Burden of COVID-19 among HCWs

In the provincial database, 54,005 confirmed COVID-19 cases occurred between March 1 and June 14, 2020, and 13,726 (25.4%) of these were HCWs. This proportion increased from 19.6% in early spring to 28.7% in mid-spring and declined to 25.5% by late spring (Fig. 1). The estimated rate of reported COVID-19 was 11 times greater in HCWs compared to non-HCWs aged 20–69 years (4.4% vs 0.4%). By occupation, the COVID-19 rate was highest among healthcare support workers (7.3%) and nurse assistants (7.4%), and it was lower in nurses (4.2%) and physicians (1.8%) (Fig. 2).

Fig.1.

Number and percentage of reported COVID-19 cases, reported infected healthcare workers and participants to the study per day of symptom onset (or day of testing) and proportion of healthcare workers among all reported infections.

Note. HCW, healthcare worker.

Fig. 2.

COVID-19 rates and 95% confidence intervals for general population non-healthcare workers aged 20 to 69 years old (excluding healthcare workers), for healthcare workers and for some health occupations in Québec, March 1–June 14, 2020. Note. HCW, healthcare worker; public, working for the public health system. Source of denominators to estimate different rates:^{Reference Sahu, Amrithanand, Mathew, Aggarwal, Nayer and Bhoi1}Québec Statistic Institute, population of 2019.²Statistics Canada, 2016 Census (with an added 5% growth of HCW according to other sources).³College of Physicians of Québec, data updated in 2019.⁴Québec Order of Nurses, data updated 2019.^{Reference Schwartz, Achonu and Buchan5}Québec Order of Nurse Assistants, data updated 2019.

Survey participants

Among the 11,223 HCWs who were called, 8,482 (75.6%) were reached: 986 (11.6%) refused to participate, 198 (2.3%) did not meet the inclusion criteria (44 not a HCW, 58 not a COVID-19 case, 14 not English or French speakers, and 82 other reasons), 2,224 (26.2%) agreed to participate but did not complete the online questionnaire and 532 (6.3%) did not work during the exposure period. Thus, 4,542 participants remained for the analysis (Supplementary Fig. 1 online). Based on the information from the provincial database, sociodemographic characteristics, probable source of infection, occupation, and workplace were similar between participant and nonparticipant HCWs (data not shown).

Sociodemographic and work characteristics

Among the 4,542 participants, 92.3% reported the presence of symptoms, 79.2% were female, and the median age was 42 years. For the type of HCW, 35.1% were healthcare support workers (providing basic personal care like cleaning, dressing and feeding patients), 22.6% were nurses, 11.9% were nurse assistants, 6.0% were managers or administrative workers, and 3.1% were physicians (Table 1).

Table 1.

Demographic and Employment Characteristics and Workplace Exposures to COVID-19 by Type of Facility

Note. ACH, acute-care hospital; LTCF, long-term care facility; ICU, intensive care unit; AGMP, aerosol-generating medical procedure.

^a Healthcare workers with exclusive work in acute-care hospitals or long-term care facilities.

^b Other reported facilities: private residences for elderly, community health centers, other residential facilities (care homes and assisted-living facilities), rehabilitation centers, private medical clinics, COVID-19 clinics, ambulances, laboratories, pharmacies, public health department, others.

^c Several types of facilities. For example, if working in several LTCFs, they were classified as LTCF.

^d Test χ² comparing acute-care hospitals versus long-term care facilities statistically significant (P < .05).

^e All facilities where participant works are public.

Among participants, 48.2% worked in LTCFs (45.3% exclusively in LTCFs), 34.2% worked in ACHs (30.5% exclusively in ACHs), 9.5% worked in private residences for elderly, 5.6% worked in public community health centers, 4.8% worked in other residential facilities (care homes and assisted-living facilities), 4.4% worked in rehabilitation centers, 3.1% worked in private medical clinics, and 10.8% worked in other settings. Although 25.6% reported usually working in >1 facility, 10.5% did so during their exposure period, and this rate was twice as high in LTCF workers (8.3%) as it was in ACH workers (4.0%) (Table 1).

In LTCFs, most participants were healthcare support workers (48.2%), followed by nurses (15.8%) and nurse assistants (10.9%). In ACHs, most participants were nurses (37.1%), followed by healthcare support workers (19.3%), and nurse assistants (11.9%) (Table 1). Among the 1,386 HCWs exclusively working in ACHs, 37.5% worked in medical units, 18.3% worked in surgical units, 16.0% worked in emergency departments, 14.4% worked in geriatric departments, and 8.4% worked in intensive care units. Also, 20.6% worked in >1 department.

Secondary household transmission

In the 3,823 households analyzed, COVID-19 symptoms developed in 2,718 (29.8%) of 9,096 other household members, 1,915 (34.5%) of 5,543 adults, and 803 (22.6%) of 3,553 children <18 years old. The secondary attack rate decreased with larger number of household members from 39.9% in households of 2 members to 22.5% if ≥7 members. Overall, 55.8% of households had no secondary cases, 23.0% had all other members becoming sick, and 21.2% had some symptomatic members but not all (Table 2).

Table 2.

Number and Proportions of Households According to the Number of Secondary COVID-19 Cases and Secondary Attack Rate by Household Size

Note. NA, not applicable; CI, confidence interval.

^a The household with 7 secondary cases had 7 persons living with the infected HCW.

