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Vaccination prevents severe morbidity and mortality from COVID-19 in the general population. The immunogenicity and efficacy of SARS-CoV-2 vaccines in patients with antibody deficiency is poorly understood.
ObjectivesCOVID-19 in patients with antibody deficiency (COV-AD) is a multi-site UK study that aims to determine the immune response to SARS-CoV-2 infection and vaccination in patients with primary or secondary antibody deficiency, a population that suffers from severe and recurrent infection and does not respond well to vaccination.
MethodsIndividuals on immunoglobulin replacement therapy or with an IgG less than 4 g/L receiving antibiotic prophylaxis were recruited from April 2021. Serological and cellular responses were determined using ELISA, live-virus neutralisation and interferon gamma release assays. SARS-CoV-2 infection and clearance were determined by PCR from serial nasopharyngeal swabs.
ResultsA total of 5.6% (n?=?320) of the cohort reported prior SARS-CoV-2 infection, but only 0.3% remained PCR positive on study entry. Seropositivity, following two doses of SARS-CoV-2 vaccination, was 54.8% (n?=?168) compared with 100% of healthy controls (n?=?205). The magnitude of the antibody response and its neutralising capacity were both significantly reduced compared to controls. Participants vaccinated with the Pfizer/BioNTech vaccine were more likely to be seropositive (65.7% vs. 48.0%, p?=?0.03) and have higher antibody levels compared with the AstraZeneca vaccine (IgGAM ratio 3.73 vs. 2.39, p?=?0.0003). T cell responses post vaccination was demonstrable in 46.2% of participants and were associated with better antibody responses but there was no difference between the two vaccines. Eleven vaccine-breakthrough infections have occurred to date, 10 of them in recipients of the AstraZeneca vaccine.
ConclusionSARS-CoV-2 vaccines demonstrate reduced immunogenicity in patients with antibody deficiency with evidence of vaccine breakthrough infection.
相似文献DICOM viewers must fulfill roles beyond primary diagnostic interpretation, including serving as presentation tools in teaching and multidisciplinary conferences, thereby enabling multiple individuals to review images collaboratively in real time. When in-person gathering is not possible, a variety of solutions have been deployed to maintain the ability for spatially separated users to view medical images simultaneously. These approaches differ in their backend architectures, utilization of application-specific optimizations, and ultimately in their end user satisfaction. In this work, we systematically compare the performance of conventional screensharing using a videoconferencing application with that of a custom, synchronized DICOM viewer linked using Web Real Time Communications (WebRTC) technology. We find superior performance for the WebRTC method with regard to image quality and latency across a range of simulated adverse network conditions, and we show how increasing the number of conference participants differentially affects the bandwidth requirements of the two viewing solutions. In addition, we compare these two approaches in a real-world teaching scenario and gather the feedback of trainee and faculty radiologists, who we found to favor the WebRTC method for its decreased latency, improved image quality, ease of setup, and overall experience. Ultimately, our results demonstrate the value of application-specific solutions for the remote synchronized viewing of medical imaging, which, given the recent increase in reliance on remote collaboration, may constitute a significant consideration for future enterprise viewer procurement decisions.
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