Skip to main content

Table 3 Distribution of Legionella spp. by concentration (cfu/L) according to chlorination stages

From: Legionella control in the water system of antiquated hospital buildings by shock and continuous hyperchlorination: 5 years experience

  < 102 cfu/L > 102 < 103 cfu/L > 103 cfu/L Total
Before hyperchlorination 9 (4.4%) 21 (10.3%) 13 (6.4%) 43/204 (21.1%)
15 days after hyperchlorination 8 (4.1%) 2 (1.0%) 5 (2.6%) 15/193 (7.8%)
30 days after hyperchlorination 0 4 (2.3%) 2 (1.2%) 6/173 (3.5%)
Continuous hyperchlorination 8 (1.9%) 5 (1.2%) 10 (2.4%) 23/416 (5.5%)
No continuous hyperchlorination 13 (23.6%) 2 (3.6%) 0 15/55 (27.3%)*
Total 38 34 30 102
  1. *Odds Ratio = 6.41, 95% CI 3.10 - 13.26; p < 0.001 no continuous hyperchlorination compared with continuous hyperchlorination.