Prevalence of the SARS-CoV-2 Infection Among Post-Quarantine Healthcare Workers

Figures & data

Figure 1 The follow-up algorithm for a confirmed case of an HCW with COVID-19.

Table 1 Demographic and Clinical Characteristics for the Quarantined Individuals

Parameter	PCR Results of HCW		P-value
	PCR-Negative n = 283 (Respondents = 119)	PCR-Positive n = 18
Age (Mean ± SD)	33.8 Y ± 7.0	32.9 Y ± 8.7	0.90
Range		9 (50%)
20–29	63 (52.9%)	5 (27.8%)
30–39	39 (32.8%)	3 (16.6%)
40–49	13 (10.9%)	1 (5.6%)
50–59	3 (2.5%)	0
60–65	1 (0.8%)
Gender
Males	16 (13.4%)	7 (38.9%)	0.014
Females	103 (86.6%)	11 (61.1%)
Areas of residency (codes)
Zone A	4 (3.4%)	6 (33.3%)
Zone B	5 (4.2%)	5 (27.8%)	0.0001
Zone C	3 (2.5%)	3 (16.6%)
Zone D	15 (12.6%)	1 (5.6%)
Zone E	13 (10.9%)	1 (5.6%)
Zone F	12 (10.1%)	2 (11.1%)
Other zones	67 (56.3%)	0
Job
Nursing (70)	65 (23.0%)	5 (7.1%)
Allied healthcare jobs (108)	105 (37.1%)	3 (2.8%)
Physician (17)	17 (6%)	0	0.58
Trainees (73)	67 (23.7%)	6 (8.2%)
Administrative jobs (33)	29 (10.2%)	4 (9.7%)
Exposure within the 14 days before testing
Worked in a healthcare facility with confirmed cases*	8 (6.7%)	2 (11.1%)	0.62
Contact with a suspected or confirmed case in the community	16 (13.4%)	2 (11.1%)
No clear epidemiological link or exposure source identified	95 (78.8%)	14(77.8%)
Symptoms
Asymptomatic	112 (94.1%)	12 (66.7%)
Symptomatic	7 (5.9%)	6 (33.3%)	0.12
Initial symptoms before testing
Fever	0	0
Dry cough	5 (4.2%)	2 (11.1%)
Shortness of breath	2 (1.7%)	0
Myalgia	0	0
Fatigue	0	0
Gastrointestinal symptoms	0	6 (33.3%)
Headache	0	0
Sore throat	5 (4.2%)	2 (11.1%)
Coryza	2 (1.7%)	1 (5.6%)
Loss of taste and smell	1 (0.8%)	2 (11.1%)
Late symptoms over the course of illness
Fever	0	0
Dry cough	2 (1.7%)	0
Shortness of breath	2 (1.7%)	0
Myalgia	0	0
Fatigue	0	0
Gastrointestinal symptoms	1	0
Headache	0	1 (5.6%)
Sore throat	0	0
Coryza	0	0
Loss of taste and smell	0	0
Chronic diseases
Diabetes mellitus	2 (1.7%)	1 (5.6%)
Hypertension	4 (3.4%)	1 (5.6%)
Sickle cell/other haematological diseases	32 (26.9%)	2 (11.1%)	0.23
Chronic cardiac conditions	4 (3.4%)	0
Other chronic illness	6 (5.0%)	0
Pregnancy in females	5 (4.9%)	0

Notes: *Both HCWs reported close contact with suspected and confirmed COVID-19 cases (uncontrolled source). While the HCWs used a surgical mask, they did not use an N95 mask or eye protection during sample collection (medium risk).

Table 2 N = 301, Positive Cases = 18. Description of the 18 Screened Cases That Tested Positive Through the PCR Screening for COVID-19 Among KFHU’s Staff Living in Qatif

Case Numbers in Chronological Order	Job	Gender	Age (Y)	Area of Residency	COVID-19 Score*	Secondary Cases in KFHU
1	Trainee	F	34	A	8	None
2	Trainee	F	29	A	5	None
3	Nurse	M	26	C	4	None
4	Allied healthcare worker	F	35	B	4	None
5	Allied healthcare worker	F	38	F	3	None
6	Nurse	F	26	A	3	None
7	Nurse	F	25	B	4	None
8	Nurse	M	26	D	3	None
9	Trainee	F	24	A	3	None
10	Trainee	F	23	B	5	None
11	Allied healthcare worker	F	32	A	3	None
12	Nurse	F	37	F	3	None
13	Administrate job	M	53	C	4	None
14	Trainee	M	23	E	3	None
15	Administrate job	M	43	B	3	None
16	Administrate job	M	44	C	4	None
17	Trainee	F	29	B	4	None
18	Administrate job	M	44	A	7	None

Notes: *Score of 4 indicates testing and higher pre-test probability of COVID-19. The KFHU self-assessment tool score would have identified 10/18 (55.6%) cases only.

Figure 2 Viral clearance in days (Kaplan–Meier curve), where the X-axis represents the time in days while the Y-axis shows the percentage of cases still shedding the virus (median = 9 days ± 1.307).