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You are here: / Home / Knowledge / Guidance / Legionnaires Disease History

The History of Legionnaires’ Disease

History of Legionnaires disease

A review of the history of the infection known as Legionnaires’ disease reveals that it can be traced back as far as 1976, to a convention of the American Legion (a veterans association similar to the British Legion) in Philadelphia in America. While the reason for the convention was supposed to be a celebration of the 200th anniversary of America’s position as an independent nation, it would be remembered for entirely different reasons.

Just one day into the convention, people in attendance began to be taken ill with symptoms not unlike those of pneumonia. Many of those at the convention were members of the American Legion, and by the end of the outbreak, 29 members of the Legion had lost their lives. In total, 34 were confirmed to have died from the illness while 221 in total had become ill.

The deadly effects of legionella bacteria

Of course, the Legionella bacterium existed long before 1976. However, it was the outbreak in Philadelphia that led the illness associated with it to be called Legionnaires’ disease after the American Legionnaires’ it affected. Furthermore, the same bacterium was confirmed to be the cause of the illness, and of an earlier outbreak of Pontiac fever that had developed in 1968. That fever was so-called because it broke out in Pontiac in Michigan.

Is Legionnaires’ disease more common in summer?

America’s Center for Disease Control (CDC) confirms cases of Legionnaires’ disease tend to peak in summer and early autumn when external temperatures are usually at their highest. They do however state they can occur throughout the year. It took the CDC six months to identify and confirm legionella to have caused the outbreak at the convention. Many other theories for the illness had already been ruled out by that point.

Were there earlier cases of the disease?

Once the reason for the outbreak was confirmed, it was easier to look back in history to try and identify other outbreaks that had already occurred, but for which a reason had not yet been confirmed. The earliest date discovered for an outbreak of Legionnaires’ was as far back as 1957, but it is likely there will have been earlier examples of the Legionella bacterium causing illness as well.

No respect for international boundaries

Outbreaks of the disease continue to flare up from regularly, both in the US and in other countries around the world. As medical and health and safety professionals have grown to understand more about Legionnaires’ disease, and to understand the development of the Legionella bacterium that causes it, we can put measures into place to try and prevent outbreaks from occurring.

Legionnaires disease is preventable

Nowadays, it is far less likely outbreaks will occur providing health and safety rules are followed. The disease is considered as preventable by most health and safety authorities around the world and it is only when maintenance and other control measures fail or are not completed, or tests are not done regularly, that legionella has the chance to multiply and spread to the extent that it may cause harm to people.

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For additional information about legionella bacteria and Legionnaires’ disease … here
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