Table 3.

Factors associated with risk of repeat positive test >90 days after initial positive result, with 95% confidence intervals, June–December, 2020, Kentucky, USA

Variable	Repeat positive test		Unadjusted estimates		Adjusted estimates
	Yes(n=593)	No(n=41,054)	RR	95% CI	RR	95% CI
Agea			1.99	1.69-2.34	0.96	0.80–1.16
60+	224 (37.8)	9,510 (23.2)
20–59	369 (62.2)	31,544 (76.8)
Sexb			1.49	1.27–1.76	1.17	0.99–1.39
Female	373 (62.9)	21,781 (53.1)
Male	220 (37.1)	19,273 (46.9)
Month of initial infectionc			2.02	1.72–2.37	1.60	1.36–1.88
March–June	292 (49.2)	13,212 (32.2)
July–August	301 (50.8)	27,842 (67.8)
Symptom statusd			3.43	2.89–4.05	2.31	1.93–2.75
Asymptomatic	196 (33.1)	5,047 (12.3)
Symptoms or unknown	397 (66.9)	36,007 (87.7)
Testing after 90 dayse			2.86	2.44–3.45	1.20	0.99–1.45
≥1 test	239 (40.3)	7,640 (18.6)
No test	354 (59.7)	33,414 (81.4)
LTCFf			6.67	5.56–7.69	4.35	3.45–5.26
Yes	247 (41.7)	3,878 (9.4)
No	346 (58.3)	37,176 (90.6)
Associated with LTCF (n=4,125)	(n=247)	(n=3,878)
Age			1.10	0.86–1.42	0.93	0.72–1.21
60+	153 (61.9)	2,304 (59.4)
20–59	94 (38.1)	1,574 (40.6)
Sex			0.94	0.73–1.24	0.96	0.74–1.26
Female	175 (70.9)	2,798 (72.2)
Male	72 (29.1)	1,080 (27.8)
Month of initial infection			1.32	1.04–1.69	1.36	1.06–1.74
March–June	137 (55.5)	1,866 (48.1)
July–August	110 (44.5)	2,012 (51.9)
Symptom status			1.89	1.48–2.40	1.93	1.51–2.47
Asymptomatic	110 (44.5)	1,120 (28.9)
Symptoms or unknown	137 (55.5)	2,758 (71.1)
Testing after 90 days			0.90	0.69–1.17	0.94	0.72–1.22
≥1 test	172 (69.6)	2,611 (67.3)
No test	75 (30.4)	1,267 (32.7)
Not associated with LTCF (n=37,522)	(n=346)	(37,176)
Age			1.07	0.82–1.38	1.03	0.79–1.33
60+	71 (20.5)	7,206 (19.4)
20–59	275 (79.5)	29,970 (80.6)
Sex			1.28	1.04–1.58	1.32	1.07–1.64
Female	198 (57.2)	18,983 (51.1)
Male	148 (42.8)	18,193 (48.9)
Month of initial infection			1.84	1.49–2.26	1.81	1.46–2.23
March–June	155 (44.8)	11,346 (30.5)
July–August	191 (55.2)	25,830 (69.5)
Symptom status			2.76	2.16–3.50	2.78	2.17–3.52
Asymptomatic	86 (24.9)	3,927 (10.6)
Symptoms or unknown	260 (75.1)	33,249 (89.4)
Testing after 90 days			1.54	1.16–1.96	1.35	1.02–1.75
≥1 test	67 (19.4)	5,029 (13.5)
No test	279 (80.6)	32,147 (86.5)

^aAge: >60 versus 20–59 years of age

^bSex: female versus male; missing data for two individuals with reinfection, 285 individuals without reinfection

^cMonth of initial infection: March–June versus July–August

^dSymptom status: asymptomatic versus symptomatic or unknown during initial infection

^eTesting after 90 days: ≥1 test versus no tests prior to repeat positive