Mono is caused by the Epstein-Barr virus (EBV). It is most often seen in adolescents and young adults. Children can get the virus, but it often goes unnoticed because their symptoms are mild. Older adults usually do not get mono, because they have immunity to the virus. This virus is most active in ages 13-18 

Mono can be spread through contact with saliva, mucus from the nose and throat, and sometimes tears. Because the virus can be spread through kissing, it has earned the nickname the "kissing disease." If you have mono, you can avoid passing the virus to others by not kissing anyone and by not sharing things like drinking glasses, eating utensils, or toothbrushes.
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