Final answer:
Splenomegaly is a common symptom in Epstein-Barr virus (EBV) infection, often seen in the second or third week of infection, and can vary in prevalence among cases.
Step-by-step explanation:
Splenomegaly, or the enlargement of the spleen, is a common symptom associated with Epstein-Barr virus (EBV) infection, which can result in infectious mononucleosis. While the exact percentage of EBV infections that present with splenomegaly can vary, it is typically observed in a substantial portion of cases. During the second or third week of infection, abdominal pain may occur due to the spleen and liver enlargement. Understanding the prevalence of splenomegaly in EBV infections is important for healthcare providers to consider potential complications, such as the increased risk of spleen rupture in enlarged spleens, and to guide patient management and counseling on activity restrictions to mitigate this risk.