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2.
Nat Med ; 27(10): 1693-1695, 2021 10.
Artigo em Inglês | MEDLINE | ID: covidwho-1526092

RESUMO

To evaluate the effectiveness of the BNT162b2 messenger RNA vaccine in pregnant women, we conducted an observational cohort study of pregnant women aged 16 years or older, with no history of SARS-CoV-2, who were vaccinated between 20 December 2020 and 3 June 2021. A total of 10,861 vaccinated pregnant women were matched to 10,861 unvaccinated pregnant controls using demographic and clinical characteristics. Study outcomes included documented infection with SARS-CoV-2, symptomatic COVID-19, COVID-19-related hospitalization, severe illness and death. Estimated vaccine effectiveness from 7 through to 56 d after the second dose was 96% (95% confidence interval 89-100%) for any documented infection, 97% (91-100%) for infections with documented symptoms and 89% (43-100%) for COVID-19-related hospitalization. Only one event of severe illness was observed in the unvaccinated group and no deaths were observed in either group. In summary, the BNT162b2 mRNA vaccine was estimated to have high vaccine effectiveness in pregnant women, which is similar to the effectiveness estimated in the general population.


Assuntos
Vacinas contra COVID-19/efeitos adversos , COVID-19/prevenção & controle , Complicações Infecciosas na Gravidez/prevenção & controle , Adolescente , Adulto , COVID-19/epidemiologia , COVID-19/virologia , Vacinas contra COVID-19/administração & dosagem , Estudos de Coortes , Feminino , Humanos , Incidência , Gravidez , SARS-CoV-2/isolamento & purificação , Adulto Jovem
6.
Microbiol Spectr ; 9(2): e0135221, 2021 10 31.
Artigo em Inglês | MEDLINE | ID: covidwho-1526454

RESUMO

The emerging new lineages of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) have marked a new phase of coronavirus disease 2019 (COVID-19). Understanding the recognition mechanisms of potent neutralizing monoclonal antibodies (NAbs) against the spike protein is pivotal for developing new vaccines and antibody drugs. Here, we isolated several monoclonal antibodies (MAbs) against the SARS-CoV-2 spike protein receptor-binding domain (S-RBD) from the B cell receptor repertoires of a SARS-CoV-2 convalescent. Among these MAbs, the antibody nCoV617 demonstrates the most potent neutralizing activity against authentic SARS-CoV-2 infection, as well as prophylactic and therapeutic efficacies against the human angiotensin-converting enzyme 2 (ACE2) transgenic mouse model in vivo. The crystal structure of S-RBD in complex with nCoV617 reveals that nCoV617 mainly binds to the back of the "ridge" of RBD and shares limited binding residues with ACE2. Under the background of the S-trimer model, it potentially binds to both "up" and "down" conformations of S-RBD. In vitro mutagenesis assays show that mutant residues found in the emerging new lineage B.1.1.7 of SARS-CoV-2 do not affect nCoV617 binding to the S-RBD. These results provide a new human-sourced neutralizing antibody against the S-RBD and assist vaccine development. IMPORTANCE COVID-19 is a respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The COVID-19 pandemic has posed a serious threat to global health and the economy, so it is necessary to find safe and effective antibody drugs and treatments. The receptor-binding domain (RBD) in the SARS-CoV-2 spike protein is responsible for binding to the angiotensin-converting enzyme 2 (ACE2) receptor. It contains a variety of dominant neutralizing epitopes and is an important antigen for the development of new coronavirus antibodies. The significance of our research lies in the determination of new epitopes, the discovery of antibodies against RBD, and the evaluation of the antibodies' neutralizing effect. The identified antibodies here may be drug candidates for the development of clinical interventions for SARS-CoV-2.


Assuntos
Anticorpos Neutralizantes/uso terapêutico , Anticorpos Antivirais/uso terapêutico , COVID-19/terapia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/metabolismo , Sítios de Ligação/imunologia , Vacinas contra COVID-19/imunologia , Cristalografia por Raios X , Modelos Animais de Doenças , Feminino , Humanos , Imunização Passiva/métodos , Imunoglobulina G/sangue , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Domínios e Motivos de Interação entre Proteínas/imunologia , Carga Viral/efeitos dos fármacos
7.
Expert Opin Ther Pat ; 31(12): 1177-1188, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: covidwho-1526144

