Characterization of the Immune Reaction to Covid-19 Treatment with Dexamethasone: A Narrative Review

Purpose of Study: The spread of SARS-CoV-2 and the resulting Coronavirus Disease 2019 (COVID-19) continues to manifest in individuals in varying severity with limited treatment options available. Despite research efforts put forth in developing therapeutic options for treatment of COVID-19 disease, effective and well understood mechanisms remain limited. Corticosteroid treatment with dexamethasone was shown to be beneficial for those with severe illness early in the pandemic with little understanding of its beneficial mechanism. This narrative review describes the current findings regarding the mechanism of action of dexamethasone treatment in the setting of SARS-CoV-2 infection. Methods Used: A comprehensive search of Embase and PubMed was conducted in consultation with a health sciences librarian. Search terms included (1) COVID-19 (2) dexamethasone (3) animal model and (4) immune response. No limits were used on the search and other reviews were excluded. Search results were screened based on titles and s before being selected for full text review. Outcomes recorded included characterization of the microenvironment of lung tissue following SARS-CoV-2 through cytokine measurement, histopathological staining and analysis of lung tissue, and clinical outcomes such as survival time. Summary of Results: The search resulted in 100 articles. Of these, 8 articles were identified that met the inclusion criteria. Three conducted experiments with Syrian hamsters, two with mice, two with alveolar macrophages, and one study was conducted with human subjects. Dexamethasone treatment was found to diminish inflammatory cytokine levels and preserve the integrity of lung tissue in several animal models and in vitro experiments in the setting of SARS-CoV-2 infection. Dexamethasone treatment was also found to reduce inflammatory cell infiltration of lung tissue infected with SARS-CoV-2. In humans, combination therapy of low dose dexamethasone with spironolactone proved more effective at lowering inflammatory markers than high dose dexamethasone alone. Conclusion(s): Collectively, the articles included in this review support the use of dexamethasone treatment in SARS-CoV-2 infection. Protective effects exhibited with dexamethasone treatment suggest that its action may be linked to the inflammatory nature of COVID-19 disease. Macrophage regulation and diminished inflammatory cytokine levels were hypothesized as possible mechanistic features of dexamethasone action but lacked exact characterization. Further exploration of combination treatment with dexamethasone and its mechanism of action is needed to identify specific and effective therapeutic strategies in the future.

A back and forth between tourism and health: From medical tourism to global health

Health is an often-overlooked issue in the touristic development of territories. However, the recent pandemic linked to Covid-19, by bringing the tourism sector to a halt, has revealed the importance of health issues for this economic sector. This book deals with the interaction between tourism and health in all its facets and offers a complete overview of the subject, the beginnings of which date back to Antiquity. The arguments presented here are based on a back-and-forth approach between tourism studies and health sciences. Various themes are thus addressed, such as health risks, health issues for travellers linked to tourism practices, medical tourism, health mobility and the global processes that accompany it, as well as the impact of tourism development on public health in destinations. A Back and Forth Between Tourism and Health highlights the need to include the health dimension in tourism planning and invites a paradigm shift in thinking about the tourism sector. © ISTE Ltd 2022.