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We investigate adaptive strategies to robustly and optimally control the COVID-19 pandemic via social distancing measures based on the example of Germany. Our goal is to minimize the number of fatalities over the course of two years without inducing excessive social costs. We consider a tailored model of the German COVID-19 outbreak with different parameter sets to design and validate our approach. Our analysis reveals that an open-loop optimal control policy can significantly decrease the number of fatalities when compared to simpler policies under the assumption of exact model knowledge. In a more realistic scenario with uncertain data and model mismatch, a feedback strategy that updates the policy weekly using model predictive control (MPC) leads to a reliable performance, even when applied to a validation model with deviant parameters. On top of that, we propose a robust MPC-based feedback policy using interval arithmetic that adapts the social distancing measures cautiously and safely, thus leading to a minimum number of fatalities even if measurements are inaccurate and the infection rates cannot be precisely specified by social distancing. Our theoretical findings support various recent studies by showing that (1) adaptive feedback strategies are required to reliably contain the COVID-19 outbreak, (2) well-designed policies can significantly reduce the number of fatalities compared to simpler ones while keeping the amount of social distancing measures on the same level, and (3) imposing stronger social distancing measures early on is more effective and cheaper in the long run than opening up too soon and restoring stricter measures at a later time. [ABSTRACT FROM AUTHOR]

Background: Chronic granulomatous disease (CGD) patients are susceptible to recurrent opportunistic infections and to recurrent or chronic inflammations of presumably non-infectious origin. Both types of manifestations are often accompanied by granuloma formation. Both can remain unnoticed until they deteriorate considerably and can become life-threatening if not treated in time., Objective: To evaluate the effectiveness of regular follow-up visits in CGD patients., Methods: Findings of imaging (ultrasound, radiographs, computer-tomography, magnetic resonance imaging), lung function tests, histopathological and microbiological assessments of biopsies have been reviewed., Results: A total of 32 CGD patients have been evaluated within 15 years. Of these eight patients have been checked regularly for more than 5 years. Early detection prior to specific clinical signs and consecutive treatment of six lung manifestations and one liver manifestation such as interstitial pneumonia with formation of small granulomas, formation of large granulomas, fibrosis, Aspergillus infections, and abscesses could presumably prevent considerable aggravation in seemingly healthy or mildly symptomatic patients. In contrast, patients without surveillance who presented with severe symptoms (seven manifestations) often had irreversible organ damage or even died., Conclusions: Regular follow-up visits can help prevent or mitigate clinical manifestations, improve life quality and expectancy and weigh indication for bone marrow transplantation in CGD patients.