Okay, fine. Yes, those are diseases that are monitored. But explosive diarrhea is a symptom, not a disease. Sometimes people just get the runs for any number of reasons.

That's why saying there was an increase in "explosive diarrhea" sounds odd. Public health agencies generally monitor diseases that cause diarrhea, not the symptom itself in isolation.

It's like saying there was an increase in fevers during the height of COVID, or a spike in people feeling pain after breaking a bone. Those are symptoms of underlying conditions, not the thing that's actually being tracked.

Maybe I'm missing some context, but the wording still strikes me as strange.