Table 1.
Demographics and Clinical Characteristics of Participants by Seropositivity Against SARS-CoV-2 Spike Protein
| Variable | Study Period 1 (n=1,385) August 17–September 4, 2020, Seropositivity 1.9% |
Study Period 2 (n=1,445) December 2–23, 2020, Seropositivity 13.7% |
||||
|---|---|---|---|---|---|---|
| Seropositive (N = 26) |
Seronegative (N = 1359) |
P Value | Seropositive (N =198) |
Seronegative (N = 1247) | P Value | |
| Age, y (SD) | 36 (±11.6) | 40 (±11.8) | .08 | 38.9 (±11.5) | 40.3 (±12) | .13 |
| Sex, no. (%) | .24 | .16 | ||||
| Male | 8 (30.8) | 271 (19.9) | 38 (19.2) | 250 (20.1) | ||
| Female | 18 (69.2) | 1,086 (79.9) | 159 (80.3) | 997 (79.9) | ||
| Other | 0 (0) | 2 (0.2) | 1 (0.5) | 0 (0) | ||
| Race/Ethnicity, no. (%) | .008 | .30 | ||||
| Caucasian | 20 (76.9) | 1,254 (92.3) | 176 (88.9) | 1,127 (90.4) | ||
| Hispanic-Latino | 1 (3.9) | 33 (2.4) | 8 (4) | 31 (2.5) | ||
| Black-African American | 1 (3.9) | 20 (1.5) | 6 (3) | 17 (1.4) | ||
| Asian-Pacific Islander | 0 (0) | 22 (1.6) | 4 (2) | 29 (2.3) | ||
| Arabic-Middle Eastern | 1 (3.9) | 9 (0.7) | 1 (0.5) | 7 (0.6) | ||
| Other | 3 (11.5) | 21 (1.6) | 3 (1.5) | 36 (2.9) | ||
| COVID-19 diagnosis via PCR/antigen, no. (%) | 16 (61.5) | 7 (0.52) | <.001 | 102 (51.5) | 18 (1.4) | <.0001 |
| Symptoms, no. (%) | ||||||
| None | 8 (30.8) | 960 (70.6) | <.001 | 56 (28.3) | 901 (72.3) | <.0001 |
| Fever | 11 (42.3) | 131 (9.6) | <.001 | 44 (22.2) | 58 (4.7) | <.0001 |
| Myalgias | 10 (38.5) | 129 (9.5) | <.001 | 68 (34.4) | 100 (8) | <.0001 |
| Sore throat | 9 (34.6) | 215 (15.8) | .03 | 46 (23.2) | 187 (15) | .0034 |
| Runny nose | 8 (30.8) | 159 (11.7) | .009 | 67 (33.8) | 186 (14.9) | <.0001 |
| Loss of smell | 11 (42.3) | 34 (2.5) | <.001 | 88 (44.4) | 35 (2.8) | <.0001 |
| Cough | 9 (34.6) | 198 (14.6) | .01 | 73 (36.9) | 139 (11.2) | <.0001 |
| Shortness of breath | 7 (26.9) | 102 7.5) | .03 | 40 (20.2) | 58 (4.7) | <.0001 |
| Unusual headaches | 10 (38.5) | 112 (8.2) | <.001 | 66 (33.3) | 110 (8.9) | <.0001 |
| Diarrhea/Upset stomach | 7 (26.9) | 117 (8.6) | .06 | 40 (20.2) | 86 (6.9) | <.0001 |
| Full time (vs part time), no. (%) | 20 (76.9) | 1,059 (77.9) | .90 | 152 (76.8) | 967 (77.6) | .81 |
| Have you practiced public health measures as outlined by MDHHS? No. (%) | .21 | .97 | ||||
| Usually | 23 (88.5) | 1,291 (89.7) | 182 (91.9) | 1140 (91.4) | ||
| Sometimes | 2 (7.7) | 130 (9.6) | 15 (7.6) | 100 (8) | ||
| Rarely | 1 (3.8) | 10 (0.7) | 1 (0.5) | 7 (0.6) | ||
| Have you been exposed to someone with COVID-19? No. (%) | ||||||
| Outside of work but not in your household? | 7 (26.9) | 115 (8.5) | .006 | 48 (24.5) | 181 (14.5) | .0005 |
| Living in your household? | 5 (19.2) | 44 (3.2) | .002 | 43 (21.7) | 90 (7.2) | .0001 |
| Have you worn appropriate PPE at work (congruent with hospital policy)? No. (%) | .76 | .15 | ||||
| Yes | 26 (100) | 1277 (94) | 189 (95.5) | 1,193(95.7) | ||
| No | 0 (0) | 23 (1.7) | 4 (2.5) | 9 (0.7) | ||
| Sometimes | 0 (0) | 58 (4.3) | 5 (2.5) | 45 (3.6) | ||
| Enhanced respiratory protection, No. (%) | .897 | .34 | ||||
| N95 mask | 10 (38.5) | 443 (32.6) | 101 (51) | 594 (47.6) | ||
| CAPRs | 0 (0) | 41 (3) | 7 (3.5) | 24 (1.9) | ||
| Mix of N95/CAPRs | 2 (7.7) | 97 (7.1) | 10 (5.5) | 74 (5.9) | ||
| Not applicable to my role (surgical mask only) | 14 (53.9) | 778 (57.3) | 80 (40.4) | 555 (44.6) | ||
| Providers, no. (%) a | .59 | .73 | ||||
| 1) Clinical provider | 17 (65.4) | 691 (50.9) | 107 (54) | 693 (55.6) | ||
| 2) Interprofessional | 1 (3.9) | 131 (9.6) | 33 (16.7) | 189 (15.2) | ||
| 3) Ancillary | 1 (3.9) | 104 (7.7) | 10 (5.1) | 84 (6.7) | ||
| 4) Nonclinical | 7 (29.9) | 433 (31.9) | 48 (24.2) | 281 (22.5) | ||
| Perceived risk of work exposure, no. (%) | .008 | .26 | ||||
| High | 8 (30.8) | 156 (11.4) | 56 (28.3) | 288 (23.1) | ||
| Moderate | 5 (19.2) | 539 (39.7) | 82 (41.4) | 535 (42.9) | ||
| Low | 13 (50) | 664 (48.9) | 60 (30.3) | 424 (35) | ||
| If you perceived a high risk of exposure at work; why? No. (%) | ||||||
| (N=396). Only asked during study period 2 only patient exposures | 23 (41.1) | 98 (34) | .31 | |||
| Patient exposures + another risk factor | 55 (98.2) | 275 (95.5) | .34 | |||
| Colleague exposures | 24 (42.9) | 142 (49.3) | .38 | |||
| Visitor exposures | 21 (37.5) | 103 (35.8) | .80 | |||
| Perceived lack of PPE or IP policies | 8 (14.3) | 34 (11.8) | .60 | |||
Note. SD, standard deviation; PCR, polymerase chain reaction; MDHHS, Michigan Department of Health and Human Services; PPE, personal protective equipment; CAPR, controlled air purifying respirator; IQR, interquartile range; IP, infection prevention measures.
Providers (clinical providers with most patient exposure): physicians, residents, advanced practice providers (APPs), nurses, medical assistants (MAs), respiratory therapists. Interprofessional services: nutrition/registered dietician (RD), social work, case management, physical therapy (PT), occupational therapist (OT), speech-language pathologist (SLP), pharmacy. Ancillary services: radiology technicians, lab. Nonclinical: clerical, administrative, research, security, food services, maintenance, housekeeping, other.