TABLE 3: Emergency department healthcare workers classified according to history of COVID-19 and IgG positivity status (antibody level ≥ 1 COI and antibody level < 1 COI).

	IgG antibody negative (<1.00 COI )	IgG antibody positive (≥1.00 COI)	P value
	(n=50)	(n=174)
History of nCoV (−) CoronaVac (−) % (n)	76.3 (29)	23.7 (9)
History of nCoV-19 (+) CoronaVac (−) % (n)	4.8 (2)	95.2 (40)	<0.001
History of nCoV-19 (−) CoronaVac (1 dose) % (n)	80.0 (8)	20.0 (2)
History of nCoV-19 (−) CoronaVac (2 doses) % (n)	9.7 (10)	90.3 (93)
History of nCoV-19 (+) CoronaVac (2 doses) % (n)	3.2 (1)	96.8 (30)