This is at least of the same order of magnitude as the annual rates of 0.45 per 100,000 for hospitalization and 0.043 for death due to scalding by tap water in Quebec ( 9). With the observations from the Stout et al ( 7) study, if active surveillance was performed, an estimated two cases of Legionnaire’s disease per 100,000 people per year could be attributable to potable water in private homes and senior-citizen residences. In an active surveillance study of pneumonia requiring hospitalization in Ohio, the incidence of Legionnaire’s pneumonia was estimated to be approximately seven cases per 100,000 people ( 8).

The importance of Legionnaire’s disease is underestimated because it is difficult to diagnose and b ecause it is reported through a passive surveillance system. The authors concluded that drinking water distribution systems were a significant source of transmission of Legionnaires’ disease ( 7). This included three private homes (one single dwelling, two multidwellings), two senior-citizen homes, two out-patient hospital clinics, and one industrial plant. A link with residential drinking water contamination was established for eight (40%) patients. These findings are supported by Stout et al ( 7) in a study of 20 Pittsburgh patients with culture-confirmed Legionnaires’ disease. However, in a case-control study of sporadic cases of community-acquired legionellosis, Straus et al ( 6) concluded that the residential drinking water supply was responsible for a substantial proportion of sporadic cases of Legionnaires’ disease. The clinical and epidemiological significance of this finding is much debated. The authors concluded that, because of design variables, use of an electric water heater was the most significant factor leading to Legionella contamination in hot water ( 5) in the home. No water heaters using fossil fuels were contaminated ( 5). In Quebec, a study of 211 homes (178 electric water heaters, 33 oil or gas water heaters) found Legionella contamination in 40% of electric water heaters. Although we support prevention against tap water scalds, we are against setting water heater thermostats at 49☌ because we believe this could facilitate proliferation of Legionella inside the tank and increase the risk of legionellosis.ĭomestic water heaters, particularly electric devices, can certainly be contaminated by Legionella. Primary groups at risk (the elderly, smokers, the immunocompromised and patients suffering from chronic respiratory illnesses), are groups who include a large proportion of the population at home.

This is a serious illness associated with high death rates (up to 12%). Like other authors ( 3, 4), including the World Health Organization (WHO) who published a recent monograph on the Legionella problem in drinking water ( 3), we believe that there is evidence for the transmission of legionellosis through the drinking water distribution systems in private homes. Among the means considered to reach this objective, Safe Kids Canada, with the support of some public health organizations, suggests and seems to favour lowering the temperature setting of domestic hot water heaters to 49☌. Scalding by lowering domestic hot water temperature to 49☌ at the tap ( 2). A few months ago, Safe Kids Canada launched a media campaign aimed at preventing

In 1986, this dilemma was the subject of an editorial in the Canadian Inside domestic water heaters exposure to Legionella, the bacteria responsible for Legionnaires’ disease (pulmonary legionellosis), and the risk of scalding. Tab will move on to the next part of the site rather than go through menu items.There are two opposing risks when it comes to water temperature Enter and space open menus and escape closes them as well. Up and Down arrows will open main level menus and toggle through sub tier links. Left and right arrows move across top level links and expand / close menus in sub levels. The site navigation utilizes arrow, enter, escape, and space bar key commands.

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