How common are secondary bacterial infections or sepsis with a mono infection?

Not quantified: Secondary bacterial infections are common enough to make most of the lists of complications of ebv that leads to infectious mononucleosis, but i could not find that a case rate had been published at this time (i.e. A percentage of cases that develop secondary infections). The illness does cause relative immune compromise through splenic inflammation and neutropenia in some cases.

Rare: But not unheard of. Group a strep is at the top.