Effectiveness of an inactivated SARS-CoV-2 vaccine in children and adolescents: a large-scale observational study.

Background: Policymakers urgently need evidence to adequately balance the costs and benefits of mass vaccination against COVID-19 across all age groups, including children and adolescents. In this study, we aim to assess the effectiveness of CoronaVac's primary series among children and adolescents in Chile. Methods: We used a large prospective national cohort of about two million children and adolescents 6-16 years to estimate the effectiveness of an inactivated SARS-CoV-2 vaccine (CoronaVac) in preventing laboratory-confirmed symptomatic SARS-CoV-2 infection (COVID-19), hospitalisation, and admission to an intensive care unit (ICU) associated with COVID-19. We compared the risk of individuals treated with a complete primary immunization schedule (two doses, 28 days apart) with the risk of unvaccinated individuals during the follow-up period. The study was conducted in Chile from June 27, 2021, to January 12, 2022, when the SARS-CoV-2 Delta variant was predominant but other variants of concern were co-circulating, including Omicron. We used inverse probability-weighted survival regression models to estimate hazard ratios of complete immunization over the unvaccinated status, accounting for time-varying vaccination exposure and adjusting for relevant demographic, socioeconomic, and clinical confounders. Findings: The estimated adjusted vaccine effectiveness for the inactivated SARS-CoV-2 vaccine in children aged 6-16 years was 74.5% (95% CI, 73.8-75.2), 91.0% (95% CI, 87.8-93.4), 93.8% (95% CI, 87.8-93.4) for the prevention of COVID-19, hospitalisation, and ICU admission, respectively. For the subgroup of children 6-11 years, the vaccine effectiveness was 75.8% (95% CI, 74.7-76.8) for the prevention of COVID-19 and 77.9% (95% CI, 61.5-87.3) for the prevention of hospitalisation. Interpretation: Our results suggest that a complete primary immunization schedule with the inactivated SARS-CoV-2 vaccine provides effective protection against severe COVID-19 disease for children 6-16 years. Funding: Agencia Nacional de Investigación y Desarrollo (ANID) Millennium Science Initiative Program and Fondo de Financiamiento de Centros de Investigación en Áreas Prioritarias (FONDAP).

Characterizing the cellular and molecular variabilities of peripheral immune cells in healthy recipients of BBIBP-CorV inactivated SARS-CoV-2 vaccine by single-cell RNA sequencing.

Over 3 billion doses of inactivated vaccines for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been administered globally. However, our understanding of the immune cell functional transcription and T cell receptor (TCR)/B cell receptor (BCR) repertoire dynamics following inactivated SARS-CoV-2 vaccination remains poorly understood. Here, we performed single-cell RNA and TCR/BCR sequencing on peripheral blood mononuclear cells at four time points after immunization with the inactivated SARS-CoV-2 vaccine BBIBP-CorV. Our analysis revealed an enrichment of monocytes, central memory CD4+ T cells, type 2 helper T cells and memory B cells following vaccination. Single-cell TCR-seq and RNA-seq comminating analysis identified a clonal expansion of CD4+ T cells (but not CD8+ T cells) following a booster vaccination that corresponded to a decrease in the TCR diversity of central memory CD4+ T cells and type 2 helper T cells. Importantly, these TCR repertoire changes and CD4+ T cell differentiation were correlated with the biased VJ gene usage of BCR and the antibody-producing function of B cells post-vaccination. Finally, we compared the functional transcription and repertoire dynamics in immune cells elicited by vaccination and SARS-CoV-2 infection to explore the immune responses under different stimuli. Our data provide novel molecular and cellular evidence for the CD4+ T cell-dependent antibody response induced by inactivated vaccine BBIBP-CorV. This information is urgently needed to develop new prevention and control strategies for SARS-CoV-2 infection. (ClinicalTrials.gov Identifier: NCT04871932).

Impaired Humoral Immunity Identified in Inactivated SARS-CoV-2 Vaccine Recipients without Anti-Spike RBD Antibodies.

