Gettysburg Medical News
 The Clinical View
 by P.E. Hoffsten, MD
2 November 2005

THE FUSS ABOUT LEGIONNAIRES DISEASE

            From July 21^st to July 24^th , 1976, the Pennsylvania component of the American Legion held in convention in Philadelphia, Pennsylvania.  By the 16^th of August, approximately three weeks later, there had been 182 cases of pneumonia of which 29 individuals died.  This was a 16% fatality rate for this epidemic of pneumonia.  The Health Department studied this epidemic very carefully and subsequently discovered a new bacteria previously unidentified as causing pneumonia.  As you might imagine, the new bacteria was named Legionella pneumophila. This bacteria was subsequently traced to the water on the roof of the hotel in which these American Legion attendees stayed.  As you might imagine, the hotels business did poorly for the next several months.  The bacteria responsible for this pneumonia epidemic was not sensitive to the usual antibiotics that were used in 1977.  However, it was found that the bacteria was sensitive to an antibiotic called Erythromycin.  This antibiotic causes abdominal discomfort in many people and is infrequently used.  Thus, it was not a staple commonly used antibiotic for pneumonias in 1976 when the Legionnaires epidemic occurred.  Since then, the use of a antibiotic of the Erythromycin family has become relatively standard treatment when an individual is seen with “community acquired pneumonia”.

            Community acquired pneumonia refers to a condition in which the person was previously well with no expectation of illness.  The person develops a fever, most often associated with a cough.  The fever is usually associated with a shaking chill and the person generally knows that they have something besides “a little flu”.  The cough develops a pussy yellow or green sputum, often associated with blood in the sputum.  The person becomes unable to function normally relatively quickly and accept for the standard South Dakota male, will seek medical attention.  Standard South Dakota males are generally carried to medical attention after they collapse.

            Once the person seeks medical attention and a community acquired pneumonia is diagnosed, standard antibiotic therapy in today’s medical practice includes antibiotics that will effectively treat Legionella pneumophila.  To this time, antibiotic resistance in this species of bacteria has not been a major problem.  In today’s world in South Dakota, mortality from Legionnaires disease is relatively low compared to mortality rates for some other species of bacteria.  For the elderly debilitated and those with chemotherapy for malignancies or HIV infection, mortality can approach 50% because the real defense against Legionella pneumophila is a person’s own natural resistant system.  Antibiotics merely slow down the bacteria’s rate of growth until the bodies natural defenses catch up and eradicate the infection.

            Recently, there has been a “epidemic” of eleven cases of Legionella pneumonia recognized in Rapid City.  Our State Health Department and specifically, the Secretary of Health, Donning Hollingsworth, has been criticized for not “covering up” or “failing to report” the infection.  Nothing could be further from the truth.  Our State Health Department and its leaders do an excellent job of extending information to the public attempting to control and prevent disease.  To say that they are failing to communicate is simply not true.

            What then is the problem with Legionnaires disease in Rapid City.  Why there and not in Sioux Falls or Pierre or Gettysburg?  The answer has to do with the sporadic shotgun distribution of Legionella pneumophila.  This bacteria occurs in 30% of homes randomly surveyed looking for it.  The disease however, is remarkably uncommon.  After the 1976 outbreak of the disease in Philadelphia, blood tests were done on samples taken from individuals who had had pneumonia many years before and it was found that this disease had been present for many years but simply not recognized.  There does not appear to be a predictable profile for individuals who develop the sporadic cases of Legionnaires disease.  There is not a realistic expectation that we are going to eradicate this bacteria from our environment.  Cutting down potential exposures by avoiding stagnant water is home is a theoretical measure taken to rid our homes of this bacteria.  But to this time, there is no evidence based information that would say this prevents the disease that still occurs sporadically in our population.  To this time, there has not been a common source identified for the cases occurring Rapid City.  As chance would have it, one or two or three causes were occurred and were recognized and then the healthcare system became more aware of the condition and therefore were more aware of the condition.  Therefore they looked for it more frequently and of course, found it more frequently.

            The one predictable situation leading to a bad outcome is delay of treatment.  When the person with the condition feels that they have “just a little cold” or “they will get over it quickly”, they are playing a dangerous game.  The longer the person waits before being treated for Legionnaires disease , the more likely the condition is to be serious and even fatal.  The disease is always diagnosed by blood tests or sputum tests but are not available at the time action needs to be taken.  Thus, the use of Legionnaires disease effective antibiotic at the moment of diagnosis of a community acquired pneumonia is a pivotal step in care.  The healthcare professionals at your local clinics are well aware of this rule.  With the Rapid City experience, they are now even more aware of this rule.  To my knowledge, the central South Dakota has been spared from this problem at this time.

            Of all the pneumonias that occur, plan old garden variety pneumococcal is still by far the most common.  Legionnaires disease makes up less than 1% of all the cases of pneumonia that ever occur.  This winter and next, the looming catastrophe is the potential for the bird flu epidemic.  Thus far, this has not developed in humans but our Health Department personnel keep warning that the bird flu epidemic is coming.  Preparations of vaccines that will be administered to the broad public this fall will not cover the bird flu strain that is out there.  A new vaccine to cover that specific strain of influenza virus in development.  Getting your shot when that becomes available will be lifesaving for many, many people.