The COVID-19 pandemic is concurrently an "infodemic." As the world edges close to the fourth year of the pandemic, message fatigue appears to have become a strong theme in public sentiment about health communication surrounding COVID. In this talk, I will discuss research in progress that examines the extent of message fatigue among the vaccinated in the U.S., the demographic and epidemiological correlates of message fatigue, and the relationship between message fatigue and the uptake of COVID-19 vaccine boosters. Preliminary results suggest that message fatigue is a prevalent and consequential phenomenon among this population. Continued public health messaging about COVID and vaccination should take this into account.