Inactivated SARS-CoV-2 vaccines have been deployed in a significant portion of the world population, who have widely varied responses to vaccination. Understanding this differential response would help the development of new vaccines for non-responders. Here, we conducted surveillance of anti-Spike receptor-binding domain (RBD) antibody levels in a large cohort of 534 healthy Chinese subjects vaccinated with two doses of inactivated SARS-CoV-2 vaccines. We show that the positive rate of antibodies among vaccinated subjects rapidly wanes as the interval between antibody testing and vaccination increases (14 to 119 days: 81.03%, 363 of 448 subjects; 120 to 149 days: 46.43%, 13 of 28 subjects; more than 150 days: 20%, 1 of 5 subjects). However, the antibodies were maintained at high levels in 16 convalescent COVID-19 patients at more than 150 days after recovery. We also found that increased age and body mass index are associated with decreased antibody levels. Vaccinated subjects who fail to produce antibodies display impaired B-cell activating humoral immunity, which was confirmed in COVID-19 patients without antibodies detected at 4 to 18 days after diagnosis. IMPORTANCE Our study illustrates the immune responses engaged by encountering antigen, highlighting the critical roles of B-cell activating humoral immunity in the body's antibody production.

Increased body mass index linked to decreased neutralizing antibody titers of inactivated SARS-CoV-2 vaccine in healthcare workers.

Objective: Obesity is an important risk factor for COVID-19. However, whether obesity affects SARS-CoV-2 antibody production is unclear. This study aimed to identify the influence of obesity on neutralizing antibody production of an inactivated SARS-CoV-2 vaccine to better guide vaccination strategies. Methods: This cross-sectional study recruited a total of 239 healthcare workers (age, 21-50 years) from Suining Central Hospital during 22-23 April 2021. An electronic questionnaire on basic characteristics was completed by all participants. A general physical exam and fasting blood sampling by venipuncture were performed. Peripheral leukocyte counts and the ratios of leukocyte subsets, hepatorenal function, and the neutralizing antibody titers against SARS-CoV-2 were measured. Results: Among 239 healthcare workers, the participants with underweight, normal weight, overweight, and obesity accounted for 10.88%, 64.44%, 23.01%, and 1.67%, respectively. The highest peripheral monocyte counts were observed in the group with obesity, whereas the lowest were observed in the group with normal weight. Similar results were obtained with respect to percentage of peripheral monocytes. Participants with obesity had higher peripheral eosinophil counts and percentages than the other three groups. The median neutralizing antibody titer was 12.70 AU/mL, with 85.36% (n = 204) of participants were sufficiently protected against SARS-CoV-2. The lowest neutralizing antibody titers were observed in the group with obesity, whereas the highest were observed in the group that was underweight. Additionally, high BMI was significantly associated with high peripheral monocyte counts [B (95% CI) = 0.008 (0.002, 0.013)] and low neutralizing antibody titers [B (95% CI) = -1.934 (-3.663, -0.206)]. Conclusions: Obesity could induce chronic inflammation, and associated with lower neutralizing antibody titers against SARS-CoV-2 after inactivated SARS-CoV-2 vaccination.

Acute Adverse Events After BNT162b2 mRNA and Inactivated SARS-CoV-2 Vaccines in People who had COVID-19 Vaccines.

Objective: Considering the classical vaccine development processes, COVID-19 vaccines were developed in a concise period. However, safety cannot be compromised for the rapid development of vaccines. Therefore, we aimed to in-vestigate and compare the incidence of acute adverse events between vaccine doses and vaccine types in patients who were previously diagnosed with COVID-19 and those who were not. Method(s): The study was conducted prospectively between July 1, 2021, and October 31, 2021. Participants who were vaccinated with the Pfizer-BioNTech BNT162b2 mRNA COVID-19 vaccine and the Sinovac inactivated SARS-CoV-2 vaccine (CoronaVac) were recruited in the cohort study. The cohort was divided into two vaccine categories and sub-branches: those with COVID-19 in each vaccine category and those without. Eight days after the vaccination, all participants in the cohort were provided with an assessment questionnaire regarding the adverse events they experienced. Result(s): A total of 1607 vaccine doses were followed in the study, 18.7% (n=301) of which were the inactivated SARS-CoV-2 vaccine and 81.3% (n=1306) were the BNT162b2 vaccine. According to the statistics, the risk of developing adverse events with the BNT162b2 vaccine was shown to be 5.8 times higher than the inactivated SARS-CoV-2 vaccine (OR: 5.83;95% CI: 4.34-7.84). In addition, the risk of suffering such adverse events was 1.6 times higher in patients who were previously diagnosed with COVID-19 (OR: 1.61;95% CI: 1.29-2.00) as opposed to patients who were not. Conclusion(s): Based on the results, we can conclude that acute adverse events were more prevalent after vaccination with the BNT162b2 vaccine than the inactivated SARS-CoV-2 vaccine. Furthermore, compared to those who did not have COVID-19, it was evident that patients who were previously diagnosed with COVID-19 were prone to experience mild, temporary, and manageable adverse events. Copyright © 2022, DOC Design and Informatics Co. Ltd.. All rights reserved.

