Mononucleosis is a disease caused by the pathogen Epstein-Barr (EBV). Epstein-Barr is a member of the herpes virus family and one of the most common human viruses. The virus occurs worldwide, and most people become infected with EBV sometime during their lives. In the United States 95% of adults between 35 and 40 years of age have been infected.
We think that the probable mode of transmission of the Epstein-Barr virus is saliva. The virus is indeed found in the saliva as well as the respiratory secretions, however does not readily spread from one individual to another without close contact. In other words, if you are around someone who has mononucleosis and they cough, you will likely not contract the mono. Closer contact is needed for the spread of the virus.
Further understand how serious mononucleosis is consider some serious statistics. In 2005 they found that E.B.V affects 98% of the world’s population. Also about 1 in 2000 people die a year from Mono. About 1 in 20 children with mono also have strep throat at the same time. 50% of people that have mono will have a swollen spleen or some will have a enlarged liver.