scholarly journals Interpreting estimates of coronavirus disease 2019 (COVID-19) vaccine efficacy and effectiveness to inform simulation studies of vaccine impact: a systematic review

2021 ◽  
Vol 6 ◽  
pp. 185
Author(s):  
Natsuko Imai ◽  
Alexandra B. Hogan ◽  
Lucy Williams ◽  
Anne Cori ◽  
Tara D. Mangal ◽  
...  

Background: The multiple efficacious vaccines authorised for emergency use worldwide represent the first preventative intervention against coronavirus disease 2019 (COVID-19) that does not rely on social distancing measures. The speed at which data are emerging and the heterogeneities in study design, target populations, and implementation make it challenging to interpret and assess the likely impact of vaccine campaigns on local epidemics. We reviewed available vaccine efficacy and effectiveness studies to generate working estimates that can be used to parameterise simulation studies of vaccine impact. Methods: We searched MEDLINE, the World Health Organization’s Institutional Repository for Information Sharing, medRxiv, and vaccine manufacturer websites for studies that evaluated the emerging data on COVID-19 vaccine efficacy and effectiveness. Studies providing an estimate of the efficacy or effectiveness of a COVID-19 vaccine using disaggregated data against SARS-CoV-2 infection, symptomatic disease, severe disease, death, or transmission were included. We extracted information on study population, variants of concern (VOC), vaccine platform, dose schedule, study endpoints, and measures of impact. We applied an evidence synthesis approach to capture a range of plausible and consistent parameters for vaccine efficacy and effectiveness that can be used to inform and explore a variety of vaccination strategies as the COVID-19 pandemic evolves. Results: Of the 602 articles and reports identified, 53 were included in the analysis. The availability of vaccine efficacy and effectiveness estimates varied by vaccine and were limited for VOCs. Estimates for non-primary endpoints such as effectiveness against infection and onward transmission were sparse. Synthesised estimates were relatively consistent for the same vaccine platform for wild-type, but was more variable for VOCs. Conclusions: Assessment of efficacy and effectiveness of COVID-19 vaccines is complex. Simulation studies must acknowledge and capture the uncertainty in vaccine effectiveness to robustly explore and inform vaccination policies and policy around the lifting of non-pharmaceutical interventions.

Vaccines ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 510
Author(s):  
Lauren Périères ◽  
Fabienne Marcellin ◽  
Gora Lo ◽  
Camelia Protopopescu ◽  
El Ba ◽  
...  

Detailed knowledge about hepatitis B virus (HBV) vaccination coverage and timeliness for sub-Saharan Africa is scarce. We used data from a community-based cross-sectional survey conducted in 2018–2019 in the area of Niakhar, Senegal, to estimate coverage, timeliness, and factors associated with non-adherence to the World Health Organisation-recommended vaccination schedules in children born in 2016 (year of the birth dose (BD) introduction in Senegal) and 2017–2018. Vaccination status was assessed from vaccination cards, surveillance data, and healthcare post vaccination records. Among 241 children with available data, for 2016 and 2017–2018, respectively, 31.0% and 66.8% received the BD within 24 h of birth (BD schedule), and 24.3% and 53.7% received the BD plus at least two pentavalent vaccine doses within the recommended timeframes (three-dose schedule). In logistic regression models, home birth, dry season birth, and birth in 2016 were all associated with non-adherence to the recommended BD and three-dose schedules. Living over three kilometres from the nearest healthcare post, being the firstborn, and living in an agriculturally poorer household were only associated with non-adherence to the three-dose schedule. The substantial proportion of children not vaccinated according to recommended schedules highlights the importance of considering vaccination timeliness when evaluating vaccination programme effectiveness. Outreach vaccination activities and incentives to bring children born at home to healthcare facilities within 24 h of birth, must be strengthened to improve timely HBV vaccination.


