SPL study disproves claims of variability and viability in Legionella testing

CLAIM: Major changes occur in Legionella between collection and testing.
STUDY: In building water samples, we found no significant change in Legionella count between sample collection up to 48 hours after collection.

CLAIM: Legionella counts vary from site to site.
STUDY: No significant difference in Legionella concentrations among 12 outlets over 13 sampling dates.

CLAIM: Percent positivity not dependable tool.
STUDY: Extent of colonization (percentage of outlets positive) was stable over the study period. This shows reliability for environmental assessment.

Legionella is stable over time. Samples should be received within 48 hours. Rely on Legionella culture, the gold standard, for Legionella testing (ISO 117231).