Table 3.
Variates | No. of LTBI casesa in each category of the contact (%) | Univariable | Multivariable | ||||
---|---|---|---|---|---|---|---|
OR | 95% CI | P value | Adjusted OR | 95%CI | P value | ||
Contacts of index caseb | |||||||
No | 222/565 (39.3) | 1.0 | 1.0 | ||||
Yes | 80/102 (78.4) | 5.6 | 3.4‐9.3 | <.0001 | 4.9 | 2.9‐8.1 | <.0001 |
Contact under CO2 level >1000 ppm | |||||||
No | 57/179 (31.8) | 1.0 | 1.0 | ||||
Yes | 45/488 (50.2) | 2.2 | 1.5‐3.1 | <.0001 | 1.6 | 1.1‐2.3 | .014 |
Abbreviations: CO2, carbon dioxide; LTBI, latent TB infection; OR, odds ratio; ppm, parts per million; TB, tuberculosis.
Number of latent TB infection cases, defined as a positive tuberculin skin test using a cutoff point of 10 mm.
All 102 contacts of the index case were exposed under poorly ventilated environment (CO2 levels >1000 ppm).