Inactivated whole-virion SARS-CoV-2 vaccines and long-term clinical outcomes in patients with coronary atherosclerosis disease in China: a prospective cohort study.

AIMS: Publicized adverse events after vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) raised concern among patients with coronary atherosclerosis disease (CAD). We sought to study the association between SARS-CoV-2 vaccines and long-term clinical outcomes including ischaemic and bleeding events among patients with CAD. METHODS AND RESULTS: Inpatients diagnosed with CAD by coronary angiography, without a history of SARS-CoV-2 infection and vaccination, were included between 1 January and 30 April 2021, and underwent follow-up until 31 January 2022. Two doses of inactivated whole-virion SARS-CoV-2 vaccine (CoronaVac, BBIBPCorV, or WIBP-CorV) were available after discharge, and the group was stratified by vaccination. The primary composite outcomes were cardiovascular death, non-fatal myocardial infarction, stent thrombosis, unplanned revascularization, ischaemic stroke, venous thrombo-embolism, or peripheral arterial thrombosis. The bleeding outcomes were Bleeding Academic Research Consortium (BARC) type 3 or 5 bleeding. Cox regression models with vaccination status as a time-dependent covariate were used to calculate the hazard ratio (HR) for the outcomes. A propensity score matching method was used to reduce confounding biases. This prospective cohort study included 2078 individuals with CAD, 1021 (49.1%) were vaccinated. During a median follow-up of 9.1 months, 45 (4.3%) primary composite outcomes occurred in the unvaccinated group, and 33 (3.2%) in the vaccinated group. In Cox regression, the adjusted HR was 1.13 [95% confidence interval (CI) 0.65-1.93]. The adjusted HR for the bleeding outcomes associated with vaccination was 0.81 [95% CI 0.35-1.19]. After matching, the adjusted HR for the primary composite outcomes associated with vaccination was 1.06 [95% CI 0.57-1.99] and for the bleeding outcomes was 0.91 [95% CI 0.35-2.38]. Similar results were found in the seven prespecified subgroups. No grade 3 adverse reactions after vaccination were recorded. CONCLUSION: Our results indicated no evidence of an increased ischaemic or bleeding risk after vaccination with inactivated SARS-CoV-2 vaccine among Chinese patients with CAD, with limited statistical power.

Effects of inactivated SARS-CoV-2 vaccination on male fertility: a retrospective cohort study.

BACKGROUND: Numerous studies have revealed severe damage to male fertility from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, raising concerns about the potential adverse impact on reproductive function of the coronavirus disease 2019 (COVID-19) vaccine developed based on the virus. Interestingly, there are several researchers who have studied the impact of the COVID-19 mRNA vaccine since then but have come up with conflicting results. As a near-ideal candidate for mass immunization programs, inactivated SARS-CoV-2 vaccine has been widely used in many countries, particularly in less wealthy nations. However, little is known about its effect on male fertility. METHODS: Here, we conducted a retrospective cohort study at a single large center for reproductive medicine in China between December 2021 and August 2022. 519 fertile men with no history of laboratory-confirmed COVID-19 were included and categorized into four groups based on their vaccination status: unvaccinated group (n=168), one-dose vaccinated group (n=8), fully vaccinated group (n=183), and booster group (n=160). All of them underwent a semen analysis and most had serum sex hormone levels tested. RESULTS: There were no significant differences in all semen parameters and sex hormone levels between the unvaccinated group and either vaccinated group. To account for possible vaccination-to-test interval-specific changes, sub-analyses were performed for two interval groups: ≤90 and >90 days. As expected, most of the semen parameters and sex hormone levels remained unchanged between the control and vaccinated groups. However, participants in vaccinated group (≤90 days) have decreased total sperm motility and increased FSH level compared with the ones in unvaccinated group. Moreover, some trends similar to those found during COVID-19 infection and recovery were observed in our study. Fortunately, all values are within the normal range. In addition, vaccinated participants reported few adverse reactions. No special medical intervention was required, and no serious adverse reactions happened. CONCLUSION: Our study suggests that inactivated SARS-CoV-2 vaccination does not impair male fertility, possibly due to the low frequency of adverse effects. This information reassures young male population who got this vaccine worldwide, and helps guide future vaccination efforts. This article is protected by copyright. All rights reserved.

