关键词： COVID-19   Vaccine trial   Homologous booster   Heterologous booster   ChAdOx1 nCov-19   COVISHIELD   BBV152   Covaxin   Immunogenicity   Safety  

摘要： Background Primary SARS-CoV-2 vaccination has been shown to wane with time and provide lower protection from disease with new viral variants, prompting the WHO to recommend the administration of booster doses. We determined the safety and immunogenicity of homologous or heterologous boosters with ChAdOx1 nCoV-19 (COVISHIELDTM) or BBV152 (COVAXIN (R)), the two vaccines used widely for primary immunization in India, in participants who had already received two primary doses of these vaccines. Methods Participants primed with two doses each of COVISHIELDTM or COVAXIN (R) 12-36 weeks previously, were randomised to receive either COVISHIELDTM or COVAXIN (R) booster in a 1:1 ratio. The primary outcome was day 28 post-booster anti-spike IgG seropositivity and secondary outcomes were anti-spike IgG levels and assessment of safety and reactogenicity. The results of 90 days intention-to-treat analysis are presented. This trial is registered with ISRCTN (CTRI/2021/08/035648). Findings In the COVISHIELDTM primed group with 200 participants, the seropositivity 28 days post booster in the heterologous COVAXIN (R) arm was 99% and non-inferior to the homologous COVISHIELDTM arm, which was also 99% (difference 0%;95% CI: -2.8% to 2.7%). The geometric mean concentration (GMC) of anti-spike antibodies following heterologous COVAXIN (R) boost on day 28 was 36,190.78 AU/mL (95% CI: 30,526.64-42,905.88) while the GMC following homologous COVISHIELDTM boost was 97,445.09 AU/mL (82,626.97-114,920.7). In the COVAXIN (R) primed group with 204 participants, the seropositivity 28 days post booster in the heterologous COVISHIELDTM arm was 100% and non inferior to the homologous COVAXIN (R) arm which was 96% (difference 4%, 95% CI: 0.2%-7.8%). The GMC following heterologous COVISHIELDTM boost was 241,681.6 AU/mL (95% CI: 201,380.2-290,048.3) compared to homologous COVAXIN (R) boost, which was 48,473.94 AU/mL (95% CI: 38,529.56-60,984.95). The day 28 geometric mean ratio (GMR) of the anti-spike I

关键词： SARS-CoV-2   Vaccine   Microangiopathic hemolytic anemia   Thrombotic microangiopathy   AstraZeneca   AZD1222  

摘要： Vaccine-associated thrombotic thrombocytopenic purpura (TTP) is a rare type of acquired TTP recently reported after COVID-19 vaccination. Merely four cases are ascribed to the ChAdOx1 nCoV-19 vaccine in the medical literature till the preparation of this study. In this case report, we describe a 43-year-old man who developed symptoms of TTP four days after receiving the second dose of the ChAdOx1 nCoV-19 vaccine. Peripheral blood smear demonstrated multiple schistocytes. Given a high plasmic score, he received plasma exchange, corticosteroids, and rituximab, and later, low ADAMTS 13 activity and high-titer ADAMTS inhibition antibody confirmed the diagnosis of COVID-19 vaccine-associated TTP. COVID-19 vaccine-associated TTP is an infrequent consequence of SARS-CoV-2 vaccination but with a substantial mortality rate which must be considered as one of the crucial differential diagnoses of post-COVID-19 vaccine thrombocytopenia besides vaccine-induced immune thrombotic thrombocytopenia and Immune thrombocytopenic purpura.

关键词： SARS-CoV-2   COVID-19   CoronaVac   nCoV-19   antibodies  

摘要： Background: The pandemic unleashed by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected more than 500 million people worldwide and caused more than 6 million deaths. Cellular and humoral immunity induced by infection or immunization are key factors in controlling the viral burden and avoiding the recurrence of coronavirus disease. The duration and effectiveness of immunity after infection is relevant to pandemic policy interventions, including the timing of vaccine boosters. Objectives: We sought to evaluate longitudinal binding and functional antibodies against SARS-CoV-2 receptor-binding domain in police officers and health care workers with a history of coronavirus disease 2019 and compare with SARS-CoV-2-naive individuals after vaccination with adenovirus-based ChAdOx1 nCoV-19 (AstraZeneca-Fiocruz) or the inactivated CoronaVac vaccine (Sinovac-Butantan Institute). Methods: A total of 208 participants were vaccinated. Of these, 126 (60.57%) received the ChAdOx1 nCoV-19 vaccine and 82 (39.42%) received the CoronaVac vaccine. Prevaccination and postvaccination blood was collected, and the amount of anti-SARS-CoV-2 IgG and the neutralizing ability of the antibodies to block the interaction between angiotensin-converting enzyme 2 and receptor-binding domain were determined. Results: Subjects with preexisting SARS-CoV-2 immunity and who received a single dose of ChAdOx1 nCoV-19 or CoronaVac have similar or superior antibody levels when compared with levels in seronegative individuals even after 2 doses of the vaccine. Neutralizing antibody titers of seropositive individuals were higher with a single dose of either ChAdOx1 nCoV-19 or CoronaVac compared with those of seronegative individuals. After 2 doses, both groups reached a plateau response. Conclusions: Our data reinforce the importance of vaccine boosters to increase specific binding and neutralizing SARSCoV-2 antibodies. (J Allergy Clin Immunol Global

