Mononucleosis, also known as “mono,” is usually caused by a germ called the Epstein-Barr virus. Other viruses such as CMV and HIV, and other infections such as toxoplasmosis, may also cause a mononucleosis illness. Though best known for causing swollen glands and fatigue, mononucleosis can take many forms. Most children with mono recover without any problems. But the illness can take a long time to go away. In some cases, mono can cause problems with the liver, spleen, or heart. So it is important that mono be diagnosed and the child watched carefully.

Causes of mononucleosis

Mono can be easily transmitted from an infected person's saliva by:

  • Drinking and eating after them
  • Sharing a straw, cup, toothbrushes, and eating utensils
  • Kissing and close contact
  • Handling toys with children drool

Symptoms of mononucleosis

In children, common symptoms include:

  • Tiredness, weakness
  • Fever
  • Sore throat
  • Tender or swollen lymph nodes in the neck or armpits
  • Swollen tonsils
  • Rash
  • Sore muscles or stiffness
  • Headache
  • Loss of appetite, nausea
  • Dull pain in the stomach area
  • Enlarged liver and spleen
  • Headaches
  • Puffy eyes
  • Sensitivity to light

Diagnosis of mononucleosis

Mononucleosis may be diagnosed by a simple blood test performed by your doctor.

Treating mononucleosis

Because it is a viral infection, antibiotics won’t cure mono. Your child's health care provider may prescribe medications to help ease your child's pain or discomfort. The best treatment for mono is rest. A child with mono should also drink lots of fluids. To help your child feel better and recover sooner:

  • Make sure the child gets plenty of rest.
  • Keep the child warm.
  • Feed the child plenty of fluids, such as water or apple juice.
  • Do not let anyone smoke around the child.
  • Make sure your child avoids contact sports, and heavy lifting for a month to prevent injury to the spleen. The spleen can become enlarged during this illness. Discuss with your child's health care provider when he or she can return to normal activities.
  • Treat the child’s fever, sore throat, or aching muscles with children’s acetaminophen or ibuprofen. Never give your child aspirin.

Symptoms usually last for a few weeks, but can sometimes last for 1 to 2 months or longer. Even after symptoms have gone away, your child may be tired or weak for some time.

Preventing the spread of mononucleosis

While you’re caring for a child with mono:

  • Wash your hands with warm water and soap often, especially before and after tending to your sick child.
  • Monitor your own health and that of other family members
  • Limit a sick child’s contact with other children.
  • Clean dishes and eating utensils used by a sick child separately in very hot, soapy water. Or run them through the dishwasher.

When to seek medical care

Call the health care provider right away if your otherwise healthy child:

  • Is an infant under 3 months old with a rectal temperature of 100.4°F (38°C) or higher
  • Is a child of any age who has a repeated temperature of 104°F (40°C) or higher
  • Has a fever that lasts more than 24-hours in a child under 2 years old, or for 3 days in a child 2 years or older
  • Has had a seizure caused by the fever
  • Experiences difficult or rapid breathing.
  • Cannot be soothed or shows signs of irritability or restlessness.
  • Seems unusually drowsy, listless, or unresponsive.
  • Has trouble eating, drinking, or swallowing.
  • Stops breathing, even for an instant.
  • Shows signs of severe chest, neck, or abdominal pain.