These include:

• Serious fatigue and a sore throat
• Swollen, painful lymph nodes which must be looked at by a doctor
• A skin rash on the face or body similar to measles
• A tenderness or pain in the upper-left of the abdomen which can indicates that your spleen may be enlarged

 The spleen is an important organ in the body and if enlarged, can rupture if you pursue contact sports or vigorous exercise. Medical intervention is necessary if you have any of the symptoms.