Immunogenicity of COVID-19 vaccines in chronic liver disease patients and liver transplant recipients: A systematic review and meta-analysis.

BACKGROUND AND AIMS: Chronic liver disease (CLD) patients and liver transplant (LT) recipients have an increased risk of morbidity and mortality from coronavirus disease 2019 (COVID-19). The immunogenicity of COVID-19 vaccines in CLD patients and LT recipients is poorly understood. The present study aimed to evaluate the immunogenicity of COVID-19 vaccines in CLD patients and LT recipients. METHODS: We searched electronic databases for eligible studies. Two reviewers independently conducted the literature search, extracted the data and assessed the risk of bias of included studies. The rates of detectable immune response were pooled from single-arm studies. For comparative studies, we compared the rates of detectable immune response between patients and healthy controls. The meta-analysis was conducted using the Stata software with a random-effects model. RESULTS: In total, 19 observational studies involving 4191 participants met the inclusion criteria. The pooled rates of detectable humoral immune response after two doses of COVID-19 vaccination in CLD patients and LT recipients were 95% (95% confidence interval [CI] = 88%-99%) and 66% (95% CI = 57%-74%) respectively. After two doses of vaccination, the humoral immune response rate was similar in CLD patients and healthy controls (risk ratio [RR] = 0.96; 95% CI = 0.90-1.02; p = .14). In contrast, LT recipients had a lower humoral immune response rate after two doses of vaccination than healthy controls (RR = 0.68; 95% CI = 0.59-0.77; p < .01). CONCLUSIONS: Our meta-analysis demonstrated that COVID-19 vaccination induced strong humoral immune responses in CLD patients but poor humoral immune responses in LT recipients.

Digital teaching and learning of surgical skills (not only) during the pandemic: a report on a blended learning project.

Due to the COVID-19 pandemic, digital teaching approaches should be used wherever possible. In this article we report on our project for digital teaching and learning of surgical skills. The compulsory elective "Intensivkurs Chirurgische Techniken" for medical students starting with semester 5 was designed as a blended learning course. One week before the face-to-face class, the students receive the learning and teaching material online in a Moodle course. In the face-to-face class, live demos of procedures (e.g. performing skin and intestinal sutures) are presented by the teachers. The learners then perform the practical procedures and record themselves with the camera of an iPad. They publish their videos in the Moodle course via an Opencast plugin. The implementation of an annotation tool enables everyone in the Moodle course to add free-text comments to selected parts of the videos (video-assisted feedback and coaching). As a result of the pandemic, the face-to-face class is being moved to a digital learning environment. For this purpose, we are extending the existing system with a web conference tool (BigBlueButton).