2021 ◽  
Author(s):  
Emily Stephenson ◽  
◽  
Gary Reynolds ◽  
Rachel A. Botting ◽  
Fernando J. Calero-Nieto ◽  
...  

AbstractAnalysis of human blood immune cells provides insights into the coordinated response to viral infections such as severe acute respiratory syndrome coronavirus 2, which causes coronavirus disease 2019 (COVID-19). We performed single-cell transcriptome, surface proteome and T and B lymphocyte antigen receptor analyses of over 780,000 peripheral blood mononuclear cells from a cross-sectional cohort of 130 patients with varying severities of COVID-19. We identified expansion of nonclassical monocytes expressing complement transcripts (CD16+C1QA/B/C+) that sequester platelets and were predicted to replenish the alveolar macrophage pool in COVID-19. Early, uncommitted CD34+ hematopoietic stem/progenitor cells were primed toward megakaryopoiesis, accompanied by expanded megakaryocyte-committed progenitors and increased platelet activation. Clonally expanded CD8+ T cells and an increased ratio of CD8+ effector T cells to effector memory T cells characterized severe disease, while circulating follicular helper T cells accompanied mild disease. We observed a relative loss of IgA2 in symptomatic disease despite an overall expansion of plasmablasts and plasma cells. Our study highlights the coordinated immune response that contributes to COVID-19 pathogenesis and reveals discrete cellular components that can be targeted for therapy.


Vaccines ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 500
Author(s):  
Marco Trabucco Aurilio ◽  
Francesco Saverio Mennini ◽  
Simone Gazzillo ◽  
Laura Massini ◽  
Matteo Bolcato ◽  
...  

Background: While the COVID-19 pandemic has spread globally, health systems are overwhelmed by both direct and indirect mortality from other treatable conditions. COVID-19 vaccination was crucial to preventing and eliminating the disease, so vaccine development for COVID-19 was fast-tracked worldwide. Despite the fact that vaccination is commonly recognized as the most effective approach, according to the World Health Organization (WHO), vaccine hesitancy is a global health issue. Methods: We conducted a cross-sectional online survey of nurses in four different regions in Italy between 20 and 28 December 2020 to obtain data on the acceptance of the upcoming COVID-19 vaccination in order to plan specific interventions to increase the rate of vaccine coverage. Results: A total of 531 out of the 5000 nurses invited completed the online questionnaire. Most of the nurses enrolled in the study (73.4%) were female. Among the nurses, 91.5% intended to accept vaccination, whereas 2.3% were opposed and 6.2% were undecided. Female sex and confidence in vaccine efficacy represent the main predictors of vaccine intention among the study population using a logistic regression model, while other factors including vaccine safety concerns (side effects) were non-significant. Conclusions: Despite the availability of a safe and effective vaccine, intention to be vaccinated was suboptimal among nurses in our sample. We also found a significant number of people undecided as to whether to accept the vaccine. Contrary to expectations, concerns about the safety of the vaccine were not found to affect the acceptance rate; nurses’ perception of vaccine efficacy and female sex were the main influencing factors on attitudes toward vaccination in our sample. Since the success of the COVID-19 immunization plan depends on the uptake rate, these findings are of great interest for public health policies. Interventions aimed at increasing employee awareness of vaccination efficacy should be promoted among nurses in order to increase the number of vaccinated people.


2020 ◽  
pp. 147332502097329
Author(s):  
Hamed Mortazavi

As the number of patients infected with the 2019 novel coronavirus disease (nCOVID-19) increases, the number of deaths has also been increasing. According to World Health Organization (WHO), as of 4 October 2020, 34,804,348 cases had tested positive for nCOVID-19 globally, which among them, 1,030,738 confirmed deaths had occurred, equivalent to a case-fatality rate of 2.96%. However, in comparison with global statistics, the incidence and mortality of the nCOVID-19 infection are higher in Iran. As reported by the National Committee on COVID-19 Epidemiology of Ministry of Health of Iran, the total number of patients with confirmed COVID-19 infection has reached 468,119, of which 26,746 have died, equivalent to a case-fatality rate of 5.71%. Currently, there is solid evidence that older adults are at a higher risk of severe disease following infection from COVID-19.