Acute Adverse Events After BNT162b2 mRNA and Inactivated SARS-CoV-2 Vaccines in People who had COVID-19 Vaccines

Objective: Considering the classical vaccine development processes, COVID-19 vaccines were developed in a concise period. However, safety cannot be compromised for the rapid development of vaccines. Therefore, we aimed to in-vestigate and compare the incidence of acute adverse events between vaccine doses and vaccine types in patients who were previously diagnosed with COVID-19 and those who were not. Method(s): The study was conducted prospectively between July 1, 2021, and October 31, 2021. Participants who were vaccinated with the Pfizer-BioNTech BNT162b2 mRNA COVID-19 vaccine and the Sinovac inactivated SARS-CoV-2 vaccine (CoronaVac) were recruited in the cohort study. The cohort was divided into two vaccine categories and sub-branches: those with COVID-19 in each vaccine category and those without. Eight days after the vaccination, all participants in the cohort were provided with an assessment questionnaire regarding the adverse events they experienced. Result(s): A total of 1607 vaccine doses were followed in the study, 18.7% (n=301) of which were the inactivated SARS-CoV-2 vaccine and 81.3% (n=1306) were the BNT162b2 vaccine. According to the statistics, the risk of developing adverse events with the BNT162b2 vaccine was shown to be 5.8 times higher than the inactivated SARS-CoV-2 vaccine (OR: 5.83;95% CI: 4.34-7.84). In addition, the risk of suffering such adverse events was 1.6 times higher in patients who were previously diagnosed with COVID-19 (OR: 1.61;95% CI: 1.29-2.00) as opposed to patients who were not. Conclusion(s): Based on the results, we can conclude that acute adverse events were more prevalent after vaccination with the BNT162b2 vaccine than the inactivated SARS-CoV-2 vaccine. Furthermore, compared to those who did not have COVID-19, it was evident that patients who were previously diagnosed with COVID-19 were prone to experience mild, temporary, and manageable adverse events. Copyright © 2022, DOC Design and Informatics Co. Ltd.. All rights reserved.

Impacts of delta and omicron variants on inactivated SARS-CoV-2 vaccine-induced T cell responses in patients with autoimmune diseases and healthy controls.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection causes coronavirus disease 2019 (COVID-19), which is still devastating economies and communities globally. The increasing infections of variants of concern (VOCs) in vaccinated population have raised concerns about the effectiveness of current vaccines. Patients with autoimmune diseases (PAD) under immunosuppressant treatments are facing higher risk of infection and potentially lower immune responses to SARS-CoV-2 vaccination. METHODS: Blood samples were collected from PAD or healthy controls (HC) who finished two or three doses of inactivated vaccines. Spike peptides derived from wild-type strain, delta, omicron BA.1 were utilised to evaluate T cell responses and their cross-recognition of delta and omicron in HC and PAD by flow cytometry and ex vivo IFNγ-ELISpot. RESULTS: We found that inactivated vaccine-induced spike-specific memory T cells were long-lasting in both PAD and HC. These spike-specific T cells were highly conserved and cross-recognized delta and omicron. Moreover, a third inactivated vaccine expanded spike-specific T cells that responded to delta and omicron spike peptides substantially in both PAD and HC. Importantly, the polyfunctionality of spike-specific memory T cells was preserved in terms of cytokine and cytotoxic responses. Although the extent of T cell responses was lower in PAD after two-dose, T cell responses were boosted to a greater magnitude in PAD by the third dose, bringing comparable spike-specific T cell immunity after the third dose. CONCLUSION: Inactivated vaccine-induced spike-specific T cells remain largely intact against delta and omicron variants. This study expands our understanding of inactivated vaccine-induced T cell responses in PAD and HC, which could have important indications for vaccination strategy.

Early Humoral Responses of Hemodialysis Patients After Inactivated SARS-CoV-2 Vaccination.

Purpose: To detect antibody responses to inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine in patients undergoing hemodialysis and to investigate vaccine-related adverse events. Patients and Methods: A total of 120 hemodialysis (HD) patients and 24 healthy controls (HCs) who had not been previously infected with SARS-CoV-2 and had received their first dose of the inactivated vaccine (CoronaVac; Sinovac Biotech Ltd) were recruited for this study. All participants were scheduled to receive a second dose of inactivated SARS-CoV-2 vaccine. Serum-specific immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies against the SARS-CoV-2 were detected at least 14 days after the second dose of vaccine using a commercial kit. Positive and negative results were defined as a sample/cutoff (S/CO) ratio≥1.00 and <1.00, respectively. Vaccination-related adverse events were assessed using a standardized questionnaire. Results: There were no significant differences regarding the seroprevalences of IgG and IgM antibodies against SARS-CoV-2 and the self-reported vaccination-related adverse events between HD patients and HCs. The analysis results for HD patients suggest that 82 (68.3%) and 27 (22.5%) tested positive for IgG and IgM, respectively. The levels of IgG were higher than IgM levels (P<0.0001). In addition, the IgG-positive group had significantly higher serum albumin levels than the IgG-negative group (P<0.05). Only mild vaccine-related adverse events were observed in two patients (1.66%) and in one healthy individual (4.2%). Conclusion: The seroprevalences of IgG and IgM antibodies against SARS-CoV-2 and vaccination-related adverse effects are similar between HD and HCs. The inactivated SARS-CoV-2 vaccine is effective and safe in inducing near-term immunity in hemodialysis patients.

