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An Ottawa company that tests for infection-causing bacteria says the germs that cause Legionnaires’ disease went above acceptable levels in more than one-third of federal government buildings it sampled last summer.
Four of the 51 buildings tested were at least 10 times over the limit for Legionella bacteria. One building was at least 100 times over the limit.
But none of the buildings are being publicly identified by Public Services and Procurement Canada, which sponsored the research.
Legionnaires’ disease is a severe form of pneumonia caused by a natural bacterium called legionella, which multiplies in the warm, humid environment of big ventilation systems.
The bug can spread through the moisture in ventilation, but not from person to person. It is named for the 1976 convention of the American Legion in Philadelphia where it was first identified. It killed 29 people there.
This newspaper asked Public Services and Procurement Canada which buildings were tested and the results of those tests. PSPC did not respond to this newspaper’s questions.
Spartan Biosciences of Ottawa participated in the 12-week test comparing its technology, which does DNA testing in about 45 minutes, with traditional “culture” tests. A culture test involves taking a sample and shipping it to a lab, which takes up to two weeks to grow more bacteria and then count them.
But there’s a problem with cultures. Legionella bacteria can die during the shipping, which results in a false “all-clear” result.
Paul Lem, Spartan’s chief executive officer, says the traditional testing gave false negative readings (i.e. it missed bacteria that were present) about 62 per cent of the time in the trial last summer.
The U.S. Centers for Disease Control and Prevention have found that tests for the bacterium can underestimate its numbers by 10 times or more.
“Back in 2013 they (the CDC) actually wanted to make on-demand DNA testing the standard, but the technology didn’t exist,” he said.
The PSPC project ran from August to October, with 650 tests in 51 buildings. Buildings were in Ottawa, Toronto and Montreal, but are not identified in the study.
The tests examined water in cooling towers on the roof — big tanks that absorb heat pumped out by the ventilation systems. The warm water can breed bacteria quickly, and regulations call for regular testing, because water droplets from the cooling tower can be recirculated back into the building’s air.
“The results are shocking,” Lem said. “We have 39 per cent of these cooling towers in buildings that are above 10 bacteria per millilitre. That’s the action level where you go and disinfect buildings. And eight per cent had levels 10 times higher than that,” requiring a more extensive cleanup.
The company adds in a release that “four out of 51 cooling towers attached to federal buildings had so much of the disease-causing Legionella bacteria they would have to be flushed out with disinfectant, according to existing standards. That was despite the fact Ottawa has one of the world’s most stringent Legionella-testing regimes.”
Lem said disinfection involves chlorine “shock” treatment, similar to a swimming pool.
Lem, a medical doctor who began a residency in infectious diseases before moving on to Spartan, said he would not want to work in one of the buildings with high bacterial counts.
Public Health Ontario says this province had 203 confirmed cases of Legionnaires’ disease in the past year, similar to numbers for mumps and meningitis.
It does not break down numbers by city.
“It’s troubling to see harmful levels of Legionella found in any federal building, and we expect all safety precautions to be put in place immediately once discovered,” Robyn Benson, president of the Public Service Alliance of Canada, said in a statement.
She wants monitoring done every week in warm weather when bacteria are more likely to multiply. She also wants consultation with health and safety committees.
A Legionnaires’ outbreak in Quebec City killed 13 people in 2013, and another killed 16 in New York in 2015.
Lem argues it is likely that there are more cases that are not recognized. The disease causes pneumonia symptoms, and he says it is likely that some of the pneumonia cases in hospitals are caused by this bacterium, but are not identified specially as Legionnaires’.
The bacterium is natural he said, with “low levels in lakes and streams and in the soil.” But the warm water of a cooling tower gives them a chance to multiply.
tspears@postmedia.com
twitter.com/TomSpears1
By the numbers:
51 Federal buildings tested in 2017
31 Buildings with cooling towers within acceptable limit
20 Buildings above acceptable limit
4 Buildings at least 10 times over the limit
1 Building at least 100 times over the limit
203 Known cases of Legionnaires’ disease in Ontario in past 12 months.
查看原文...