2014 ◽  
Vol 58 (6) ◽  
pp. 656-660 ◽  
Author(s):  
Pedro Marques ◽  
Manuela Mafra ◽  
Carlos Calado ◽  
Anabela Martins ◽  
Joaquim Monteiro ◽  
...  

The uncommon aggressive pituitary tumors are named carcinomas when metastases are detected, either in the central nervous system and/or systemically. Some cases are associated with hormonal overproduction, but most are diagnosed because of local symptoms. These neoplasias are generally refractory to current treatments. A 51 year-old woman presented sudden onset of headache, left arm paresis and left facial hypoesthesia. Computed tomography scan and magnetic resonance imaging revealed a pituitary tumor invading the left sphenoidal and cavernous sinuses. Laboratory data excluded hormonal hypersecretion. The patient underwent transsphenoidal surgery and histological findings showed a neoplasia with Ki-67 estimated at 75%. Medical imaging excluded both a primary occult tumor and central nervous system or systemic dissemination. Three weeks postoperatively, neurological condition worsened, with new onset of ataxia, bilateral ptosis, ophthalmoplegia and an increase in the size of the lesion, leading to surgical intervention by craniotomy, followed by only a few sessions of radiotherapy, because of severe disease progression. Patient died nearly 2 months after the initial manifestations. This case illustrates the aggressiveness of some pituitary lesions, the limited efficacy of current treatment modalities such as surgery or radiotherapy and the pitfalls of the current pituitary tumors classification. To our knowledge, this case corresponds to one of the most aggressive pituitary neoplasms reported so far, with a very high Ki-67 index (75%) and short survival (2 months). Ki-67 index could be of prognostic value in pituitary tumors. Pituitary tumors World Health Organization (WHO) classification could be revisited.


2021 ◽  
Author(s):  
Ishak San ◽  
Emin Gemcioglu ◽  
Salih Baser ◽  
Nuray Yilmaz Cakmak ◽  
Abdulsamet Erden ◽  
...  

Abstract IntroductionIn this study, we compare the predictive value of clinical scoring systems that are already in use in patients with COVID-19, including the BCRSS, qSOFA, SOFA, MuLBSTA and HScore, for determining the severity of the disease. Our aim in this study is to determine which scoring system is most useful in determining disease severity and to guide clinicians.Materials and MethodsWe classified the patients into two groups according to the stage of the disease (severe and non-severe) by using the slightly modified and adopted interim guidance of the World Health Organization. Severe cases were divided into a group of surviving patients and a deceased group according to the prognosis. According to admission values, the BCRSS, qSOFA, SOFA, MuLBSTA, and HScore were evaluated at admission using the worst parameters available in the first 24 hours.ResultsOf the 417 patients included in our study, 46 (11%) were in the severe group, while 371 (89%) were in the non-severe group. Of these 417 patients, 230 (55.2%) were men. The median (IQR) age of all patients was 44 (25) years. In multivariate logistic regression analyses, BRCSS in the highest tertile (HR: 6.1, 95% CI: 2.105–17.674, p = 0.001) was determined as an independent predictor of severe disease in cases of COVID-19. In multivariate analyses, qSOFA was also found to be an independent predictor of severe COVID-19 (HR: 4.757, 95% CI: 1.438–15.730, p = 0.011). The area under the curve (AUC) of the BRCSS, qSOFA, SOFA, MuLBSTA, and HScore was 0.977, 0.961, 0.958, 0.860, and 0.698, respectively.ConclusionCalculation of the BRCSS and qSOFA at the time of hospital admission can predict critical clinical outcomes in patients with COVID-19, and their predictive value is superior to that of HScore, MuLBSTA, and SOFA. With early identification of the high-risk group using BRCSS and qSOFA, early interventions for high-risk patients can improve clinical outcomes in COVID-19.


