Sentinel surveillance of influenza-like illnesses revealed an increase in the cases of influenza C virus in children and adults in Austria, 2022, compared to previous years, following one season (2020/21) wherein no Influenza C virus was detected. Whole genome sequencing revealed no obvious genetic basis for the increase. We propose that the reemergence is explained by waning immunity from lack of community exposure due to restrictions intended to limit SARS-CoV-2 spread in prior seasons, pending further investigation.