RESUMO

Introduction: NGOs and governments of some countries have demanded suspension of patents protection of COVID-19 vaccines and the underlying technology to enhance worldwide access. At the same time, companies actually developing and producing COVID-19 vaccines have to navigate the patent landscape and have to deal with 3rd party patents.Areas covered: This article discusses these different aspects regarding patent protection of COVID-19 vaccines. Patent searches have been carried out in Espacenet and the ORBIT database. Different search strings were used by the author, based on his own background knowledge.Expert opinion: SARS-CoV 2 was for the first time fully described on 10 January 2020, so it is so far not possible to determine if, and by whom, patent applications were filed for respective vaccines. On that background, allegations that patents would be responsible for insufficient access to the vaccine in particular in developing countries are baseless. Even the key players are facing contraints caused by third-party patents, and legal disputes are already ongoing. Anyway, the bigger obstacle for worldwide equitable vaccine distribution seems to reside in know how transfer and production capacities, as ramping up production requires considerable efforts.


Assuntos
Vacinas contra COVID-19/uso terapêutico , COVID-19/prevenção & controle , Patentes como Assunto , Humanos , RNA Viral/imunologia
8.
N Engl J Med ; 385(16): 1535-1536, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: covidwho-1526124
10.
Nat Med ; 27(10): 1744-1751, 2021 10.
Artigo em Inglês | MEDLINE | ID: covidwho-1526090

RESUMO

CoronaVac, an inactivated SARS-CoV-2 vaccine, has been approved for emergency use in several countries. However, its immunogenicity in immunocompromised individuals has not been well established. We initiated a prospective phase 4 controlled trial (no. NCT04754698, CoronavRheum) in 910 adults with autoimmune rheumatic diseases (ARD) and 182 age- and sex-frequency-matched healthy adults (control group, CG), who received two doses of CoronaVac. The primary outcomes were reduction of ≥15% in both anti-SARS-CoV-2 IgG seroconversion (SC) and neutralizing antibody (NAb) positivity 6 weeks (day 69 (D69)) after the second dose in the ARD group compared with that in the CG. Secondary outcomes were IgG SC and NAb positivity at D28, IgG titers and neutralizing activity at D28 and D69 and vaccine safety. Prespecified endpoints were met, with lower anti-SARS-Cov-2 IgG SC (70.4 versus 95.5%, P < 0.001) and NAb positivity (56.3 versus 79.3%, P < 0.001) at D69 in the ARD group than in the CG. Moreover, IgG titers (12.1 versus 29.7, P < 0.001) and median neutralization activity (58.7 versus 64.5%, P = 0.013) were also lower at D69 in patients with ARD. At D28, patients with ARD presented with lower IgG frequency (18.7 versus 34.6%, P < 0.001) and NAb positivity (20.6 versus 36.3%, P < 0.001) than that of the CG. There were no moderate/severe adverse events. These data support the use of CoronaVac in patients with ARD, suggesting reduced but acceptable short-term immunogenicity. The trial is still ongoing to evaluate the long-term effectiveness/immunogenicity.


Assuntos
Anticorpos Antivirais/biossíntese , Doenças Autoimunes/complicações , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Doenças Reumáticas/complicações , Adulto , Anticorpos Neutralizantes/biossíntese , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/complicações , COVID-19/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Prev Med ; 153: 106860, 2021 12.
Artigo em Inglês | MEDLINE | ID: covidwho-1525994

RESUMO

Despite demonstrated efficacy of vaccines against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the causative agent of coronavirus disease-2019 (COVID-19), widespread hesitancy to vaccination persists. Improved knowledge regarding frequency, severity, and duration of vaccine-associated symptoms may help reduce hesitancy. In this prospective observational study, we studied 1032 healthcare workers who received both doses of the Pfizer-BioNTech SARS-CoV-2 mRNA vaccine and completed post-vaccine symptom surveys both after dose 1 and after dose 2. We defined appreciable post-vaccine symptoms as those of at least moderate severity and lasting at least 2 days. We found that symptoms were more frequent following the second vaccine dose than the first (74% vs. 60%, P < 0.001), with >80% of all symptoms resolving within 2 days. The most common symptom was injection site pain, followed by fatigue and malaise. Overall, 20% of participants experienced appreciable symptoms after dose 1 and 30% after dose 2. In multivariable analyses, female sex was associated with greater odds of appreciable symptoms after both dose 1 (OR, 95% CI 1.73, 1.19-2.51) and dose 2 (1.76, 1.28-2.42). Prior COVID-19 was also associated with appreciable symptoms following dose 1, while younger age and history of hypertension were associated with appreciable symptoms after dose 2. We conclude that most post-vaccine symptoms are reportedly mild and last <2 days. Appreciable post-vaccine symptoms are associated with female sex, prior COVID-19, younger age, and hypertension. This information can aid clinicians in advising patients on the safety and expected symptomatology associated with vaccination.


