Table 1.
Factors associated with preferential use of FFP2 vs. surgical masks among 3259 healthcare workers
| Risk or protection factor for SARS-CoV-2 infection | Number of HCW without and with the factor | Frequency of the factor (n and %) in relation to FFP2 use during contact with COVID-19 patients | OR (95% CI) | p value (Fisher's test) | ||
|---|---|---|---|---|---|---|
| Without | With | Mostly surgical mask (n = 2543) | Mostly FFP2 (n = 716) | |||
| Sociodemographic data | ||||||
| Age > 50 years | 2528 | 731 | 604 (24%) | 127 (18%) | 0.69 (0.56–0.86) | 0.001 |
| Sex: male | 2645 | 614 | 444 (17%) | 170 (24%) | 1.47 (1.20–1.81) | < 0.001 |
| Living in Germany or Austria | 3094 | 165 | 104 (4%) | 61 (9%) | 2.18 (1.55–3.06) | < 0.001 |
| Child in household | 2424 | 835 | 650 (26%) | 185 (26%) | 1.01 (0.83–1.23) | 0.884 |
| Medical conditions | ||||||
| Comorbidity | 2066 | 1193 | 921 (36%) | 272 (38%) | 1.08 (0.91–1.28) | 0.404 |
| Active smoker | 2719 | 540 | 426 (17%) | 114 (16%) | 0.94 (0.74–1.18) | 0.649 |
| Pregnant during study | 3122 | 137 | 113 (4%) | 24 (3%) | 0.75 (0.46–1.18) | 0.246 |
| Behaviour outside of work | ||||||
| Prophylactic home remedies | 2787 | 472 | 363 (14%) | 109 (15%) | 1.08 (0.85–1.37) | 0.548 |
| Social leisure activities | 1693 | 1566 | 1208 (48%) | 358 (50%) | 1.11 (0.93–1.31) | 0.253 |
| Wearing a mask outside work | 2354 | 905 | 657 (26%) | 248 (35%) | 1.52 (1.27–1.82) | < 0.001 |
| Support for stronger public restrictions | 2643 | 616 | 433 (17%) | 183 (26%) | 1.67 (1.37–2.05) | < 0.001 |
| HCW specifics | ||||||
| Job: Nurse | 1535 | 1724 | 1309 (51%) | 415 (58%) | 1.30 (1.10–1.54) | 0.002 |
| Job: Physician | 2588 | 671 | 500 (20%) | 171 (24%) | 1.28 (1.05–1.57) | 0.016 |
| Full-time job (> 80%) | 1488 | 1771 | 1325 (52%) | 446 (62%) | 1.52 (1.28–1.81) | < 0.001 |
| Involved in AGP | 2055 | 1204 | 747 (29%) | 457 (64%) | 4.24 (3.55–5.07) | < 0.001 |
| Work in intensive care | 2971 | 288 | 102 (4%) | 186 (26%) | 8.39 (6.43–10.99) | < 0.001 |
| Contact to > 20 COVID-19 patients | 1812 | 1120 | 732 (32%) | 388 (58%) | 2.83 (2.36–3.39) | < 0.001 |
| Behaviour at work | ||||||
| Hygiene knowledge | 491 | 2768 | 2121 (83%) | 647 (90%) | 1.87 (1.42–2.48) | < 0.001 |
| Regular meals in staff restaurant | 1094 | 2165 | 1702 (67%) | 463 (65%) | 0.90 (0.76–1.08) | 0.263 |
| Handwashing more frequent | 343 | 2916 | 2268 (89%) | 648 (91%) | 1.16 (0.87–1.55) | 0.335 |
| Test results | ||||||
| Positive SARS-CoV-2 testa | 2826 | 433 | 352 (14%) | 81 (11%) | 0.79 (0.61–1.03) | 0.081 |
| Negative SARS-CoV-2 testa | 1633 | 1626 | 1231 (48%) | 395 (55%) | 1.31 (1.11–1.55) | < 0.001 |
| Use of PPE | ||||||
| Always used gogglesb | 2362 | 897 | 446 (18%) | 451 (63%) | 7.99 (6.64–9.65) | < 0.001 |
| Always used glovesb | 1939 | 1320 | 904 (36%) | 416 (58%) | 2.51 (2.12–2.99) | < 0.001 |
| Always used a gownb | 2362 | 897 | 437 (17%) | 460 (64%) | 8.65 (7.17–10.46) | < 0.001 |
| Always used FFP2 during AGP | 645 | 559 | 242 (32%) | 317 (69%) | 4.72 (3.65–6.12) | < 0.001 |
FFP2 filtering facepiece class 2, HCW health care worker, AGP aerosol-generating procedure, PPE personal protective equipment, NA not applicable
aAt least one positive/negative test. The mean number of negative tests per HCW was 0.90 for surgical mask users and 1.11 for FFP2 users
bIn contact with COVID-19 patients outside of AGP