关键词： ACE2 receptor   Binding affinity  

摘要： ContextSince the outbreak of COVID-19 in 2019, the 2019-nCovcoronavirus has appeared diverse mutational characteristics due to its ownflexible conformation. One multiple-mutant strain (Omicron) with surprisinglyinfective activity outburst, and affected the biological activities of currentdrugs and vaccines, making the epidemic significantly difficult to prevent andcontrol, and seriously threaten health around the world. Importunatelyexploration of mutant characteristics for novel coronavirus Omicron can supplystrong theoretical guidance for learning binding mechanism of mutant ***'s more, full acknowledgement of key mutated-residues on Omicron strain canprovide new methodology of the novel pathogenic mechanism to human ACE2receptor, as well as the subsequent vaccine *** this research, 3D structures of 32 single-point mutationsof 2019-nCov were firstly constructed, and 32-sites multiple-mutant Omicronwere finally obtained based one the wild-type virus by homology modeling *** total number of 33 2019-nCov/ACE2 complex systems were acquired byprotein-protein docking, and optimized by using preliminary molecular dynamicsimulations. Binding free energies between each 2019-nCov mutation system andhuman ACE2 receptor were calculated, and corresponding binding patternsespecially the regions adjacent to mutation site were analyzed. The resultsindicated that one total number of 6 mutated sites on the Omicron strain playedcrucial role in improving binding capacities from 2019-nCov to ACE2 ***, we performed long-term molecular dynamic simulations andprotein-protein binding energy analysis for the selected 6 mutations. 3infected individuals, the mutants T478K, Q493R and G496S with lower bindingenergies -66.36, -67.98 and -67.09 kcal/mol also presents the high *** findings indicated that the 3 mutations T478K, Q493R and G496S play thecrucial roles in enhancing binding affinity of Omicron to human ACE2 *** th

关键词： 新型冠状病毒   疫苗接种   特殊健康状况  

摘要： 特殊健康状况人群是新型冠状病毒感染的重症高危人群，国内外研究结果均表明接种新型冠状病毒疫苗（简称新冠疫苗）可以保护易感人群，降低重症率、死亡率和疾病负担。我国人口众多，其中特殊健康状况人群（感染性疾病，肿瘤，循环系统、呼吸系统、消化系统疾病，肾脏疾病，血液系统、风湿免疫系统疾病，内分泌疾病、神经系统疾病等人群）基数庞大，广泛接种新冠疫苗是保障高危人群的主要预防措施。为提高上海市和我国特殊健康状态成人新冠疫苗接种率，上海市CDC、上海市预防医学会免疫规划专委会组织成立特殊健康状况（成人）新型冠状病毒疫苗接种专家建议编写组，结合本学科诊疗经验，从疾病概述、现况与问题、疫苗接种原则这3个方面制订针对常见特殊健康状态成人的新冠疫苗接种专家建议。

关键词： 新型冠状病毒   奥密克戎变异株   上海市   核酸检测   转阴时间  

摘要： 目的比较不同临床特征对新型冠状病毒(SARS-CoV-2)奥密克戎(Omicron)变异株感染后核酸检测转阴时间的影响,为新型冠状病毒肺炎的隔离治疗提供科学依据。方法收集2022年4月27日—2022年6月8日上海市杨浦区五角场定点医院收治的228例上海市确诊SARS-CoV-2奥密克戎变异株感染的轻症患者流行病学和临床资料,以核酸转阴时间为结局变量,以核酸转阴时间(≤18 d)120例为A组和(>18 d)108例为B组。利用单因素及多因素logistic回归分析影响核酸转阴时间的因素。结果228例患者的平均核酸转阴时间为(18.7±12.1)d,中位时间18 d。其中A组平均核酸转阴时间为(13.2±2.0)d,B组为(20.8±1.3)d。单因素分析发现,高血压、冠心病、糖尿病、低钾血症、恶性肿瘤疾病对核酸转阴时间的影响差异无统计学意义(P>0.05);而合并有脑血管病、白细胞减少症、呼吸系统慢性疾病及疫苗接种对核酸转阴时间的影响差异有统计学意义(P<0.05)。进一步通过多因素Logistic回归分析发现,合并慢性呼吸系统疾病、未接种疫苗对核酸转阴时间延长有显著影响(P<0.05)。结论是否合并高血压、冠心病、糖尿病、低钾血症、恶性肿瘤、神经精神疾病、慢性消化系统疾病对核酸转阴时间无显著影响,而合并有慢性呼吸系统疾病以及未接种新冠疫苗与“奥密克戎”感染患者核酸转阴时间的延长显著相关。

关键词： 冠状病毒感染   冠状病毒   心功能不全  

摘要： 新型冠状病毒(severe acute respiratory syndrome coronavirus 2,SARS-CoV-2)属β冠状病毒,是目前已知的第7种可以感染人的冠状病毒,其引发的SARS-CoV-2感染(corona virus disease 2019,COVID-19)疫情在全世界范围内大流行已逾3年[1,2]。