The rise of several significant variants of SARS-CoV-2, the virus that causes COVID-19, has attracted the attention of health and science experts worldwide. In an editorial published in JAMA: The Journal of the American Medical Association, experts from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, outline how these variants have arisen, concerns about whether vaccines currently authorized for use will continue to protect against new variants, and the need for a global approach to fighting SARS-CoV-2 as it spreads and acquires additional mutations.