Is Legionnaires’ Disease a Problem in Canada?

0 Flares 0 Flares ×

Prevent risk of Legionella sign

Legionella warning sign

Legionnaires’ disease is caused by Legionella bacteria. It is a potentially fatal respiratory disease characterised by severe pneumonia. At least 50 species and 70 strains (serotypes) of Legionella bacteria have been identified.

Over 90% of Legionnaires’ disease cases are caused by Legionella pneumophila. The first recorded outbreak of Legionnaires’ disease was in 1976 in Philadelphia, Pennsylvania, USA where several people who went to a convention of the American Legion got infected and 35 of them died.

Another outbreak is however believed to have occurred in the same venue in 1974. Since the 1976 outbreak, more and more cases of Legionnaires’ disease outbreaks have been reported in other parts of the world including Australia, United Kingdom, The Netherlands, Spain, Canada, Norway, New Zealand and German. Medical experts say that there is a general increase in the number of Legionnaires’ cases in North America. cases have significantly increased over the last decade.

Is Legionnaires’ Disease a Problem in Canada?

A search for Canadian national statistics for Legionnaires disease or Legionella did not show any records but according to Health Canada, the average number of reported cases of Legionnaires’ disease is generally less than 100 per year. However the actual number of cases is thought to be much higher, as many people with pneumonia may not be tested for infection with Legionella

Medical experts say cases of legionnaires’ disease have steadily increased in North America and Europe for the past decade. According to the public health officials, by July 2013, Toronto had five times as many cases of legionnaires’ disease within the past six weeks compared to the same time in 2012.

Legionella Colonies

Legionella Colonies

In the US, between 8,000 and 18,000 people are infected with Legionella every year, according to the Centers for Disease Control and Prevention (CDC).

Single cases of Legionnaires’ disease are more common than out-breaks. Outbreaks occur in large institutional buildings, especially hotels and hospitals, or on cruise ships. There has been 2 major outbreaks of Legionnaires’ disease in Canada.

The first was in late September 2005 when one hundred and twenty-seven residents of a nursing home in Toronto were infected with Legionella pneumophila and within a week, 21 of the residents had died. The source of the outbreak was traced to the air-conditioning cooling towers on the nursing home’s roof.

More recently in September 2012, there was an outbreak of Legionnaires’ disease in Quebec City, Quebec. A hundred and eighty (180) people were affected and 13 of them died. This outbreak was associated with contamination of water in industrial cooling towers.

Therefore Mold & Bacteria Consulting Laboratories conclude that Legionnaires’ disease is becoming a problem in Canada. As part of due diligence, institutions operating hot and cold water systems should considered monitoring for Legionella bacteria on a regular basis.

For sample analysis please click Legionella Testing Laboratory

0 Flares Twitter 0 Facebook 0 LinkedIn 0 0 Flares ×
The following two tabs change content below.
Dr Jackson Kung'u
Dr. Jackson Kung’u is a Microbiologist who has specialized in the field of mycology (the study of moulds and yeasts). He is a member of the Mycological Society of America. He graduated from the University of Kent at Canterbury, UK, with a Masters degree in Fungal Technology and a PhD in Microbiology. He has published several research papers in international scientific journals. Jackson has analyzed thousands of mould samples from across Canada. He also regularly teaches a course on how to recognize mould, perform effective sampling and interpret laboratory results. Jackson provides how-to advice on mould and bacteria issues. Get more information about indoor mould and bacteria at

Join Us to Get Free News and Tips

Mold and bacteria testing tips, news and insights that we only share with our private newsletter subscribers.




No thanks, I don't need today's most important news.
905 290 9101
0 Flares Twitter 0 Facebook 0 LinkedIn 0 0 Flares ×

Free Report Reveals Simple Ways to Improve Your Lab Results

This free 16-page report was written to provide you with the information we've learned after decades of analysis and interpretation.

  • 3 simple ways to improve laboratory reports
  • Understanding terminology used in laboratory reports
  • How to interpret laboratory results for airborne fungal samples
  • And much more...
Close this popup

Enter your email address below to get instant access