immune response characteristics of vaccinated persons infected with the delta variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Yangzhou, China. METHODS: We extracted the medical data of 129 patients with delta-variant infection who were admitted to Northern Jiangsu People's Hospital (Yangzhou, China) between August and September, 2021. The patients were grouped according to the number of vaccine doses received into an unvaccinated group: a one-dose group and a two-dose group. The vaccine used was SARS-CoV-2-inactivated vaccine developed by Sinovac. We retrospectively analyzed the patients' epidemiological, clinical, laboratory, and imaging data. RESULTS: Almost all patients with delta-variant infection in Yangzhou were elderly, and patients with severe/critical illness were over 70 years of age. The rates of severe/critical illness (P=0.006), fever (P=0.025), and dyspnea (P=0.045) were lower in the two-dose group than in the unvaccinated group. Compared to the unvaccinated group, the two-dose group showed significantly higher lymphocyte counts and significantly lower levels of C-reactive protein (CRP), interleukin-6 (IL-6), and D-dimer during hospitalization and a significantly higher positive rate of immunoglobulin G (IgG) antibodies at admission (all P<0.05). The cumulative probabilities of hospital discharge and negative virus conversion were also higher in the two-dose group than in the unvaccinated group (P<0.05). CONCLUSIONS Two doses of the SARS-CoV-2-inactivated vaccine were highly effective at limiting symptomatic disease and reducing immune response, while a single dose did not seem to be effective.
Aged ; Aged, 80 and over ; Humans ; COVID-19/prevention & control* ; COVID-19 Vaccines/adverse effects* ; Critical Illness ; Immunity ; Retrospective Studies ; SARS-CoV-2 ; Vaccines, Inactivated/adverse effects* ; Viral Vaccines/adverse effects*