Exploring the Efficacy of Traditional Herbs in Combating COVID-19: A Comprehensive Review

Abstract

The entire world witnessed the COVID-19 pandemic outbreak. It has become deadly everywhere across the globe. COVID-19 mortality varies across age groups and has been linked to an individual's innate immunity. In contrast, it was more lethal in immunocompromised people. The spread of viruses is slowed by both passive immunity and vaccine-aided acquired immunity. However, vaccine-induced immunity is transient, and there is no assurance that vaccinemediated antibodies will be effective against all future virus mutants. As a result, natural immunity boosters have become essential supplements that must be used nowadays to stay immunized against such infections. In Ayurvedic medicine, traditional Indian spices have been used for a long time to boost the immune system and fight off different diseases. This review aims to disseminate information about traditional natural medicine in repurposing as an immunity booster and for antiviral effects in COVID-19. Using published articles from recent years, the in silico docking study, survey-based study, and in vitro and preclinical research work on selected traditional herbs for their anti-inflammatory, immunomodulating, and antiviral properties are summarized. Withania somnifera, Piper nigrum, Emblica officinalis, Andrographis paniculate, Glycyrrhiza glabra, Ocimum sanctum, Piper longum, and Curcuma longa are some of the most commonly used natural spices studied extensively and hence selected in this review. This context summarizes selected plants showing immunomodulatory and antiviral effects in experimental animals, simulation, and clinical studies. By virtue of antiviral potential, the chosen herbs could be used for repurposing in COVID-19 management after thorough clinical investigations.