Leila Rich wrote:I have no idea why, but Australasia has really high infection rates. Check this out!
The bacteria are also common in bagged compost/potting mix, and there's always warnings to avoid inhaling when opening bags.
Cooling towers in air conditioning systems are the most common culprit. This snippet from Wikipedia shows critical temperature range. Locations that contain many antiquated AC systems give many opportunities for infection. The bacteria are endemic almost everywhere. Population levels are related to temperature. The natural environment in many places can spend long periods in the critical temperature range. Everything from rain barrels to bags of
compost to water left in the bathtub would be at the right temperature for a population explosion.
* Above 70 °C (158 °F) - Legionella dies almost instantly
* At 60 °C (140 °F) - 90% die in 2 minutes (Decimal reduction time (D) = 2)
* At 50 °C (122 °F) - 90% die in 80–124 minutes, depending on strain (Decimal reduction time (D) = 80-124)
* 48 to 50 °C (118 to 122 °F) - Can survive but do not multiply
* 32 to 42 °C (90 to 108 °F) - Ideal growth range
* 25 to 45 °C (77 to 113 °F) - Growth range
* Below 20 °C (68 °F) - Can survive but are dormant, even below freezing
Whole article ---
http://en.wikipedia.org/wiki/Legionella