What is it?

Infectious mononucleosis - also called "mono" or "the kissing disease" - is an acute infection of the lymphatic system caused by the Epstein-Barr Virus (EBV). It is usually characterized by fatigue, fever, sore throat, and swollen glands in the neck. However, some mild cases are largely asymptomatic.

Who gets "mono"?

Almost everyone, at any age, can get infectious mononucleosis. In the United States, mono is a common problem of the late teen and young adult years, with 70-80% of all documented cases occurring in people ages 15-30 years. In less developed countries, people typically get the infection at earlier ages and in milder forms.

How is it spread

The usual way of contracting mono is thought to be through contact with infected saliva on eating and drinking utensils and in kissing.

Once in the body the virus multiplies in the lymphocytes (white blood cells that form a part of the immune system).

It is thought that persons previously infected may serve as a source of virus that spreads to others. Because tracing of person to person spread is so difficult, just how long a person may be a source of infection is unknown. Communicability appears to last from some time before symptoms appear until at least the sore throat and fever disappear, and possibly longer.

The amount of time between viral exposure and the appearance of symptoms varies from 4 to 7 weeks. Roommates and household members are at only slightly increased risk of being infected.

What are the symptoms?

Early on, vague complaints of "not feeling well," headache, tiredness, puffy eyelids, and decreased appetite are common. Later, fever, sore throat, and swollen lymph glands at the side and back of the neck, and also under the arm and in the groin may appear. The firm, tender glands vary from bean to egg size for several days to a few weeks. A fever for about five days is usual, and may continue intermittently for one to three weeks. Tonsillitis, trouble swallowing and bleeding gums may be present. Some people may develop a rash.

[Mono in children and some adults is often unrecognized due to the mild nature of the symptoms.]

In half of all cases, the spleen, an organ under the left rib cage, will be enlarged. Liver enlargement, under the right rib, occurs about 20 percent of the time. Rarely, yellowing of the skin (jaundice) is seen. In most people, infection with EBV confers life long immunity.

Important Caution!!!!!

Strenuous exercise, any lifting or straining, and all competitive and contact sports should be completely avoided until recovery from mono is complete. Damage to and rupture of the spleen resulting in emergency surgery and/or death has occurred in persons with mono. Patients should receive a doctor's clearance before resuming exercise, work involving physical exertion, and athletic competition. Patients whose mononucleosis is accompanied by jaundice should avoid alcohol. Rarely are there cases of death from airway obstruction, heart inflammation, or central nervous system involvement.

How is mono diagnosed?

Mono causes an increase in and some differentiation of white blood cells called lymphocytes and produces heterophile antibodies in the blood. A blood test will show more white blood cells than normal and some atypical ones. The heterophile antibodies will produce "clumping" when the infected blood is mixed with red blood cells from horses. This is called a slide agglutination "spot test" or "monospot test" or "mono test."

Sometimes the appearance of blood changes are delayed so that repeat tests may be necessary to support the diagnosis. Usually, the antibodies are present in sufficient numbers by as early as day four, but sometimes not until day 21 of the illness. Some 20% of mono sufferers may never test positive on this agglutination test and may require more involved and expensive testing to rule out other, possibly more serious conditions. In the absence of positive tests, mononucleosis may be diagnosed on symptoms alone.

How is mono treated?

Since mono is caused by a virus, it is not susceptible to antibiotic therapy. Rest, lots of fluids and a well-balanced diet are recommended. Drug treatment is targeted to specific symptoms and individual experiences. Ibuprofen is given for relief of headache, muscle pains, chills and fever. Warm, salt water gargles are recommended for sore throat. Corticosteroids are sometimes used if symptoms are severe enough to cause breathing difficulties. Sometimes bacterial infections such as strep or sinus infection can be present along with mono. If this is the case antibiotics can be helpful in treating the bacterial infection. Ampicillin or amoxicillin should not be used as it often causes an allergic - like rash in those with mononucleosis.

Acute symptoms of mono may last 7-10 days, and fatigue for 4-6 weeks. One should anticipate some limitations to normal activities during this time.

What is chronic fatigue syndrome?

Symptoms of this chronic debilitating state are persistent or recurrent fatigue, frequent respiratory infections, sore throats, low grade fevers, swollen glands, headaches and depression. While the Ebstein-Barr virus has been suggested as one of the causes of chronic fatigue syndrome, this has not been proven.

Is there any prevention for mono?

Using hygienic measures including hand washing to prevent the spread of the virus is important. Maintaining optimum health through balanced exercise, rest, diet and getting prompt medical attention for symptoms are further ways to avoid mononucleosis and its complications.