Assuntos
COVID-19 , SARS-CoV-2 , Vacinas contra COVID-19 , Feminino , Humanos , RNA Mensageiro , Vacinação
13.
Vaccine ; 39(47): 6876-6882, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: covidwho-1525977

RESUMO

OBJECTIVE: Vaccine shortage and supply-chain challenges have caused limited access by many resource-limited countries during the COVID-19 pandemic. One of the primary decisions for a vaccine-ordering decision-maker is how to allocate the limited resources between different types of vaccines effectively. We studied the tradeoff between efficacy and reach of the two vaccine types that become available at different times. METHODS: We extended a Susceptible-Infected-Recovered-Deceased (SIR-D) model with vaccination, ran extensive simulations with different settings, and compared the level of infection attack rate (IAR) under different reach ratios between two vaccine types under different resource allocation decisions. RESULTS: We found that when there were limited resources, allocating resources to a vaccine with high efficacy that became available earlier than a vaccine with lower efficacy did not always lead to a lower IAR, particularly if the former could vaccinate less than 42.5% of the population (with the selected study parameters) who could have received the latter. Sensitivity analyses showed that this result stayed robust under different study parameters. CONCLUSIONS: Our results showed that a vaccine with lower resource requirements (wider reach) can significantly contribute to reducing IAR, even if it becomes available later in the pandemic, compared to a higher efficacy vaccine that becomes available earlier but requires more resources. Limited resource in vaccine distribution is significant challenge in many parts of the world that needs to be addressed to improve the global access to life-saving vaccines. Understanding the tradeoffs between efficacy and reach is critical for resource allocation decisions between different vaccine types for improving health outcomes.


Assuntos
COVID-19 , Vacinas , Vacinas contra COVID-19 , Humanos , Pandemias , Alocação de Recursos , SARS-CoV-2 , Vacinação
14.
Med Hypotheses ; 157: 110700, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: covidwho-1525881

RESUMO

A subset of COVID-19 patients is experiencing secondary immune thrombocytopenia, also called immune thrombocytopenic purpura (ITP) or secondary hemophagocytic lymphohistiocytosis (HLH). The pathogenesis of SARS-CoV-2 associated thrombocytopenia is unknown. Very rare cases of vaccine induced prothrombotic immune thrombocytopenia (VIPIT) are occurring associated with COVID-19 vaccines. COVID-19 VIPIT is associated with autoantibodies targeting platelet factor 4 (PF4) for COVID-19 adenovirus vaccines. Herein, four models for hemophagocytic histocytes contributions to the etiology of thrombocytopenia associated with SARS-CoV-2 are proposed. One of the models proposes potential involvement of hemophagocytic histocytes targeting platelets bound by autoantibodies consistent with observed PF4 autoantibodies in COVID-19 VIPIT.


Assuntos
COVID-19 , Trombocitopenia , Vacinas contra COVID-19 , Histiócitos , Humanos , SARS-CoV-2 , Trombocitopenia/complicações
17.
Aging Clin Exp Res ; 33(11): 3151-3160, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: covidwho-1525638

RESUMO

BACKGROUND: The BNT162b2 SARS-CoV-2 mRNA vaccination has mitigated the burden of COVID-19 among residents of long-term care facilities considerably, despite being excluded from the vaccine trials. Data on reactogenicity (vaccine side effects) in this population are limited. AIMS: To assess reactogenicity among nursing home (NH) residents. To provide a plausible proxy for predicting vaccine response among this population. METHODS: We enrolled and sampled NH residents and community-dwelling healthcare workers who received the BNT162b2 mRNA vaccine, to assess local or systemic reactogenicity and antibody levels (immunogenicity). RESULTS: NH residents reported reactions at a much lower frequency and lesser severity than the community-dwelling healthcare workers. These reactions were mild and transient with all subjects experiencing more local than systemic reactions. Based on our reactogenicity and immunogenicity data, we developed a linear regression model predicting log-transformed anti-spike, anti-receptor-binding domain (RBD), and neutralizing titers, with a dichotomous variable indicating the presence or absence of reported reactions which revealed a statistically significant effect, with estimated shifts in log-transformed titers ranging from 0.32 to 0.37 (all p < 0.01) indicating greater immunogenicity in subjects with one or more reported reactions of varying severity. DISCUSSION: With a significantly lower incidence of post-vaccination reactions among NH residents as reported in this study, the BNT162b2 mRNA vaccine appears to be well-tolerated among this vulnerable population. If validated in larger populations, absence of reactogenicity could help guide clinicians in prioritizing vaccine boosters. CONCLUSIONS: Reactogenicity is significantly mild among nursing home residents and overall, subjects who reported post-vaccination reactions developed higher antibody titers.


