Table 3. Association between sociodemographic, clinical, and occupational characteristics and SARS-CoV-2 infection in HCWs at Hospital Universitario San Ignacio from March 6, 2020, to February 12, 2021.
| Participant Characteristics | SARS-CoV-2 Cumulative Incidence (n, (%))1 | Crude RR | Adjusted RR2 | Sensitivity analysis3 (Adjusted RR) |
|---|---|---|---|---|
| Sex | ||||
| Female (n = 1940) | 693 (35.7%) | ref | ref | ref |
| Male (n = 657) | 234 (35.6%) | 0.99 | 1.05 | 1.07 |
| Age category (years) | ||||
| <35 (n = 1377) | 546 (39.7%) | ref | ref | ref |
| 35–44 (n = 772) | 252 (32.6%) | 0.82 | 0.84 | 0.85 |
| ≥ 45 (n = 448) | 129 (28.8%) | 0.73 | 0.83 | 0.83 |
| Type of occupation | ||||
| Administrative (n = 571) | 153 (26.8%) | ref | ref | ref |
| Physician (n = 618) | 177 (28.6%) | 1.07 | 0.77 | 0.78 |
| Nurse or nurse assistant (n = 1000) | 478 (47.8%) | 1.78 | 1.20 | 1.17 |
| Other (n = 408) | 119 (29.2%) | 1.09 | 0.90 | 0.88 |
| Main Service | ||||
| Administrative office (n = 373) | 86 (23.1%) | ref | ref | ref |
| Emergency room (n = 392) | 173 (44.1%) | 1.91 | 1.45 | 1.41 |
| General wards (n = 711) | 332 (46.7%) | 2.03 | 1.45 | 1.38 |
| ICU4 (n = 266) | 110 (41.4%) | 1.79 | 1.34 | 1.28 |
| Surgical areas (n = 285) | 76 (26.7%) | 1.16 | 1.04 | 1.04 |
| Ambulatory and diagnostic services (n = 558) | 148 (26.5%) | 1.16 | 1.09 | 1.10 |
| Type of work | ||||
| Non-remote work (n = 2244) | 858 (38.2%) | ref | ref | ref |
| Remote work (n = 304) | 64 (21.1%) | 0.55 | 0.74 | 0.85 |
| COVID-19 work 5 | ||||
| No (n = 1204) | 348 (28.9%) | ref | ref | ref |
| Yes (n = 1342) | 572 (42.6%) | 1.47 | 1.17 | 1.17 |
| Shift | ||||
| Day shift (n = 1690) | 561 (33.2%) | ref | ref | ref |
| Night shift (n = 859) | 361 (42.0%) | 1.27 | 1.07 | 1.07 |
| Type of respiratory protection | ||||
| Surgical or cloth mask (n = 1106) | 386 (34.9%) | ref | ref | ref |
| N-95 respirator (n = 1430) | 529 (37.0%) | 1.06 | 0.82 | 0.83 |
| History of close contact 6 | ||||
| No (n = 1304) | 348 (26.7%) | ref | ref | ref |
| Yes (n = 1219) | 569 (46.7%) | 1.75 | 1.47 | 1.46 |
| Type of transportation 7 | ||||
| Unshared (n = 1235) | 415 (33.6%) | ref | ref | ref |
| Shared (n = 1291) | 497 (38.5%) | 1.15 | 0.97 | 0.98 |
| Smoking in the previous year 8 | ||||
| No (n = 2199) | 788 (35.8%) | ref | ref | ref |
| Yes (n = 317) | 123 (38.8%) | 1.08 | 0.94 | 0.92 |
| Influenza vaccination in the previous year 9 | ||||
| No (n = 1508) | 541 (35.9%) | ref | ref | ref |
| Yes (n = 974) | 342 (35.1%) | 0.98 | 0.94 | 0.96 |
| Body Mass Index (kg/m 2 ) | ||||
| Low or normal (<25), (n = 1503) | 501 (33.3%) | ref | ref | ref |
| Overweight (25.0–29.9), (n = 826) | 324 (39.2%) | 1.18 | 1.18 | 1.15 |
| Obesity (>30), (n = 185) | 81 (43.8%) | 1.31 | 1.24 | 1.20 |
| Comorbidities 10 | ||||
| Non-comorbidity (n = 2098) | 771 (36.7%) | ref | ref | ref |
| Any comorbidity (n = 427) | 146 (34.2%) | 0.93 | 0.99 | 0.97 |
1Row-based percentages.
2aRR: adjusted relative risk. Results from multivariable analysis using log-binomial regression (n = 2,442).
3We evaluated the sensitivity of the results to the definition of seropositivity as a confirmed positive HA result with an additional analysis in which we defined as seropositive any positive HA result. This analysis increased the incident cases from 927 (35.7%) to 976 (37.6%). Here, we present the results of the multivariate sensitivity analysis using log-binomial regression (n = 2,442).
4ICU, Intensive Care Unit.
5HCWs who worked in the COVID area any time since March 2020.
6HCWs who were less than 6 feet away from an infected person (laboratory-confirmed or a clinical diagnosis) for a total of 15 min without personal protective equipment, at any time since March 2020.
7Shared transportation was defined as the use of any public or collective transport.
8History of smoking in the previous year.
9History of influenza vaccination in the previous year.
10Self-reported pre-existing medical condition. HCW, healthcare worker.