The Kissing Disease

It’s highly contagious, inconvenient and can be painful, but generally mononucleosis is not a serious condition.

August means back to school, back to books, back to homework and back to sharing pencils and germs. Kids can’t wait to gather in hallways talking about things like the kissing disease and who has it and from whom he or she might have caught it. It makes for good gossip and speculation. It’s just their age. They can’t help themselves. It’s also that age, 10 to 19, in which the incidence of infectious mononucleosis, the medical term for “kissing disease,” is highest. Approximately six to eight youths per 1,000 per year are diagnosed with it.

Mono, most often clinically diagnosed by the classic triad of symptoms—enlarged lymph nodes, sore throat, fever—doesn’t necessarily indicate that a person has spent hours kissing a crush. Dr. Rhonda Colombo, infectious disease specialist with Georgia Health Sciences University’s Medical College of Georgia, says, “It’s one way to get mono, but anything that results in the exchange of oral secretions can infect a person.” Therefore, the viruses that cause mononucleosis can be transmitted from one person to another through frequent sharing of eating utensils, water bottles, drinking straws or other items that can carry quantities of saliva.

The viruses, however, do not live on surfaces. Contracting mono from public water fountains, cafeteria tables, school desks or casual social contact is extremely unlikely. “The virus is spread by intimate contact. You get it by swapping bodily fluids,” says Dr. Jack Austin, who specializes in internal medicine and infectious disease. 

Mononucleosis is typically caused by the Epstein-Barr Virus (EBV), one of the most common human viruses. Along with clinical diagnosis, the monospot test, a blood test for antibodies to EBV, can confirm infection. In what some people refer to as atypical mono, Cytomegalovirus (CMV) is the usual culprit. Atypical mono has the same symptoms as typical mono, but the person tests negative on the monospot test. Dr. Colombo explains that CMV causes more of a febrile illness than does EBV. Like EBV, however, CMV remains in the body for life and may reactivate in other periods, causing complications but not a repeat case of mono.

“Expression of symptoms is up to luck,” says Dr. Austin, who notes that for most people the signs of infection are so mild as to go unnoticed or to be marked up as a routine viral infection that runs its course. Dr. Colombo agrees, adding, “If you’ve never had mono as far as you know, there’s a good chance you have had it.” Mono symptoms, if they appear, occur after a four- to six-week incubation period, which is why it is extremely difficult to pinpoint the individual from whom the virus was caught. Interestingly, people can get mono twice—once by EBV and once by CMV. “The chance of you having severe mono twice is not great,” says Dr. Austin.

It is unclear why adolescents are more susceptible to mono than other age groups. It is an experimental stage of life during which adolescents spend extended time in large groups, increasing the possibility of coming into contact with a contagious individual. While EBV infection does occur in young children, perhaps due to the exchange of saliva via toys swapped from one child’s mouth to another’s, it is often asymptomatic. “There are a variety of theories that [increased incidence of mono in adolescence] has to do with the way the immune system develops,” says Dr. Colombo, who also explains that the expression of mono symptoms in adolescents tends to be a phenomenon of industrialization and upper socioeconomic class. In third-world countries and lower socioeconomic classes, younger children present with symptoms, perhaps due to crowded living conditions increasing the likelihood of significant exchange of saliva through shared vessels and utensils.

The explanation for why people over the age of 25 seldom contract mononucleosis is somewhat simpler. By the time they reach adulthood, the vast majority of people have already been infected with either EBV or CMV or both. It is estimated that 95 percent of all adults have been infected with EBV. Unfortunately, for that small percentage of adults who have not, if they become infected, the symptoms are often more severe than if they had contracted the illness earlier in life.

Symptomatic support is the only real treatment for infectious mononucleosis. Plenty of rest will help with associated fatigue. Over-the-counter, non-steroidal, anti-inflammatory medications help alleviate pain and swelling of lymph nodes and tonsils, plus relieve fever. (Do not give aspirin to a child with a fever, as it is linked to another illness known as Reye’s Syndrome.) Of course, maintaining proper hydration is also important. “Within a week or two,” says Dr. Austin, “most people are over it.”

Because infectious mononucleosis is viral and not bacterial, antibiotics are ineffective in treatment and the use of penicillin-type antibiotics in the absence of a secondary bacterial infection may cause a rash. Dr. Colombo assures, “The vast majority of cases of mono are self-limiting and will resolve on their own.” There are no antivirals for EBV and the antiviral for CMV, because of risks associated with it, is only approved for use in HIV patients.

Still there are circumstances in which a person who suspects he or she has mono should see a physician. Because strep throat, if untreated, poses the threat of serious complications, a strep test should be performed in the event of a persistent, severe sore throat. In addition, since mononucleosis can be accompanied by a swollen spleen, abdominal pain should be checked by a doctor immediately. Pain in the abdomen may indicate potential rupture of the spleen. Activities such as contact sports should not be resumed until splenic swelling has subsided. Finally, anyone who has difficulty breathing, maintaining proper hydration, controlling fever or who has other underlying health issues compromising the immune system should see his or her physician.

Infection with EBV may also result in mono-related hepatitis. “The word hepatitis means inflammation of the liver,” says Dr. Austin, who warns not to confuse mono-related hepatitis with hepatitis A, B or C. Mono-related hepatitis is almost always mild and short-lived. Rarely does it cause lasting liver damage and it cannot be passed from the infected individual to others in the way that hepatitis B and C are. Dr. Colombo notes, in keeping with increased severity of mono symptoms in people infected beyond adolescence, “Adults may be more at risk for enlarged liver or hepatitis.” Jaundice and abdominal pain in the presence of mono symptoms are the usual indicators of mono-related hepatitis.

Preventative measures against infectious mono include such things as avoiding intimate contact with a person recently infected and not sharing items that could transmit saliva from one person to another, such as toothbrushes, sports bottles and forks. Keep in mind that there are no risks from casual contact with a person who is infected, but also understand that during the incubation period, when no symptoms are present, a person is contagious and that “once someone becomes infected, they excrete the virus for months after becoming well,” says Dr. Austin. Many people who are infected never realize it and may inadvertently pass it on to others through intimate exchanges. And ultimately, by adulthood, almost everyone has been exposed to EBV, CMV or both.

Therefore, why worry? Use common sense and good health habits like proper hand washing. See a doctor if experiencing severe symptoms or you already have a compromised immune system. But otherwise, chalk up infectious mononucleosis as one of those annoying things that eludes human control. Good common sense and the absence of anxiety is the best course of action.