Immunogenicity and safety of an inactivated SARS-CoV-2 vaccine (Sinopharm BBIBP-CorV) coadministered with quadrivalent split-virion inactivated influenza vaccine and 23-valent pneumococcal polysaccharide vaccine in China: A multicentre, non-inferiority, open-label, randomised, controlled, phase 4 trial.

BACKGROUND: The safety and immunogenicity of the coadministration of an inactivated SARS-CoV-2 vaccine (Sinopharm BBIBP-CorV), quadrivalent split-virion inactivated influenza vaccine (IIV4), and 23-valent pneumococcal polysaccharide vaccine (PPV23) in adults in China is unknown. METHODS: In this open-label, non-inferiority, randomised controlled trial, participants aged ≥ 18 years were recruited from the community. Individuals were eligible if they had no history of SARS-CoV-2 vaccine or any pneumonia vaccine and had not received an influenza vaccine during the 2020-21 influenza season. Eligible participants were randomly assigned (1:1:1), using block randomization stratified, to either: SARS-CoV-2 vaccine and IIV4 followed by SARS-CoV-2 vaccine and PPV23 (SARS-CoV-2 + IIV4/PPV23 group); two doses of SARS-CoV-2 vaccine (SARS-CoV-2 vaccine group); or IIV4 followed by PPV23 (IIV4/PPV23 group). Vaccines were administered 28 days apart, with blood samples taken on day 0 and day 28 before vaccination, and on day 56. RESULTS: Between March 10 and March 15, 2021, 1152 participants were recruited and randomly assigned to three groups (384 per group). 1132 participants were included in the per-protocol population (375 in the SARS-CoV-2 + IIV4/PPV23 group, 380 in the SARS-CoV-2 vaccine group, and 377 in the IIV4/PPV23 group). The seroconversion rate (100 % vs 100 %) and GMT (159.13 vs 173.20; GMT ratio of 0.92 [95 % CI 0.83 to 1.02]) of SARS-CoV-2 neutralising antibodies in the SARS-CoV-2 + IIV4/PPV23 group was not inferior to those in the SARS-CoV-2 vaccine group. The SARS-CoV-2 + IIV4/PPV23 group was not inferior to the IIV4/PPV23 group in terms of seroconversion rates and GMT of influenza virus antibodies for all strains except for the seroconversion rate for the B/Yamagata strain. The SARS-CoV-2 + IIV4/PPV23 group was not inferior to the IIV4/PPV23 group regarding seroconversion rates and GMC of Streptococcus pneumoniae IgG antibodies specific to all serotypes. All vaccines were well tolerated. CONCLUSIONS: The coadministration of the inactivated SARS-CoV-2 vaccine and IIV4/PPV23 is safe with satisfactory immunogenicity. This study is registered with ClinicalTrials.gov, NCT04790851.

Vaccination with the Inactivated Vaccine (Sinopharm BBIBP-CorV) Ensures Protection against SARS-CoV-2 Related Disease.

Vaccination against coronavirus disease 2019 (COVID-19) has become an important public health solution. Developing a safe and effective vaccine against COVID-19 is a viable long-term solution to control the pandemic. As one of the two inactivated severe acute respiratory syndrome virus 2 (SARS-CoV-2) vaccines developed in China that entered the WHO emergency use list, Sinopharm BBIBP-CorV, an aluminum-hydroxide-adjuvanted, inactivated whole-virus vaccine, has been widely distributed, with more than 400 million doses administered in more than 40 countries. The evidence of the safety, efficacy, and effectiveness of BBIBP-CorV is gathered and reviewed. We further comment on one of the latest papers that disclosed the effectiveness results between BBIBP-CorV, rAd26-rAd5, and ChAdOx1.

The Effect of Inactivated SARS-CoV-2 Vaccines on TRAB in Graves' Disease.

