Volume 8, Number 1—January 2002
Research
A Large Outbreak of Legionnaires’ Disease at a Flower Show, the Netherlands, 1999
Jeroen W. Den Boer*†
, Ed P.F. Yzerman‡, Joop Schellekens*, Kamilla D. Lettinga§, Hendriek C. Boshuizen*, Jim E. Van Steenbergen¶, Arnold Bosman*, Susan Van den Hof*, Hans A. Van Vliet*, Marcel F. Peeters#, Ruud J. Van Ketel§, Peter Speelman§, Jacob L. Kool*, and Marina A.E. Conyn Van Spaendonck*
, Ed P.F. Yzerman‡, Joop Schellekens*, Kamilla D. Lettinga§, Hendriek C. Boshuizen*, Jim E. Van Steenbergen¶, Arnold Bosman*, Susan Van den Hof*, Hans A. Van Vliet*, Marcel F. Peeters#, Ruud J. Van Ketel§, Peter Speelman§, Jacob L. Kool*, and Marina A.E. Conyn Van Spaendonck*Table 2
Results of univariate analysis of data from questionnaires and drawings comparing host factors and visits with specific sites at the exhibition for cases and controls.
| Study population | Respondents' questionnaire and set of drawings; univariate ORa (95% CI) (101 cases, 119 controls) | Respondents' questionnaire and set of drawings; raw data (101 cases, 119 controls) |
|---|---|---|
| Age | 1.1 (1.0 - 1.1) | na |
| Male | 2.7 (1.6 - 4.7) | 63/45 |
| Underlying disease | 7.2 (1.5 - 33.1) | 11/2 |
| Smoking | 2.0 (1.1 - 3.6) | 42/31 |
| Total hours at exhibition | 1.7 (1.4 - 2.1) | 4/3 |
| Hours at consumer exhibition | 1.0 (0.8 - 1.3) | 1/1 |
| Pausing at whirlpool spa in hall 3 | 4.2 (1.9 - 9.0) | 41/21 |
| Pausing at bubblemat in hall 3 | 3.7 (1.6 - 8.2) | 37/17 |
| Pausing in gangway of bubblemat in hall 3 | 0.4 (0.2 - 1.0) | 24/35 |
| Pausing at electric kettle in hall 3 | 3.0 (1.3 - 7.0) | 26/12 |
| Pausing at whirlpool in hall 4 | 2.4 (1.1 - 5.4) | 31/20 |
| Pausing at steam iron in hall 4 | 5.4 (1.4 - 22.0) | 16/3 |
aOR = odds ratio; CI = 95% confidence intervals; na = not available.
1A bubblemat is an inflatable rubber mat that causes a whirlpool-like effect when placed in a normal bathtub.
