Turning up the heat on COVID-19: heat as a therapeutic intervention
Marc Cohen, Elizabeth A Repasky, Jari Laukkanen
F1000Research, doi:10.12688/f1000research.23299.1
Enveloped viruses such as SAR-CoV-2 are sensitive to heat and are destroyed by temperatures tolerable to humans. All mammals use fever to deal with infections and heat has been used throughout human history in the form of hot springs, saunas, hammams, steamrooms, sweat-lodges, steam inhalations, hot mud and poultices to prevent and treat respiratory infections and enhance health and wellbeing. This paper reviews the evidence for using heat to treat and prevent viral infections and discusses potential cellular, physiological and psychological mechanisms of action. In the initial phase of infection, heat applied to the upper airways can support the immune system's first line of defence by supporting muco-ciliary clearance and inhibiting or deactivating virions where they first lodge. This may be further enhanced by the inhalation of steam containing essential oils with anti-viral, mucolytic and anxiolytic properties. Heat applied to the whole body can further support the immune system's second line of defence by mimicking fever and activating innate and acquired immune defences and building physiological resilience. Heat-based treatments also offer psychological benefits and enhanced mental wellness by focusing attention on positive action, enhancing relaxation and sleep, inducing 'forced-mindfulness', and invoking the power of positive thinking and 'remembered wellness'. Heat is a cheap, convenient and widely accessible therapeutic modality and while no clinical protocols exist for using heat to treat COVID-19, protocols that draw from traditional practices and consider contraindications, adverse effects and infection control measures could be developed and implemented rapidly and inexpensively on a wide scale. While there are significant challenges in implementing heat-based therapies during the current pandemic, these therapies present an opportunity to integrate natural medicine, conventional medicine and traditional wellness practices, and support the wellbeing of both patients and medical staff, while building community resilience and reducing the likelihood and impact of future pandemics.
Author Response 12 Jul 2020
Marc Cohen I agree that this is a timely and interesting topic that covers a wide range of literature and am grateful for your comments, which have led to improvements in the paper's content and flow. I have now modified the wording to better reflect the difference between fever and externally applied heat stress and have referenced a review of the different forms of heat treatment that are currently being used or are under investigation for cancer therapy and suggest they may be useful for treating COVID-19. I have also added more detail on the adverse effects of heat and have reorganised some sections to improve the flow of information and make the paper more cohesive. Competing Interests: All competing interests have been declared in the authorship statement.
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