Background: The ongoing coronavirus disease 2019 (COVID-19) pandemic has forced the development of vaccines. Reports have suggested that vaccines play a role in inducing autoimmune diseases (AIDs). Scattered cases have reported that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines may promote thyroid disease, including Graves' disease (GD). However, the effect of inactivated SARS-CoV-2 vaccine on GD remains unclear. The aim of the present study was to investigate the response of thyrotropin receptor antibody (TRAB) to inactivated SARS-COV-2 vaccines. Methods: We conducted a retrospective study to observe the differences in thyroid function and TRAB trends between pre-vaccination (n=412) and post-vaccination (n=231) groups at an interval of 2 months. We then retrospectively observed the differences in serum thyroid function and TRAB levels at 3 months before (n=280), 1 month before (n=294), 1 month after (n=306), and 3 months after (n=250) vaccination. Subsequently, 173 GD patients who were not vaccinated with inactivated SARS-COV-2 vaccines were selected for a prospective study. Thyroid function and TRAB assessment were performed before 3 and 1 months and 1 and 3 months after the first dose of vaccination and were then compared by repeated measures ANOVA to explore their dynamic changes. Results: A retrospective study preliminarily observed that the trend of TRAB post-vaccination was opposite of that pre-vaccination (p=0.000), serum TRAB levels decreased before vaccination and increased after vaccination. In this prospective study, repeated measures ANOVA indicated significant differences in serum FT3 (p=0.000), FT4 (p=0.000), TSH (p=0.000), and TRAB (p=0.000) levels at different time points before and after vaccination. Serum TRAB levels showed dynamic changes that decreased significantly at 1 month before vaccination (p=0.000), no significant differences at 1 month after vaccination (p=0.583), and reflected an upward trend at 3 months after vaccination (p=0.034). Serum FT3 and FT4 levels showed similar trends to serum TRAB levels before and after vaccination. Instead, the serum TSH levels showed a continuous upward trend over time. Conclusion: Based on the results obtained in both retrospective and prospective studies, we concluded that serum TRAB levels decreased less after inactivated SARS-CoV-2 vaccination and showed an upward trend, which may be related to humoral immunity induced by vaccination.

Safety and Immunogenicity of Inactivated and Recombinant Protein SARS-CoV-2 Vaccines in Patients With Thyroid Cancer.

Background: This study aimed at assessing the safety and immunogenicity of SARS-CoV-2 vaccines in patients with thyroid cancer. Methods: This observational study included thyroid cancer patients between April 1, 2021, and November 31, 2021, in the Second Affiliated Hospital of Chongqing Medical University. All participants received at least one dose of the SARS-CoV-2 vaccine. SARS-CoV-2 IgG was tested, and the interval time between the last dose and humoral response test ranged from <1 to 8 months. The complications after SARS-CoV-2 vaccines were recorded. Results: A total of 115 participants at least received one dose of SARS-CoV-2 vaccines with a 67.0% IgG-positive rate. Among them, 98 cases had completed vaccination, and the positivity of SARS-CoV-2 IgG antibodies was 96% (24/25) with three doses of ZF2001. SARS-CoV-2 IgG antibodies' positivity was 63.0% (46/73) of two doses of CoronaVac or BBIBP-CorV vaccine. Additionally, after 4 months of the last-dose vaccination, the IgG-positive rate (31.6%, 6/19) significantly decreased in thyroid cancer patients. The IgG-positive rate (81.0%, 64/79) was satisfactory within 3 months of the last-dose vaccination. Ten (10.2%) patients had side effects after SARS-CoV-2 vaccination. Among them, two (2.0%) patients had a fever, five (5.1%) patients had injection site pain, one (1.0%) patient felt dizzy, and one patient felt dizzy and had injection site pain at the same time. Conclusion: SARS-CoV-2 vaccines (CoronaVac, BBIBP-CorV, and ZF2001) are safe in thyroid cancer patients. The regression time of SARS-CoV-2 IgG is significantly shorter in thyroid cancer patients than in healthy adults. Therefore, a booster vaccination dose may be earlier than the systematic strategy for thyroid cancer patients.

Durability of Humoral and Cellular Immunity after an Extended Primary Series with Heterologous Inactivated SARS-CoV-2 Prime-Boost and ChAdOx1 nCoV-19 in Dialysis Patients (ICON3).

