Volume 11, Number 3—March 2005
Research
Probable Psittacosis Outbreak Linked to Wild Birds
Table 2
Multivariable logistic regression model of potential risk factors for psittacosis among 48 case-patients and 310 controls in the Blue Mountains outbreak, Australia
Potential risk factors for psittacosis | Adjusted* OR (95% CI)† | p value |
---|---|---|
Age group (y) | ||
15–49 | Referent | |
50–64 | 3.9 (1.5–10.5) | 0.006 |
65–75 | 2.8 (0.9–8.8) | 0.08 |
Resident of the upper Blue Mountains | 15.2 (5.6–41.7) | <0.0001 |
History of asthma | 0.1 (0.01-0.8) | 0.03 |
Level of contact with free-ranging (wild) birds | ||
No contact | Referent | |
Only indirect contact | 2.6 (1.0–7.3) | 0.06 |
Any direct contact | 7.4 (2.5–22) | 0.0003 |
Contact with caged or domestic birds | 0.2 (0.04–0.8) | 0.02 |
Lawn mowing | ||
Did not mow lawn | Referent | |
Only mowed lawn with a grass catcher | 0.4 (0.1–1.3) | 0.12 |
Mowed lawn without a grass catcher | 3.2 (1.3–8.0) | 0.01 |
Potting or weeding | 0.2 (0.1–0.5) | 0.001 |
*After adjustment for the effects of age group, sex, region of residence, outdoor employment, history of asthma, level of free-ranging (wild) bird contact, contact with caged or domestic birds, lawn mowing, potting or weeding, smoking history, general health self-rating, duration lived in the Blue Mountains, soft landscaping, hard landscaping, using compost, and residence adjacent to bushland.
†OR, odds ratio; CI, confidence interval.