Table 4.
Incidence rate ratios (IRR) of SARS-CoV-2 following close contact 3-7 days earlier with either patients or co-workers compared with contact with persons outside work with COVID-19.a[CI=confidence interval.]
| Contact with persons with COVID-19 | Person-days | First positive SARS-CoV-2 PCR tests | Infection rate per 100 000 person-days | Model 1 | Model 2 b | Model 3 c |
|---|---|---|---|---|---|---|
|
|
|
|
||||
| IRR (95% CI) | IRR (95% CI) | IRR (95% CI) | ||||
| Patients | 24 203 | 34 | 140.5 | 0.18 (0.11–0.28) | 0.16 (0.10–0.27) | 0.17 (0.10–0.28) |
| Co-workers | 2 738 | 5 | 182.6 | 0.23 (0.09–0.58) | 0.21 (0.08–0.54) | 0.21 (0.08–0.54) |
| Persons outside work | 4 238 | 34 | 802.3 | Reference | Reference | Reference |
a
Only person-days at risk with contact either with patients, co-workers or persons outside work with COVID-19 are included
b
Model 1 adjusted for age (continuous), sex and month (6 categories, November 2020-April 2021)
c
As model 2 and additionally adjusted for number of previous PCR tests.