The durability of a three-dose extended primary series of COVID-9 vaccine in dialysis patients remains unknown. Here, we assessed dynamic changes in SARS-CoV-2-specific humoral and cell-mediated immunity at baseline, 3 months, and 6 months after the extended primary series in 29 hemodialyzed (HD), 28 peritoneal dialyzed (PD) patients, and 14 healthy controls. Participants received two doses of inactivated SARS-CoV-2 vaccine followed by a dose of ChAdOx1 nCoV-19 vaccine. At 6 months, median anti-RBD IgG titers (IQR) significantly declined from baseline in the HD (1741 (1136-3083) BAU/mL vs. 373 (188-607) BAU/mL) and PD (1093 (617-1911) BAU/mL vs. 180 (126-320) BAU/mL) groups, as did the mean percent inhibition of neutralizing antibodies (HD: 96% vs. 81%; PD: 95% vs. 73%) (all p < 0.01). Age and post-vaccination serological response intensity were predictors of early humoral seroprotection loss. In contrast, cell-mediated immunity remained unchanged. In conclusion, humoral immunity declined substantially in dialysis patients, while cell-mediated immunity remained stable 6 months after the extended heterologous primary series of two inactivated SARS-CoV-2/ChAdOx1 nCoV-19 vaccine. A booster dose could be considered in dialysis patients 3 months after this unique regimen, particularly in the elderly or those with a modest initial humoral response.

Safety and protective capability of an inactivated SARS-CoV-2 vaccine on pregnancy, lactation and the growth of offspring in hACE2 mice.

The mass inoculation of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine to induce herd immunity is one of the most effective measures to fight COVID-19. The vaccination of pregnant women cannot only avoid or reduce the probability of infectious diseases, but also offers the most effective and direct protection for neonates by means of passive immunization. However, there is no randomized clinical data to ascertain whether the inactivated vaccination of pregnant women or women of childbearing age can affect conception and the fetus. We found that human angiotensin-converting enzyme 2 (hACE2) mice that were vaccinated with two doses of CoronaVac (an inactivated SARS-CoV-2 vaccine) before and during pregnancy exhibited normal weight changes and reproductive performance indices; the physical development of their offspring was also normal. Following intranasal inoculation with SARS-CoV-2, pregnant mice in the immunization group all survived; reproductive performance indices and the physical development of offspring were all normal. In contrast, mice in the non-immunization group all died before delivery. Analyses showed that inoculation of CoronaVac was safe and did not exert any significant effects on pregnancy, lactation, or the growth of offspring in hACE2 mice. Vaccination effectively protected the pregnant mice against SARS-CoV-2 infection and had no adverse effects on the growth and development of the offspring, thus suggesting that inoculation with an inactivated SARS-CoV-2 vaccine may be an effective strategy to prevent infection in pregnant women.

Comparison of the Clinical and Laboratory Findings and Outcomes of Hospitalized COVID-19 Patients Who Were Either Fully Vaccinated with Coronavac or Not: An Analytical, Cross Sectional Study.

COVID-19 vaccines are highly protective against severe disease; however, vaccine breakthrough infections resulting in hospitalization may still occur in a small percentage of vaccinated individuals. We investigated whether the clinical and microbiological features and outcomes were different between hospitalized COVID-19 patients who were either fully vaccinated with Coronovac or not. All hospitalized COVID-19 patients who had at least one dose of Coronavac were included in the study. The oldest unvaccinated patients with comorbidities, who were hospitalized during the same period, were chosen as controls. All epidemiologic, clinical and laboratory data of the patients were recorded and compared between the fully vaccinated and unvaccinated individuals. There were 69 and 217 patients who had been either fully vaccinated with Coronavac or not, respectively. All breakthrough infections occurred in the first 3 months of vaccination. Fully vaccinated patients were older and had more comorbidities than unvaccinated patients. There were minor differences between the groups in symptoms, physical and laboratory findings, anti-spike IgG positivity rate and level, the severity of COVID-19, complications, and clinical improvement rate. The mortality rate of fully vaccinated patients was higher than the mortality rate in unvaccinated patients in univariate analysis, which was attributed to the fact that vaccinated patients were older and had more comorbidities. The severity and clinical outcomes of hospitalized patients with breakthrough COVID-19 after Coronavac vaccination were similar to those of unvaccinated patients. Our findings suggest that the immune response elicited by Coronovac could be insufficient to prevent COVID-19-related severe disease and death within 3 months of vaccination among elderly people with comorbidities.

