Table 2. Workplace and Community Behaviors of Health Care Personnel Who Tested Positive for SARS-CoV-2 and Had One or More Symptoms of Covid-19–like Illness (Case Participants) and Those Who Tested Negative (Control Participants).
| Variable | Case Participants (N=1482) |
Control Participants (N=3449) |
Standardized Difference* |
|---|---|---|---|
| Anticipated level of patient contact, assessed on the basis of job category — no. (%)† | |||
| Substantial direct patient contact | 918 (62) | 2227 (65) | 0.0545 |
| Moderate direct patient contact | 168 (11) | 394 (11) | 0.0028 |
| Minimal direct patient contact | 340 (23) | 702 (20) | 0.0629 |
| Undefined patient contact | 56 (4) | 126 (4) | 0.0066 |
| Community behaviors 14 days before symptom-onset date or test date — no. (%) | |||
| Had close contact with a person with Covid-19 outside the health care setting‡ | 665 (45) | 638 (18) | 0.5911 |
| Had close contact with any ill person outside a health care facility‡ | 518 (35) | 731 (21) | 0.3098 |
| Attended a gathering that included persons other than household members | 390 (26) | 753 (22) | 0.1050 |
| Used public or shared transportation | 225 (15) | 650 (19) | 0.0976 |
| Attended or worked at a school or day care | 72 (5) | 201 (6) | 0.0431 |
| Had a household member who attended school or day care | 367 (25) | 998 (29) | 0.0942 |
| Workplace behaviors | |||
| Had close contact with a person with Covid-19 who was not a patient — no. (%) | 250 (17) | 624 (18) | 0.0322 |
| Had close contact with a patient with Covid-19 during work in health care facility — no. (%) | 479 (32) | 1142 (33) | 0.0168 |
| Used personal protective equipment appropriately — no./total no. (%)§¶ | 206/479 (43) | 519/1142 (45) | 0.0326 |
| Participated in aerosol-generating procedures for patients with Covid-19 — no./total no. (%)§‖ | 180/479 (38) | 434/1142 (38) | 0.0133 |
| Had exposure to patients with Covid-19 who were not intubated or wearing face coverings — no./total no. (%)§ | |||
| All or most of the time | 129/479 (27) | 308/1142 (27) | 0.0080 |
| Sometimes | 60/479 (13) | 170/1142 (15) | 0.0425 |
| Rarely or never | 83/479 (17) | 250/1142 (22) | 0.0672 |
| Not sure | 207/479 (43) | 414/1142 (36) | 0.0585 |
| Reason for SARS-CoV-2 test — no. (%)** | |||
| Occupational exposure in the workplace | 192 (13) | 493 (14) | 0.0390 |
| Exposure outside the workplace | 327 (22) | 449 (13) | 0.2396 |
| Routine screening, with no symptoms | 63 (4) | 541 (16) | 0.3888 |
| Presence of symptoms | 1182 (80) | 2229 (65) | 0.3426 |
| Other** | 14 (1) | 97 (3) | 0.1379 |
| Reported previous positive result of serologic test during study interview — no. (%) | 17 (1) | 14 (<1) | 0.0845 |
The standardized difference shows the difference in means in units of the pooled standard deviation (Section E in the Supplementary Appendix).
Job categories that were associated with anticipated substantial direct patient contact included the following: physician, physician assistant, nurse practitioner, registered nurse, licensed practical nurse, other nurse, certified nursing assistant, patient care technician or assistant, medical assistant, coronavirus disease 2019 (Covid-19) tester, phlebotomist, home health personnel, emergency medical services provider, physical therapist or assistant, rehabilitation aide, occupational therapist, speech–language pathologist, respiratory therapist, radiology technician, dental health care provider, and surgical, medical, or emergency technician. Job categories that were associated with anticipated moderate direct patient contact included the following: environmental services personnel, food services personnel, patient transport personnel, nonphysician behavioral health provider, chaplain, care coordinator, translator, health educator, genetic counselor, dietitian, and research personnel. Job categories that were associated with minimal patient contact included the following: administrative or ward clerk, symptom checker, telehealth trainer, facilities maintenance equipment and sterile technician, medical equipment salesperson, laboratory personnel, and pharmacist. Undefined patient contact included other health care personnel who could not be classified into any of the above categories and those with missing information.
Close contact was defined as being within approximately 6 ft (approximately 2 m) of a person with Covid-19 for at least 15 minutes or having unprotected direct contact with potentially infectious secretions or excretions.
This measure was assessed among participants who reported close contact with patients with Covid-19 during work.
Appropriate use of personal protective equipment during care for patients with Covid-19 was defined as the wearing of an N95 mask or powered air-purifying respirator, gown, gloves, and face shield or goggles at all times.
Aerosol-generating procedures were defined as follows: airway suctioning, breaking the ventilation circuit (intentionally or unintentionally), bronchoscopy, chest physiotherapy, cardiopulmonary resuscitation, high-flow oxygen delivery (whether by nasal cannula or mask), high-frequency oscillatory ventilation, intubation, mini–bronchoalveolar lavage, manual (bag) ventilation, nebulizer treatments, noninvasive positive-pressure ventilation (e.g., bilevel positive airway pressure or continuous positive airway pressure), sputum induction, and other procedures that might result in the generation of aerosols.
Reasons for testing are not mutually exclusive. Other reasons for testing included screening before or after travel, testing because of symptoms after receipt of a Covid-19 vaccine, or not specified.