Enumeration of Legionella
Quantitative process control with RM-LPNEU1
- Use a quantitative reference material (RM-LPNEU1) with a known number of Legionella pneumophila.
- Defrost the material at room temperature for 30 minutes.
- Mix well before use and dilute the material so countable numbers are inoculated on the media (MWY) by spreading, pour plate or by the membrane filtration method.
- Best results are obtained when a practicable range of 80 cfu to 120 cfu per plate with a minimum number of 50 cfu per plate is used.
- Incubate at (36 ± 2) °C for 2d to 5d.
- Count the colony forming units and register in a control chart.
- The characteristic reaction is: Whitegreybluepurple colonies with an entire edge and exhibiting a characteristic groundglass appearance.