Four of the 51 buildings tested were at least 10 times over the limit for Legionella bacteria. One building was at least 100 times over the limit.
But none of the buildings are being publicly identified by Public Services and Procurement Canada, which sponsored the research.
Legionnaires’ disease is a severe form of pneumonia caused by a natural bacterium called legionella, which multiplies in the warm, humid environment of big ventilation systems.
The bug can spread through the moisture in ventilation, but not from person to person. It is named for the 1976 convention of the American Legion in Philadelphia where it was first identified. It killed 29 people there.
This newspaper asked Public Services and Procurement Canada which buildings were tested and the results of those tests. PSPC did not respond to this newspaper’s questions.
Spartan Biosciences of Ottawa participated in the 12-week test comparing its technology, which does DNA testing in about 45 minutes, with traditional “culture” tests. A culture test involves taking a sample and shipping it to a lab, which takes up to two weeks to grow more bacteria and then count them.
But there’s a problem with cultures. Legionella bacteria can die during the shipping, which results in a false “all-clear” result.
Paul Lem, Spartan’s chief executive officer, says the traditional testing gave false negative readings (i.e. it missed bacteria that were present) about 62 per cent of the time in the trial last summer.
The U.S. Centers for Disease Control and Prevention have found that tests for the bacterium can underestimate its numbers by 10 times or more.
“Back in 2013 they (the CDC) actually wanted to make on-demand DNA testing the standard, but the technology didn’t exist,” he said.
The PSPC project ran from August to October, with 650 tests in 51 buildings. Buildings were in Ottawa, Toronto and Montreal, but are not identified in the study.
The tests examined water in cooling towers on the roof — big tanks that absorb heat pumped out by the ventilation systems. The warm water can breed bacteria quickly, and regulations call for regular testing, because water droplets from the cooling tower can be recirculated back into the building’s air.
“The results are shocking,” Lem said. “We have 39 per cent of these cooling towers in buildings that are above 10 bacteria per millilitre. That’s the action level where you go and disinfect buildings. And eight per cent had levels 10 times higher than that,” requiring a more extensive cleanup.
The company adds in a release that “four out of 51 cooling towers attached to federal buildings had so much of the disease-causing Legionella bacteria they would have to be flushed out with disinfectant, according to existing standards. That was despite the fact Ottawa has one of the world’s most stringent Legionella-testing regimes.”
Lem said disinfection involves chlorine “shock” treatment, similar to a swimming pool.
Lem, a medical doctor who began a residency in infectious diseases before moving on to Spartan, said he would not want to work in one of the buildings with high bacterial counts.
Public Health Ontario says this province had 203 confirmed cases of Legionnaires’ disease in the past year, similar to numbers for mumps and meningitis.
It does not break down numbers by city.
“It’s troubling to see harmful levels of Legionella found in any federal building, and we expect all safety precautions to be put in place immediately once discovered,” Robyn Benson, president of the Public Service Alliance of Canada, said in a statement.
She wants monitoring done every week in warm weather when bacteria are more likely to multiply. She also wants consultation with health and safety committees.
A Legionnaires’ outbreak in Quebec City killed 13 people in 2013, and another killed 16 in New York in 2015.
Lem argues it is likely that there are more cases that are not recognized. The disease causes pneumonia symptoms, and he says it is likely that some of the pneumonia cases in hospitals are caused by this bacterium, but are not identified specially as Legionnaires’.
The bacterium is natural he said, with “low levels in lakes and streams and in the soil.” But the warm water of a cooling tower gives them a chance to multiply.
tspears@postmedia.com
twitter.com/TomSpears1
By the numbers:
51 Federal buildings tested in 2017
31 Buildings with cooling towers within acceptable limit
20 Buildings above acceptable limit
4 Buildings at least 10 times over the limit
1 Building at least 100 times over the limit
203 Known cases of Legionnaires’ disease in Ontario in past 12 months.
查看原文...
