Table 2.

Risk factors for SARS-CoV-2 exposure associated with antibody seropositivity among 2919 Egyptian participants.

	SARS-CoV-2 antibodies				Crude OR (95% CI;LL-UL)	p-value
Risk factors for SARS-CoV-2 exposure	Seronegative (n = 1355)		Seropositive (n = 1564)
	No.	%	No.	%
Practicing COVID-19 protective measures
Not done	385	49.3%	396	50.7%	1.029 (0.656–1.613)	0.902
Partially done	928	45.2%	1126	54.8%	1.213 (0.784–1.877)	0.385
Completely done	42	50.0%	42	50.0%	Ref.
Use of public transportation
No	145	46.9%	164	53.1%	Ref.
Yes	1210	46.4%	1400	53.6%	1.023 (0.808–1.296)	0.851
History of travel abroad within the last six months
No	1343	46.4%	1553	53.6%	Ref.
Yes	12	52.2%	11	47.8%	0.793(0.349–1.802)	0.579
History of COVID-19 infection
Never	1286	50.5%	1260	49.5%	Ref.
Yes	69	18.5%	304	81.5%	4.497 (3.424–5.906)a	0.000
Contact with COVID-19 patient
No	904	49.4%	926	50.6%	Ref.
Yes	451	41.4%	638	58.6%	1.381 (1.187–1.607)a	0.000
Vaccination status against COVID-19
Not vaccinated	1326	48.0%	1434	52.0%	Ref.
Vaccinated	29	18.2%	130	81.8%	4.145(2.753–6.242)a	0.000
Occupational risks (n = 1647)	Seronegative (n = 753)		Seropositive (n = 894)
Occupation
Non-HCWs	483	48.1%	521	51.9%	Ref.
HCWs	270	42.0%	373	58.0%	1.281 (1.049–1.564)a	0.015
Having roommates at work
No	181	52.9%	161	47.1%	Ref.
Yes	572	43.8%	733	56.2%	1.441 (1.135–1.829)a	0.003
Environmental disinfection
No	432	42.9%	575	57.1%	1.339 (1.098–1.634)a	0.004
Yes	321	50.2%	319	49.8%	Ref.
Rooms are well-ventilated
Yes	620	44.0%	790	56.0%	1.629 (1.235–2.150)a	0.001
No	133	56.1%	104	43.9%	Ref.
Use of air conditioner at work
No	617	44.9%	757	55.1%	1.218 (0.939–1.580)	0.137
Yes	136	49.8%	137	50.2%	Ref.
Number of days working online/week
1–3	157	50.5%	154	49.5%	Ref.
4–5	145	44.6%	180	55.4%	1.266 (0.927–1.729)	0.139
6–7	451	44.6%	560	55.4%	1.266 (0.981–1.633)	0.069

^aSignificant results p <0.05. HCWs :Health care workers.