DEAR DR. DONOHUE: Please explain mononucleosis: how it’s contracted; how it’s diagnosed; how it’s treated. And how long is recovery from it for a 78-year-old woman with bouts of pneumonia? -R.T.

nfectious mononucleosis is a viral infection, and the virus is the Epstein-Barr virus – EB virus.

Most people have a rendezvous with this virus in their youth. By the age of 5, 50 percent of children have evidence in their blood of having been infected with the virus. The evidence is antibodies to the EB virus. Many of these children had no outward signs of illness. For them, it was an undercover illness.

Between the ages of 10 and 20, however, infection with the virus more often causes signs of illness. The infected youngster or young adult has a fever, a sore throat and swollen, tender lymph nodes. A profound fatigue engulfs patients. Muscles ache. The liver and spleen enlarge. The whole affair usually resolves on its own without any medicine in three to four weeks. A washed-out feeling can linger for a few more weeks.

By adulthood, 95 percent of the entire population has antibody evidence of having been infected with the virus. Many of them have no recollection of the illness because it was such a mild, nondescript one.

The mode of transmission is saliva. Once infected, a person can harbor virus in the saliva for as long as a year and a half. So the majority of cases stem not from those who are currently ill but from those who had the illness within the previous year and a half. The saliva transmission gives mono the name “the kissing disease.” But kissing is not the only way of spread, and it might not be the major way of spread. When Army recruits from across the country are herded into common living quarters, any recruit who is carrying the virus without signs of infection can be the source of spread. Kissing is not involved here.

Seventy-eight, while not impossible, is not the usual age for infection. Pneumonia is not usually a consequence of infection. The lady in question should contact an infectious-disease doctor for verification of the diagnosis.

DEAR DR. DONOHUE: My husband has been on the cholesterol-lowering medicine Lipitor for 10 years. His latest lab tests were the best ever. His cholesterol was 157 (4.0). (A normal reading is under 200 or 5.2.) Our doctor suggested a heart scan because both his father and brother had a heart attack at age 42 and a second brother had a six-vessel bypass at age 49. You said: “There are forces other than cholesterol responsible for clogging arteries.” What else causes heart attacks? – M.R.

Artery clogging is responsible for heart attacks, but it is not always a high blood cholesterol level that is responsible for the clogging.

C-reactive protein is an example of a noncholesterol influence on heart disease. Its elevation indicates body inflammation, and, in the setting of heart attacks, artery wall inflammation encourages plaque formation even with a normal blood cholesterol. Homocysteine is an amino acid that indicates artery clogging when its blood levels are high. Social isolation, stress and chronic anger are other factors involved in plugging heart arteries. So is high blood pressure. Your husband’s family is an example of genetic influence, one of the most significant factors in heart artery disease.

In all frankness, there are many unanswered questions about what causes heart artery obstruction.

DEAR DR. DONOHUE: Would you please tell about sundowner’s syndrome? – K.B.

What I think you are referring to is not a syndrome but a symptom that often is part of the spectrum of dementia. Dementia is a deterioration of mental faculties, including memory, orientation with regard to place and time, ability to understand abstract thoughts, and the loss of facility to perform simple, mathematical procedures. There are many dementias, but the most common one is Alzheimer’s disease.

Sundowning is a manifestation of the decline in mental faculties. During the early daytime hours, many people suffering from dementia are at relative peace. In the later afternoon and early evening, they often become agitated and belligerent – sundowning.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475.

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