Commonly referred to as “mono,” mononucleosis is a viral infection. Specifically, it is the VEB (Epstein-Barr virus) that causes the condition. Saliva appears to be its preferred vehicle for person-to-person transmission—which is why it is also known as the "kissing disease."
While this infection is more commonly-seen in young adults and adolescents, it can also affect children.
In general, the mononucleosis infection in children is asymptomatic. Symptoms, such as severe fatigue, fever, and a sore throat, are more common in young adults and adolescents. This is called infectious mononucleosis.
In the next few lines, you will learn more about its symptoms, mode of transmission, diagnosis and more.
How is mono transmitted?
As indicated in the introduction, VEB is transmitted mainly through contact with saliva. Kissing or even sharing utensils, glasses, bottles, etc. are therefore known modes of transmission.
Here are more details about the incubation and infectious period:
A person is contagious as soon as they become infected. As a result, they can pass the mononucleosis virus to more than one person, even before developing symptoms. This incubation period varies from person to person, ranging from 3 to 6 weeks.
Mononucleosis is most contagious in the peak of the symptomatic phase. Since the symptoms sometimes become incapacitating, the infected person often self-isolates for a few days or even weeks. Allowing them to rest is not only suggested to optimize healing: it is also a good way to protect those around them (classmates, co-workers, sports teammates, etc.)
It is also interesting to know that mononucleosis can be transmitted even months after symptoms disappear.
What are the symptoms of infectious mononucleosis (mono)?
Infectious mononucleosis has more than one symptom, and they are usually very undesirable. As noted above, these sometimes leave the person no other choice than to stay at home to rest.
First, the person notices a sore throat, which tends to intensify in the days following its onset. The back of the throat can also get very red and swollen, and become the site of white spots or a yellowish, viscous liquid similar to pus.
This sore throat is often accompanied by a fever that doesn’t seem to improve within the “famous” 48 to 72 hours.
Also, the person experiences extreme fatigue, which is peculiar to infectious mononucleosis. Loss of appetite can also be observed.
Left subcostal pain (a sign that the spleen is swollen), swollen lymph nodes, a throbbing headache, and general discomfort are also common symptoms of infectious mononucleosis.
More rarely, itchy patches can appear on the body. And although rarer, complications should not be overlooked.
What complications does mono cause?
The most well-known complication of mono is a ruptured spleen, which is why it is recommended that people with this condition avoid contact sports. Very rarely, other complications can occur, such as:
- Nerve damage
- Behavioural disorders
- Encephalitis or meningitis
How is it diagnosed?
The Epstein-Barr virus causes a defensive reaction in the immune system. Therefore, the latter secretes an exclusive antibody to the VEB, easily detected by laboratory tests.
For this reason, a doctor who suspects an infectious mononucleosis in their patient usually orders a blood sample for screening.
The swabs also allow them to rule out other causes of infection, which may result in very similar symptoms, such as cytomegalovirus and streptococcal infection, for example.
How is it treated?
First, the doctor advises the patient that this infection is contagious and is transmitted through saliva. This is how an infected person can avoid transmitting it to a family member (especially children or adolescents).
In a second step, the doctor suggests (among other things) to:
- Rest, as long as the symptoms are present
- Drink a lot of water
- Get enough sleep
As soon as the symptoms subside, the person can gradually resume their activities.
How to prevent mononucleosis
To date, there is no cure for infectious mononucleosis, let alone a vaccine. However, prevention is essential for people with weakened immune systems.
Patients should be careful not to exchange kisses and any other form of activity that may involve coming into contact with the saliva of an infected person (symptomatic or during the year following infection).
When should you consult a doctor?
Even though infectious mononucleosis is a common infection—which a majority of us carry, it is still important to see a doctor if any signs appear.
Complications can thus be avoided and transmission to others can be prevented.