Book excerpt: Viruses are smart, mutating, and becoming resistant to antiviral pharmaceuticals. Global crises such as COVID-19, SARS, and dengue feaver spread more quickly than we can develop medicines to fight them. Herbalist and best-selling author Stephen Harrod Buhner has studied the antiviral properties of plants for many years. In this comprehensive guide, he profiles the plants that have proven most effective in fighting viral infections and provides in-depth instructions for preparing and using formulations to address the most common infections and strengthen immunity, safely and naturally. The updated 2nd edition includes an expanded guide to COVID-19, including a review of the most up-to-date medical research and the plant medicines that have been found to be most potent in preventing infection, lessening the impact of the virus on the body, and addressing longer-term effects and co-infections.