Infectious mononucleosis, or mono, refers to a group of symptoms usually caused by the Epstein-Barr virus (EBV). It typically occurs in teenagers, but you can get it at any age. The virus is spread through saliva, which is why some people call it “the kissing disease.”
People with mono often have a high fever, swollen lymph glands, and a sore throat. Most cases of mono are mild and resolve easily with minimal treatment. The infection is typically not serious and usually goes away on its own in one to two months.