Assuntos
COVID-19 , Vacinas , Vacinas contra COVID-19 , Pessoal de Saúde , Humanos , Casas de Saúde , RNA Mensageiro/genética , SARS-CoV-2
18.
MMWR Morb Mortal Wkly Rep ; 70(46): 1608-1612, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: covidwho-1524680

RESUMO

Population-based rates of infection with SARS-CoV-2 (the virus that causes COVID-19) and related health care utilization help determine estimates of COVID-19 vaccine effectiveness and averted illnesses, especially since the SARS-CoV-2 B.1.617.2 (Delta) variant began circulating in June 2021. Among members aged ≥12 years of a large integrated health care delivery system in Oregon and Washington, incidence of laboratory-confirmed SARS-CoV-2 infection, emergency department (ED) visits, and hospitalizations were calculated by COVID-19 vaccination status, vaccine product, age, race, and ethnicity. Infection after full vaccination was defined as a positive SARS-CoV-2 molecular test result ≥14 days after completion of an authorized COVID-19 vaccination series.* During the July-September 2021 surveillance period, SARS-CoV-2 infection occurred among 4,146 of 137,616 unvaccinated persons (30.1 per 1,000 persons) and 3,009 of 344,848 fully vaccinated persons (8.7 per 1,000). Incidence was higher among unvaccinated persons than among vaccinated persons across all demographic strata. Unvaccinated persons with SARS-CoV-2 infection were more than twice as likely to receive ED care (18.5%) or to be hospitalized (9.0%) than were vaccinated persons with COVID-19 (8.1% and 3.9%, respectively). The crude mortality rate was also higher among unvaccinated patients (0.43 per 1,000) than in fully vaccinated patients (0.06 per 1,000). These data support CDC recommendations for COVID-19 vaccination, including additional and booster doses, to protect individual persons and communities against COVID-19, including illness and hospitalization caused by the Delta variant (1).


Assuntos
COVID-19/epidemiologia , COVID-19/terapia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Adolescente , Adulto , Idoso , COVID-19/prevenção & controle , Vacinas contra COVID-19/administração & dosagem , Criança , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Oregon/epidemiologia , Vacinação/estatística & dados numéricos , Washington/epidemiologia , Adulto Jovem
19.
Front Cell Infect Microbiol ; 11: 690621, 2021.
Artigo em Inglês | MEDLINE | ID: covidwho-1523677

RESUMO

The coronavirus disease (COVID-19) is caused by a positive-stranded RNA virus called severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), belonging to the Coronaviridae family. This virus originated in Wuhan City, China, and became the cause of a multiwave pandemic that has killed 3.46 million people worldwide as of May 22, 2021. The havoc intensified with the emergence of SARS-CoV-2 variants (B.1.1.7; Alpha, B.1.351; Beta, P.1; Gamma, B.1.617; Delta, B.1.617.2; Delta-plus, B.1.525; Eta, and B.1.429; Epsilon etc.) due to mutations generated during replication. More variants may emerge to cause additional pandemic waves. The most promising approach for combating viruses and their emerging variants lies in prophylactic vaccines. Several vaccine candidates are being developed using various platforms, including nucleic acids, live attenuated virus, inactivated virus, viral vectors, and protein-based subunit vaccines. In this unprecedented time, 12 vaccines against SARS-CoV-2 have been phased in following WHO approval, 184 are in the preclinical stage, and 100 are in the clinical development process. Many of them are directed to elicit neutralizing antibodies against the viral spike protein (S) to inhibit viral entry through the ACE-2 receptor of host cells. Inactivated vaccines, to the contrary, provide a wide range of viral antigens for immune activation. Being an intracellular pathogen, the cytotoxic CD8+ T Cell (CTL) response remains crucial for all viruses, including SARS-CoV-2, and needs to be explored in detail. In this review, we try to describe and compare approved vaccines against SARS-CoV-2 that are currently being distributed either after phase III clinical trials or for emergency use. We discuss immune responses induced by various candidate vaccine formulations; their benefits, potential limitations, and effectiveness against variants; future challenges, such as antibody-dependent enhancement (ADE); and vaccine safety issues and their possible resolutions. Most of the current vaccines developed against SARS-CoV-2 are showing either promising or compromised efficacy against new variants. Multiple antigen-based vaccines (multivariant vaccines) should be developed on different platforms to tackle future variants. Alternatively, recombinant BCG, containing SARS-CoV-2 multiple antigens, as a live attenuated vaccine should be explored for long-term protection. Irrespective of their efficacy, all vaccines are efficient in providing protection from disease severity. We must insist on vaccine compliance for all age groups and work on vaccine hesitancy globally to achieve herd immunity and, eventually, to curb this pandemic.


