Both prolonged COVID and prolonged flu are health problems that not only require attention, but can affect vital health. While the consequences and causal effects of prolonged or post-COVID COVID syndrome have been known for a long time, the debilitating and prolonged symptoms of the flu can also be similar in some way.
For example, anecdotal evidence has revealed that both prolonged COVID and flu-like symptoms cause considerably similar symptoms, including anxiety, dyspnea, mental confusion, persistent cough or fever, fatigue, and muscle aches. However, the most persistent symptoms so far have been largely linked to a history of COVID infection.
Other than that, while there is some link to severity, researchers are still looking to find if there is an apparent link between the severity of flu infections and prolonged onset of symptoms.