Can you get mono more than once?

More than one cause. Traditional mononucleosis describes a flu like illness with fever, swollen glands & the appearance of monocytes ( a white blood cell type) in the blood. About 90% of cases are caused by the eb virus, a member of the herpes virus family.Once experienced, immunity should be lifelong. Other agents like CMV virus, toxoplasma gondii, & adeno virus can cause a similar illness.