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Health library/Infectious Mononucleosis

Infections

Infectious Mononucleosis

Also known as: Glandular fever, Kissing disease, Mono, Mononucleosis

Infectious mononucleosis is usually caused by Epstein-Barr virus. Fatigue may last longer than the initial illness, and an enlarged spleen can be a concern.

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What you may notice

Symptoms can overlap with other conditions and vary between people.

  • Marked fatigue
  • Sore throat
  • Fever
  • Swollen neck glands

Understanding care

Clinical care may include assessment of infection, hydration and possible spleen or liver involvement. A qualified clinician decides which investigations and options fit the individual situation.

When to seek help

Seek review for persistent severe fatigue or throat symptoms. Sudden severe upper abdominal or shoulder pain, fainting or breathing difficulty requires emergency care.

For severe breathing difficulty, collapse, suspected stroke, or another emergency, call local emergency services immediately. In India, call 112.

Read the medical sources

These sources support the educational article and offer more detail.

Educational reading · Updated 6 October 2026

Prepared from the linked sources. This summary has not had an independent clinician review. A qualified clinician can assess symptoms and explain which information applies to you.

A child and a caring grown-up reading a picture book together

LITTLE PEOPLE. BIG FEELINGS.

It’s okay to have
a lot of questions.

A doctor visit or an unfamiliar health word can feel scary. You can ask a trusted grown-up to help you understand, one small question at a time.

01

Say how you feel.

“I feel worried” is a good place to start.

02

Ask for simple words.

“Can you explain that in a way I understand?”

03

Bring someone you trust.

A caring adult can help you ask and listen.

For children and their grown-ups. This illustration explains a conversation, not a diagnosis. An adult should seek qualified care for a child who is unwell.

Infectious Mononucleosis — First AID health library