Flu gets worse in the afternoon, PEM usually better
Flu & friends usually cause some symptoms PEM does not – like soare throat, running nose, coughing, fever, while typical PEM-symptoms might be less prominent.
For me, it just feels different. I’m just fighting my first severe flu-like infection since CFS started, and it feels completely different even when the words to describe it are almost the same.
On a more serious note:
ymmv.
Gute und rasche Besserung für alle!