IMMUNOGENICITY AND SAFETY OF INACTIVATED SARS--COV--2 VACCINE ((VERO CELL)),, BBIBP--CORV ((SINOPHARM));;AN OBSERVATIONAL STUDY FROM PAKISTAN

Objective: To ascertain the immunogenicity and short-term safety of inactivated SARS-CoV-2 Vaccine (Vero Cell), BBIBP-CorV (Sinopharm) in our setup. Study Design: Cross-sectional study. Place and Duration of Study: Combined Military Hospital Sialkot Pakistan, from Feb to Apr 2021. Methodology: A total of 227 health care workers (HCWs) between 18 to 59 years of age were included in the study. Two doses of Inactivated SARS-CoV-2 Vaccine (Vero Cell), BBIBP-CorV were administered to all individuals 21 days apart and they were monitored for any vaccine-related adverse reactions for 7 days after each dose. Neutralizing antibodies (NAbs) in study subjects were detected in three samples i.e. before 1st dose of vaccine, 21 days after 1st dose and 14 days after 2nd dose by Elecsys Anti- SARS-CoV-2 S (Roche Diagnostics). Results: Mean age of individuals in the study was 36.70 ± 18.08 years and most individuals were in the 31-45 years age group. Fatigue and drowsiness were the most common adverse effects experienced by study subjects after 1st and 2nd dose of the vaccine followed by malaise and headache. Only 42 (39%) individuals developed positive neutralizing antibody titers in a sample taken 21 days after 1st dose while all individuals except one (99%) developed positive neutralizing antibody titers in a sample taken 2 weeks after 2nd vaccine dose. Conclusion: Inactivated SARS-CoV-2 Vaccine (Vero Cell), BBIBP-CorV is safe and well-tolerated with very few adverse reactions. Immunogenicity was well achieved as the seroconversion rate was 99% two weeks after 2nd dose of the vaccine. © 2021, Army Medical College. All rights reserved.

A Cohort Study on the Immunogenicity and Safety of the Inactivated SARS-CoV-2 Vaccine (BBIBP-CorV) in Patients With Breast Cancer; Does Trastuzumab Interfere With the Outcome?

Aim: To determine the efficacy and safety of inactivated SARS-CoV-2 vaccine (BBIBP-CorV) in patients with breast cancer. Methods: In this multi- institutional cohort study, a total of 160 breast cancer patients (mean age of 50.01 ± 11.5 years old) were assessed for the SARS-CoV-2 Anti-Spike IgG and SARS-CoV2 Anti RBD IgG by ELISA after two doses of 0.5 mL inactivated, COVID-19 vaccine (BBIBP-CorV). All patients were followed up for three months for clinical COVID-19 infection based on either PCR results or imaging findings. Common Terminology Criteria for Adverse Events were used to assess the side effects. Results: The presence of SARS-CoV-2 anti-spike IgG, SARS-CoV2 anti-RBD IgG, or either of these antibodies was 85.7%, 87.4%, and 93.3%. The prevalence of COVID-19 infection after vaccination was 0.7%, 0% and 0% for the first, second and third months of the follow-up period. The most common local and systemic side-effects were injection site pain and fever which were presented in 22.3% and 24.3% of patients, respectively. Discussion: The inactivated SARS-CoV-2 vaccine (BBIBP-CorV) is a tolerable and effective method to prevent COVID-19.

Absence of active systemic anaphylaxis in guinea pigs upon intramuscular injection of inactivated SARS-CoV-2 vaccine (Vero cells).

Background: The safety of novel vaccines against COVID-19 is currently a major focus of preclinical research. As a part of the safety evaluation testing package, 24 healthy guinea pigs were used to determine whether repeated administration of inactivated SARS-CoV-2 vaccine could induce active systemic anaphylaxis (ASA), and to evaluate its degree of severity.Method: According to sex and body weight, the animals were randomly divided into three experimental groups (eight animals per group). The negative control group received 0.9% sodium chloride (priming dose: 0.5 mL/animal; challenge dose: 1 mL/animal); the positive control group received 10% ovalbumin (priming dose: 0.5 mL/animal; challenge dose: 1 mL/animal); and the inactivated SARS-CoV-2 vaccine group received inactivated SARS-CoV-2 vaccines (priming dose: 100 U in 0.5 mL/animal; challenge dose: 200 U in 1 mL/animal). Priming dose administration was conducted by multi-point injection into the muscles of the hind limbs, three times, once every other day. On days 14 and 21 after the final priming injection, a challenge test was conducted. Half of the animals in each group were injected intravenously with twice the dose and volume of the tested substance used for immunization. During the experimental course, the injection site, general clinical symptoms, body weight, and systemic allergic reaction symptoms were monitored.Result: After intramuscular injection of inactivated SARS-CoV-2 vaccine, there were no abnormal reactions at the injection site, clinical symptoms, or deaths. There was no difference in body weight between the groups, and there were no allergic reactions. Conclusion: Thus, inactivated SARS-CoV-2 vaccine injected intramuscularly in guinea pigs did not produce ASA and had a good safety profile, which can provide actual data on vaccine risks and important reference data for clinical research on this vaccine.