Frequently Asked Questions
Legionella
You should use Genomadix’s on-site Legionella test because it is the fastest and most accurate method for early detection and disinfection of Legionella. It provides results in 45 minutes and uses qPCR technology that is the gold standard in medical diagnostics. In contrast, Legionella culture leaves your building exposed to the risk of Legionella outbreaks. The first problem is that Legionella are slow-growing bacteria and it takes 10-14 days to get a result. This is too slow because Legionella can grow to outbreak levels of 1,000 bacteria/mL in as few as seven days.
The second problem is that culture is highly inaccurate. For example, the CDC conducted a proficiency study of ELITE-certified Legionella culture testing labs and found the culture labs undercounted the actual Legionella concentrations by an average of 1.25 logs (17-fold) and values differed between labs by 0.78 logs (6-fold).
Legionella can be found in all water sources, including cooling towers, domestic hot water systems, humidifiers, and fountains. From 2000-2014, the CDC investigated 38 outbreaks of Legionnaires’ disease. The top three sources of exposure were potable water (56%), cooling towers (22%), and hot tubs (7%)
We proved this by collecting water samples on-site and testing them immediately with Spartan’s test and in parallel with on-site culture. The results from both on-site tests were equivalent.
We recommend you perform the Genomadix test weekly because Legionella bacteria can grow to outbreak levels of 1,000 bacteria/mL within seven days. This is why Legionella testing regulations such as PWGSC MD 15161 and New York City’s Local Law 77 require weekly testing with dipslides. The problem with dipslides is they have extremely poor performance.
The second problem is that culture is highly inaccurate. For example, the CDC conducted a proficiency study of ELITE-certified Legionella culture testing labs and found the culture labs undercounted the actual Legionella concentrations by an average of 1.25 logs (17-fold) and values differed between labs by 0.78 logs (6-fold).
