In­fec­ti­o­us mo­no­nuc­le­o­sis ("kis­sing di­se­a­se")

Infectious mononucleosis
Infectious mononucleosis

Infectious mononucleosis is often called “kissing disease”: It can be transmitted by kissing because the virus is shed in saliva. But it may also be passed to other people by coughing, sneezing, or by sharing a glass or plate with someone who has the disease. However, mono is less contagious than a common cold. The infection often occurs during childhood or adolescence. Younger children normally only have a few symptoms, and the condition often goes unrecognized. In a teenager or young adult, the symptoms may be more severe. It’s important to be careful of complications, e.g. an enlarged spleen.

Symptoms of mononucleosis

For the first three days, the patient might suffer from symptoms similar to a cold or flu, such as:

  • Malaise
  • Fatigue
  • Sometimes loss of appetite
  • Sometimes chills

Afterwards more intense symptoms appear, including:

  • Often persistent slight temperature (38 to 39°C)
  • Severe throat pain
  • Headache
  • Enlarged lymph nodes in neck, armpits and groin area
  • Reddened throat
  • Swollen tonsils
  • Skin rash that can be itchy
  • Swollen spleen

The virus has an incubation period of around four to six weeks (in young kids it might be shorter). Fever and throat pain normally lessen within a couple of weeks, but fatigue, swollen lymph nodes and enlarged spleen often last longer.

Causes and origin of mononucleosis

The Epstein-Barr virus causes mononucleosis. In general, this virus isn’t very dangerous. Worldwide, around 95 percent of all adults up to 30 years of age have been exposed to the Epstein-Barr virus, and have built up antibodies. That means that these people normally won't get kissing disease again. But the virus might be reactivated – without displaying any symptoms.

Consequences of mononucleosis

Complications of the kissing disease might be more serious than the condition itself. Mono may lead to enlargement of the spleen. In the worst case, the organ might rupture causing sharp pain in the left side of the upper abdomen. The affected person needs medical care immediately, and probably even surgery.

Other complications could include liver problems, e.g. hepatitis and jaundice, and at times, anemia, heart problems, swollen tonsils (which can result in breathing problems) as well as thrombocytopenia, meningitis, encephalitis, etc.
However, in people with a weakened immune system and in patients who must take drugs to suppress immunity after an organ transplant, the Epstein-Barr virus may lead to a much more serious condition.  

Regarding medicaments, there might be a risk of rash with some medications, such as Amoxicillin and other penicillin derivatives. A few people with mono who take one of these drugs might develop a rash. They should rather use other antibiotics that treat infections that sometimes accompany kissing disease.

Prevention and therapy of mononucleosis

There is no special therapy for mono. The best treatment for the condition is staying in bed and drinking plenty of fluids. Antibiotics don't work against viral infections such as kissing disease. If the patient develops a strep infection, sinus infection or an infection of the tonsils, he/she might need treatment with antibiotics for these accompanying bacterial infections. To ease severe swelling of the throat and tonsils, the physician probably prescribes a corticosteroid medication, e.g. prednisone.

Preventive measures

There is no vaccine to prevent mononucleosis. Patients should avoid kissing other people or sharing drinks or food with them at least until several days after the fever has gone. It’s even possible that the Epstein-Barr virus persists in the saliva for months after the mono infection.