Infectious mononucleosis is a viral infectious disease caused by the Epstein-Barr virus. Symptoms of the infection include exhaustion, flu, sore throat, swollen lymph nodes, and a distinctive rash. Also called the "kissing disease" due to its spread via contact with a person's saliva. Most adolescents and young adults get sick, but anyone can get sick at any age. People need to know what the signs and symptoms of mono are and take care not ...