Author(s):  
Judith Ju Ming Wong ◽  
Qalab Abbas ◽  
Soo Lin Chuah ◽  
Ririe Fachrina Malisie ◽  
Kah Min Pon ◽  
...  

There is a scarcity of data regarding coronavirus disease 2019 (COVID-19) infection in children from southeast and south Asia. This study aims to identify risk factors for severe COVID-19 disease among children in the region. This is an observational study of children with COVID-19 infection in hospitals contributing data to the Pediatric Acute and Critical Care COVID-19 Registry of Asia. Laboratory-confirmed COVID-19 cases were included in this registry. The primary outcome was severity of COVID-19 infection as defined by the World Health Organization (WHO) (mild, moderate, severe, or critical). Epidemiology, clinical and laboratory features, and outcomes of children with COVID-19 are described. Univariate and multivariable logistic regression models were used to identify risk factors for severe/critical disease. A total of 260 COVID-19 cases from eight hospitals across seven countries (China, Japan, Singapore, Malaysia, Indonesia, India, and Pakistan) were included. The common clinical manifestations were similar across countries: fever (64%), cough (39%), and coryza (23%). Approximately 40% of children were asymptomatic, and overall mortality was 2.3%, with all deaths reported from India and Pakistan. Using the multivariable model, the infant age group, presence of comorbidities, and cough on presentation were associated with severe/critical COVID-19. This epidemiological study of pediatric COVID-19 infection demonstrated similar clinical presentations of COVID-19 in children across Asia. Risk factors for severe disease in children were age younger than 12 months, presence of comorbidities, and cough at presentation. Further studies are needed to determine whether differences in mortality are the result of genetic factors, cultural practices, or environmental exposures.


Author(s):  
Monia Makhoul ◽  
Houssein H. Ayoub ◽  
Hiam Chemaitelly ◽  
Shaheen Seedat ◽  
Ghina R Mumtaz ◽  
...  

AbstractBackgroundSeveral SARS-CoV-2 vaccine candidates are currently in the pipeline. This study aims to inform SARS-CoV-2 vaccine development, licensure, decision-making, and implementation by determining key preferred vaccine product characteristics and associated population-level impact.MethodsVaccination impact was assessed at various efficacies using an age-structured mathematical model describing SARS-CoV-2 transmission and disease progression, with application for China.ResultsA prophylactic vaccine with efficacy against acquisition (VES) of ≥70% is needed to eliminate this infection. A vaccine with VES <70% will still have a major impact, and may control the infection if it reduces infectiousness or infection duration among those vaccinated who acquire the infection, or alternatively if supplemented with a moderate social-distancing intervention (<20% reduction in contact rate), or complemented with herd immunity. Vaccination is cost-effective. For a vaccine with VES of 50%, number of vaccinations needed to avert one infection is only 2.4, one severe disease case is 25.5, one critical disease case is 33.2, and one death is 65.1. Gains in effectiveness are achieved by initially prioritizing those ≥60 years. Probability of a major outbreak is virtually zero with a vaccine with VES ≥70%, regardless of number of virus introductions. Yet, an increase in social contact rate among those vaccinated (behavior compensation) can undermine vaccine impact.ConclusionsEven a partially-efficacious vaccine can offer a fundamental solution to control SARS-CoV-2 infection and at high cost-effectiveness. In addition to the primary endpoint on infection acquisition, developers should assess natural history and disease progression outcomes and/or proxy biomarkers, since such secondary endpoints may prove critical in licensure, decision-making, and vaccine impact.


2021 ◽  
Vol 39 (28_suppl) ◽  
pp. 148-148
Author(s):  
Stacey A. Ingram ◽  
Nicole E. Caston ◽  
Courtney J. Andrews ◽  
Rebecca England ◽  
Courtney Williams ◽  
...  

