You can obtain mono at any age, although teenagers and adolescents develop this disease at a high frequency. Typically, the symptoms last several weeks, but in some can last months. It would vary depending on the patient.
For further testing to confirm the diagnosis you may want to obtain tests for antibodies specific to the Epstein-Barr virus.
Treatment is mainly supportive, but in your case, the symptoms are persisting. There are controversial data regarding treatment with steroids or antiviral medications (i.e. Acyclovir), that you may want to discuss with your personal physician, or be referred to an infectious disease specialist.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
Kevin, M.D.
Medical Weblog:
kevinmd_b