Legionnaires' disease: detectable, curable, and preventable; Industry experts Robert F. Whitcomb and Edwin F. Goldstein reveal overlooked facility sources of deadly bacteria.(Focus on Infection Control)

In 1977, it was discovered that Legionnaires' disease (LD), a respiratory illness, was caused by a new family of bacteria. Although we now know how to identify and treat it, many still needlessly die from LD--often in healthcare institutions, including nursing homes. To illustrate, a recent LD outbreak at a Philadelphia nursing home cost the lives offour residents before it was brought under control. (1) In the summer of 2003 there was a dramatic increase in reported cases all along the East Coast that has yet to be explained. (2) This disease can be prevented, if building operators, owners, and managers follow sufficient preventive maintenance procedures. They also should be aware that Legionnaires' disease can be detected and cured, with appropriate and timely procedures.

Background

In 1976, attendees of an American Legion convention in Philadelphia were stricken with a pneumonia-like illness. The cause was traced to a newly discovered bacterium, which soon became known as Legionella pneumophila. (3) This family of bacteria has since been expanded. More than 15 known serogroups have been identified, including LD's less-threatening cousin, Pontiac fever. Fortunately, more sophisticated tests have been developed to diagnose and identify each (4) (figure 1).

Incidents of LD are now commonly reported to disease control centers and in the press, and it is one of the top three causes of community-acquired pneumonia. An estimated 25,000 or more cases occur each year in the United States, with more than 4,000 deaths attributed annually to Legionella pneumophila. It poses such a significant health risk that OSHA has devoted an entire chapter in its Technical Manual to recognizing, investigating, and controlling the disease. (5)

Untreated, LD can reach fatality rates as high as 40%, (6) yet treatments are quite effective if Legionella testing and diagnosis occur at an early stage, when pneumonia is first suspected. LD is most often fatal among adults with lowered immune deficiencies, such as the elderly and those who are hospitalized. Increasingly, cases are…