148 Background: The World Health Organization cited vaccine hesitancy as one of 2019’s top ten threats to global health, a threat that has been further exacerbated by COVID-19 pandemic. Existing COVID-19 vaccine hesitancy research focuses on the general population, but less is known about the specific concerns of medically vulnerable populations, including individuals with cancer. Methods: This cross-sectional analysis used data that assessed likelihood of COVID-19 vaccination (likely vs unlikely/unsure) among past or current patients with cancer from a nationwide survey administered in December 2020 by the Patient Advocate Foundation (PAF), a non-profit organization that provides case management and financial aid to patients diagnosed with a chronic illness. Inclusion criteria included previous or current cancer treatment, aged ≥ 19, and a valid e-mail address. Age, sex, race/ethnicity, and urban/rural residence were abstracted from the PAF database. Respondents self-reported education level, employment status, trust in media regarding COVID-19 pandemic, and media viewership on COVID-19 vaccine development. The Group-Based Medical Mistrust Scale assessed respondents’ level of mistrust in medical providers based on ethnicity. Likelihood of COVID-19 vaccine acceptance was evaluated using risk ratios (RR) and 95% confidence intervals (CI) from modified Poisson regression models with robust error variance. All variables were included in our model. Results: Of 429 respondents, 48% were unlikely/unsure about accepting the COVID-19 vaccine, primarily due to concerns about vaccine safety (32%) and worry about health conditions (12%). When compared to those likely to accept COVID-19 vaccine, respondents who were unlikely/unsure were more often Black, Indigenous, or People of Color (40% vs. 23%), aged 36-55 (40% vs. 29%), and female (80% vs. 65%). In adjusted analysis, Black respondents were 55% less likely to accept a COVID-19 vaccine, when compared to White respondents (RR 0.55; 95% CI 0.4-0.8). When compared to those who did not follow the media regarding COVID-19 vaccine development, those who followed the media very closely were 4.5 times more likely to accept a COVID-19 vaccine (RR 4.5; 95% CI 1.6-13.2). Respondents who reported below average trust in the media were 60% less likely to accept a COVID-19 vaccine (RR 0.6; 95% CI 0.5-0.8), compared to those who reported above average trust in the media. Conclusions: Despite being at high risk of COVID-19 morbidity and mortality, a substantial proportion of under-resourced individuals with cancer were unlikely/unsure about vaccination, exposing a significant disconnect between risk of severe disease and vaccine acceptance. Our analysis also reveals a need to assess for and debunk misinformation to increase vaccine enthusiasm among medically vulnerable populations.


Vaccines ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 668 ◽  
Author(s):  
Monia Makhoul ◽  
Houssein H. Ayoub ◽  
Hiam Chemaitelly ◽  
Shaheen Seedat ◽  
Ghina R. Mumtaz ◽  
...  

This study aims to inform SARS-CoV-2 vaccine development/licensure/decision-making/implementation, using mathematical modeling, by determining key preferred vaccine product characteristics and associated population-level impacts of a vaccine eliciting long-term protection. A prophylactic vaccine with efficacy against acquisition (VES) ≥70% can eliminate the infection. A vaccine with VES <70% may still control the infection if it reduces infectiousness or infection duration among those vaccinated who acquire the infection, if it is supplemented with <20% reduction in contact rate, or if it is complemented with herd-immunity. At VES of 50%, the number of vaccinated persons needed to avert one infection is 2.4, and the number is 25.5 to avert one severe disease case, 33.2 to avert one critical disease case, and 65.1 to avert one death. The probability of a major outbreak is zero at VES ≥70% regardless of the number of virus introductions. However, an increase in social contact rate among those vaccinated (behavior compensation) can undermine vaccine impact. In addition to the reduction in infection acquisition, developers should assess the natural history and disease progression outcomes when evaluating vaccine impact.


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