Infectious mononucleosis (or mono) is a common contagious disease that may result insymptomsof profound fatigue or tiredness.
Mono may be the sole cause or a contributor of persistent fatigue.
Mononucleosis Causes
Mononucleosisis not a sleep disorder but it can cause fatigue that’s just as debilitating.

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This virus is spread by personal contact.
Mono can also be caused bycytomegalovirus (CMV).
In a minority of people, though, fatigue may still be present six months after the initial infection.

Get our printable guide for your next healthcare provider’s appointment to help you ask the right questions.
In those cases,further evaluationmay be necessary.
These common conditions often contribute to unrestful sleep.
Because they require differenttreatment, they shouldn’t be overlooked as having a possible role in ongoing symptoms.
Depending on your specific symptoms, your healthcare provider may also test you for anemia and thyroid dysfunction.
Depression and anxiety are also common causes of fatigue.
Get our printable guide for your next healthcare provider’s appointment to help you ask the right questions.
Because fatigue has numerous possible causes, the diagnostic process can be long and frustrating.
That’s worth the wait.
Australian Academy of Science.Kissing the Epstein-Barr virus goodbye?
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Centers for Disease Control and Prevention.What causes ME/CFS causes.