Assuntos
COVID-19 , Pandemias , Vacinas contra COVID-19 , Humanos , Pandemias/prevenção & controle , SARS-CoV-2 , Vacinas de Produtos Inativados
20.
JMIR Public Health Surveill ; 7(11): e31707, 2021 11 09.
Artigo em Inglês | MEDLINE | ID: covidwho-1523636

RESUMO

BACKGROUND: The COVID-19 pandemic continues to have a disproportionate effect on ethnic minorities. Across countries, greater vaccine hesitancy has been observed among ethnic minorities. After excluding foreign domestic helpers, South Asians make up the largest proportion of ethnic minorities in Hong Kong. It is necessary to plan for COVID-19 vaccination promotional strategies that cater to the unique needs of South Asians in Hong Kong. OBJECTIVE: This study investigated the prevalence of COVID-19 vaccine uptake among a sample of South Asians in Hong Kong. We examined the effects of sociodemographic data and factors at individual level (perceptions), interpersonal level (information exposure on social media), and sociostructural level (cultural) based on the socioecological model. METHODS: A cross-sectional web-based survey was conducted on May 1-31, 2021. Participants were South Asian people aged 18 years or older living in Hong Kong; able to comprehend English, Hindi, Nepali, or Urdu; and having access to a smartphone. Three community-based organizations providing services to South Asians in Hong Kong facilitated the data collection. The staff of the community-based organizations posted the study information in WhatsApp groups involving South Asian clients and invited them to participate in a web-based survey. Logistic regression models were fit for data analysis. RESULTS: Among 245 participants, 81 (33.1%) had taken at least one dose of the COVID-19 vaccine (one dose, 62/245, 25.2%; and both doses, 19/245, 7.9%). After adjusting for significant background characteristics, cultural and religious reasons for COVID-19 vaccine hesitancy were associated with lower COVID-19 vaccine uptake (adjusted odds ratio [AOR] 0.83, 95% CI 0.71-0.97; P=.02). At the individual level, having more positive attitudes toward COVID-19 vaccination (AOR 1.31, 95% CI 1.10-1.55; P=.002), perceived support from significant others (AOR 1.29, 95% CI 1.03-1.60; P=.03), and perceived higher behavioral control to receive COVID-19 vaccination (AOR 2.63, 95% CI 1.65-4.19; P<.001) were associated with higher COVID-19 vaccine uptake, while a negative association was found between negative attitudes and the dependent variable (AOR 0.73, 95% CI 0.62-0.85; P<.001). Knowing more peers who had taken the COVID-19 vaccine was also associated with higher uptake (AOR 1.39, 95% CI 1.11-1.74; P=.01). At the interpersonal level, higher exposure to information about deaths and other serious conditions caused by COVID-19 vaccination was associated with lower uptake (AOR 0.54, 95% CI 0.33-0.86; P=.01). CONCLUSIONS: In this study, one-third (81/245) of our participants received at least one dose of the COVID-19 vaccine. Cultural or religious reasons, perceptions, information exposure on social media, and influence of peers were found to be the determinants of COVID-19 vaccine uptake among South Asians. Future programs should engage community groups, champions, and faith leaders, and develop culturally competent interventions.


Assuntos
COVID-19 , Vacinas , Grupo com Ancestrais do Continente Asiático , Vacinas contra COVID-19 , Estudos Transversais , Hong Kong , Humanos , Internet , Pandemias , SARS-CoV-2
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