Table 3. Cox model on risks associated with being an incident case in healthcare workers of the two largest COVID-19 referral hospitals in Mexico City, October 2020-June 2021.
| Variable | Categories | n a | HR | 95% CI |
|---|---|---|---|---|
| Sex | Female | 37 | Reference | |
| Male | 18 | 0.65 | 0.34–1.24 | |
| Age | 0.80 | 0.58–1.10 | ||
| Occupation | Physician | 16 | Reference | |
| Nurse | 16 | 0.94 | 0.40–2.19 | |
| Administrative | 19 | 1.55 | 0.68–3.52 | |
| Other | 4 | 0.23 | 0.06–0.83 | |
| Contact with any person with COVID-19 b | No/Unknown | 7 | Reference | |
| Yes | 48 | 2.45 | 1.21–5.00 | |
| Contact with patients with COVID-19 | Never/Occasionally | 17 | Reference | |
| Frequently | 38 | 1.18 | 0.55–2.50 | |
| Use of PPE | No | 2 | ||
| Yes | 53 | 0.38 | 0.14–1.01 | |
| Use of public transport | No | 30 | Reference | |
| Yes | 25 | 1.30 | 0.68–2.50 |
HR, Hazard ratio; CI, confidence interval; PPE, Personal Protection Equipment
a Total incident cases = 55
b Suspected or confirmed during the last 15 days. Only the variables shown in the table were included in the multivariable model.