Exposure

The workplace was the perceived probable source of infection of 85.4% of participants: 33.7% indicated that their infection was likely transmitted from patients, 9.8% indicated that their infection was likely transmitted from infected coworkers, and 41.9% indicated that they could not determine whether their actual source of infection was patients or coworkers. Other reported sources of infection were household members (3.9%), extended family or other social contacts (0.7%), the community (1.2%), multiple possible sources including the workplace (5.8%), and unknown (2.8%).

Exposure to infected coworkers was reported by 56.9% of participants (Table 1). Exposure to patients with suspected or confirmed COVID-19 was reported by 3,411 (75.1%), of whom 36.7% worked in exclusively dedicated COVID-19 units. Compared with ACHs, HCWs in LTCFs more often had contact with patients and with COVID-19 patients in nonexclusive units (Table 1).

Pandemic preparedness and IPC practices

Overall, 10.9% participants reported having received no IPC training about COVID-19 since February 2020, and 33.6% reported having received only written or posted recommendations. In early spring, no training was reported by 19.0%, and this rate declined to 3.5% in late spring, whereas the percentage who only received written recommendations remained similar (Fig. 3). Absence of training was more frequently reported by healthcare support workers (16.3% vs 8.3% of nurses and 7.5% of all other HCWs; P < .01) and by HCWs working in nonexclusive COVID-19 units (12.6% vs 6.1% for exclusively dedicated COVID-19 units; P < .01). In LTCFs, 13.9% of HCWs had no training, compared with 5.7% in ACHs (P < .01), a difference that persisted in late spring (5.3% vs 1.9%) (Supplementary Fig. 2 and Supplementary Table 1 online).

Fig. 3.

Temporal evolution of the infection prevention and control practices among HCWs infected with COVID-19.

Note. HCW, healthcare worker; PPE, personal protective equipment.

On a self-reported basis, consistent practice of hand hygiene after patient contact was done by 89.4% of participants and slightly improved throughout the study period (P < .01) (Fig. 3). The main reasons for not carrying out hand hygiene were lack of available sink, soap, or hydroalcoholic solution (36.7%); lack of time (35.2%); and forgetting (18.3%) (Fig. 4). Consistent physical distancing during meals increased from 32.6% to 60.8% from early to late spring (P < .01), whereas always wearing a mask when <2 m from coworkers increased from 19.2% to 52.3% during this period (P < .01) (Fig. 3).

Fig. 4.

Reasons for incorrect hand hygiene after patient contact, incorrect PPE use during contacts with COVID-19 patients, and noncompliance with PPE doffing protocol.

Note. PPE, personal protective equipment.

Compared with ACHs, HCWs from LTCFs similarly practiced hand hygiene (88.8% vs 89.3%; P = .75), but they more often kept physical distance (56.3% vs 36.8%; P < .01) or wore masks (56.3% vs 36.8%) during contact with other HCWs (Supplementary Fig. 2 online).

During contacts with non–suspected COVID-19 patients, 29.7% of the 3,699 responders reported not having used any PPE, whereas 66.6% wore a surgical mask and 36.7% used full PPE (ie, mask, ocular protection, gloves, and gown). Full PPE use was more frequent in LTCFs (40.7%) than in ACHs (34.3%; P < .01) (Table 3). Throughout the study period, we detected a significant decrease of HCWs wearing no PPE (P < .01), from 63.7% during early spring to 6.1% in late spring (Fig. 3).

Table 3.

Use of Personal Protective Equipment (PPE) by Type of Exposure to Patients and Type of Facility

Note. ACH, acute-care hospital; AGMP, aerosol-generating medical procedures; LTCF, long-term care facility; PPE, personal protective equipment.

^a AGMP: aerosol-generating medical procedures that include aspiration of tracheal secretions in an intubated or tracheotomized patient, autopsy, bronchoscopy, cardiopulmonary resuscitation, child nasopharyngeal suction, manual ventilation before intubation, nasopharyngeal or oropharyngeal surgery, sputum induction, tracheal intubation or extubation.

^b Frequency of PPE use not reported for contacts with non–COVID-19 patients.

^c 5 participants with no information on the frequency of PPE use.

^d χ² test or Fisher exact test comparing acute-care hospitals with long-term care facilities. Statistical significance at P< .05.

During non–aerosol-generating contacts with COVID-19 patients, almost all (97.7%) of the 3,249 participants reported always using some PPE: 70.5% wore a surgical mask and 6.9% wore a N95 respirator. Full PPE with a surgical mask was consistently used by 59.3% of HCWs, slightly lower in LTCFs than in ACHs (58.1% vs 62.5%; P = .03), but much higher among those working in exclusively dedicated COVID-19 units than in nonexclusive units (73.4% vs 50.8%; P < .01). The proportion of participants in full PPE increased over the study period (P < .01), from 32.5% in early to 79.5% in late spring (Fig. 3). The main reported reasons for not always using the recommended PPE were lack of equipment (54.9%), lack of access to equipment (17.9%), and employers’ instructions (5.6%). Lack of and difficult access to PPE were the main reasons for not wearing PPE throughout the study period, both in ACHs (71.6%) and in LTCFs (76.9%) (Fig. 4).

Aerosol-generating medical procedures were attended by 136 (3.0%) participants, of whom only 35.1% always wore the recommended PPE (ie, N95 respirator, eye protection, gloves and gown) (Table 3). Noncompliance with the doffing protocol after contact with COVID-19 patients was reported by 23.6% of participants (Table 3), a proportion that decreased from 27.7% in early spring to 16.7% in late spring. The following reasons were most frequently reported: absence or difficult access to garbage can or hand hygiene material (33.4%), prolonged use or reuse of PPE items (29.1%), and lack of protocol (17.3% and 31.3% in early spring) (Fig. 4).