The “tripledemic” is a term that some public health leaders and the news media are using to describe the current spread of three respiratory illnesses: COVID-19, flu (influenza), and RSV (respiratory syncytial virus).

During the fall and winter months, COVID-19, influenza (flu), and respiratory syncytial virus (RSV) cases and hospitalizations spike in many parts of the country. Each virus can pose a serious health threat, especially for young children, older people, people with weakened immune systems, and people with underlying health conditions.

Most cases of COVID-19, flu, and RSV are mild, with millions of people getting moderately sick, but the number of people who are becoming severely ill is rising. The spread of these illnesses, alongside COVID-19, strains our health system and limits the capacity and resources of healthcare facilities.

“Tripledemic” does not have a scientific definition, like “epidemic” or “pandemic.” It is an informal term used to convey the significance of the current spread of COVID-19, flu, and RSV.

Updated December 15, 2023