Preparing for the 2019-2020 influenza season.

Although the 2017-2018 influenza season had very high rates of influenza-associated illness, the 2018-2019 influenza season was comparable to previous seasons. Influenza A was the most commonly identified type worldwide, although variations in influenza A subtype prevalence existed. Influenza vaccination remains the single most effective way to prevent influenza-associated illness. A novel influenza antiviral, baloxavir, has demonstrated promising results; however, concerns about development of resistance exist.