Phytotherapeutic Evidence Against Coronaviruses and Prospects for COVID-19

The emergence of the novel β-coronavirus (SARS-CoV-2) and subsequent outbreak of COVID-19, is a global health challenge with no known treatment to date and has culminated in significant morbidity and mortality. This article highlights current understanding on SARSCoV- 2 based on the available scientific evidence on human coronavirus (HCoV) infections, which could offer novel insights and therapeutic targets for SARS-CoV-2, the causative agent of COVID-19. Specifically, the paper presents available phytotherapeutic evidence against pathogenic HCoVs with a view to identifying potent plant-derived antiviral agents that could be developed to aid the fight against coronaviruses and the current COVID-19. Evidently, elucidation of CoV integral proteins such as the spike protein, angiotensin-converting enzyme 2, 3C-like cysteine protease and papain-like protease, as good targets for drug developments has lent credence to the use of medicinal plants or their metabolites as prophylaxis or treatment interventions in CoV infections and holds promising ground for SARS-CoV-2. While some promising phytocompounds are currently under clinical trials for COVID-19, increased research into plants and in-depth characterization of their metabolites could reveal more interesting results that would benefit humanity in its fight against emerging and re-emerging viral infections including the current COVID-19. Overall, given the current body of evidence on the potential development of phytotherapeutics for COVID-19, fears need to be allayed while clinical trials continue. Conclusively, the lockdown and other preventive measures which have been implemented in most parts of the world should be humanely exercised and supported to ensure compliance and safety of lives.