Background: A safe and effective vaccine against COVID-19 has become a public health priority. However, little is known about the public willingness to accept a future COVID-19 vaccine in China. This study aimed to understand the willingness and determinants for the acceptance of a COVID-19 vaccine among Chinese adults. Methods: A cross-sectional survey using an online questionnaire was conducted in an adult population in China. Chi-square tests were used to identify differences for various intentions regarding COVID-19 vaccination. The t test was used to identify differences among vaccine hesitancy scores. Multivariable logistic regression was used to analyze the predicated factors associated with the willingness to receive a COVID-19 vaccine. Results: Of the 3195 eligible participants, 83.8% were willing to receive a COVID-19 vaccine, and 76.6% believed the vaccine would be beneficial to their health; however, 74.9% expressed concerns or a neutral attitude regarding its potential adverse effects. Of the participants, 76.5% preferred domestically manufactured vaccines and were more willing to be vaccinated than those who preferred imported vaccines. Multivariable logistic regression indicated that lack of confidence, complacency in regard to health, risk of the vaccine, and attention frequency were the main factors affecting the intention to receive a COVID-19 vaccine. Conclusion: Our study indicated that the respondents in China had a high willingness to accept a COVID-19 vaccine, but some participants also worried about its adverse effects. Information regarding the efficacy and safety of an upcoming COVID-19 vaccine should be disseminated to ensure its acceptance and coverage.

Background: Various modalities of vaccines against coronavirus disease 2019 (COVID-19), based on different platforms and immunization procedures, have been successively approved for marketing worldwide. A comprehensive review for clinical trials assessing the safety of COVID-19 vaccines is urgently needed to make an accurate judgment for mass vaccination.Main text: A systematic review and meta-analysis was conducted to determine the safety of COVID-19 vaccine candidates in randomized controlled trials (RCTs). Data search was performed in PubMed, Embase, Cochrane library, Scopus, Web of Science, and MedRxiv. Included articles were limited to RCTs on COVID-19 vaccines. A total of 73,633 subjects from 14 articles were included to compare the risks of adverse events following immunization (AEFI) after vaccinating different COVID-19 vaccines. Pooled risk ratios (RR) of total AEFI for inactivated vaccine, viral-vectored vaccine, and mRNA vaccine were 1.34 [95% confidence interval (CI) 1.11–1.61,P < 0.001], 1.65 (95%CI1.31–2.07,P < 0.001), and 2.01 (95%CI1.78–2.26,P < 0.001), respectively. No significant differences on local and systemic AEFI were found between the first dose and second dose. In addition, people aged ≤ 55 years were at significantly higher risk of AEFI than people aged ≥ 56 years, with a pooledRRof 1.25 (95%CI1.15–1.35,P < 0.001).Conclusions: The safety and tolerance of current COVID-19 vaccine candidates are acceptable for mass vaccination, with inactivated COVID-19 vaccines candidates having the lowest reported AEFI. Long-term surveillance of vaccine safety is required, especially among elderly people with underlying medical conditions.Graphic

With the frequent outbreaks of emerging infectious diseases in recent years, an effective broad-spectrum antiviral drug is becoming an urgent need for global public health. Cholesterol-25-hydroxylase (CH25H) and its enzymatic products 25-hydroxycholesterol (25HC), a well-known oxysterol that regulates lipid metabolism, have been reported to play multiple functions in modulating cholesterol homeostasis, inflammation, and immune responses. CH25H and 25HC were recently identified as exerting broadly antiviral activities, including upon a variety of highly pathogenic viruses such as human immunodeficiency virus (HIV), Ebola virus (EBOV), Nipah virus (NiV), Rift Valley fever virus (RVFV), and Zika virus (ZIKV). The underlying mechanisms for its antiviral activities are being extensively investigated but have not yet been fully clarified. In this study, we summarized the current findings on how CH25H and 25HC play multiple roles to modulate cholesterol metabolism, inflammation, immunity, and antiviral infections. Overall, 25HC should be further studied as a potential therapeutic agent to control emerging infectious diseases in the future.

CD4+ T cell-mediated immunity has increasingly received attention due to its contribution in the control of HIV viral replication; therefore, it is of great significance to improve CD4+ T cell responses to enhance the efficacy of HIV vaccines. Recent studies have suggested that macroautophagy plays a crucial role in modulating adaptive immune responses toward CD4+ T cells or CD8+ T cells. In the present study, a new strategy based on a macroautophagy degradation mechanism is investigated to enhance CD4+ T cell responses against the HIV/SIV gag antigen. Our results showed that when fused to the autophagosome-associated LC3b protein, SIVgag protein can be functionally targeted to autophagosomes, processed by autophagy-mediated degradation in autolysosomes/lysosomes, presented to MHC II compartments and elicit effective potential CD4 T cell responses in vitro. Importantly, compared with the SIVgag protein alone, SIVgag-LC3b fusion antigen can induce a stronger antigen-specific CD4+ T cell response in mice, which is characterized by an enhanced magnitude and polyfunctionality. This study provides insight for the immunological modulation between viral and mammalian cells via autophagy, and it also presents an alternative strategy for the design of new antigens in the development of effective HIV vaccines.