Table 3.

Negative T-SPOT results for COVID-19.

	Control (%)	HD (%)	p Value
2–6 M	66.7 *	43.1 §	0.02
3–3 W	35.0 †	29.0 ¶	0.66
3–3 M	37.2 ‡	24.2 ‖	0.19

2–6 M: 6 months after the primary series. 3–3 W: 3 weeks after the booster dose. 3–3 M: 3 months after the booster dose. COVID-19: coronavirus disease 2019. HD: Hemodialysis. * n = 45; ^† n = 40; ^‡ n = 43; ^§ n = 65; ^¶ n = 63; ^‖ n = 62. The correlations between the T-SPOT results and antibody titers of each of the three measurement points in each group were evaluated (Figure 4). No significant correlations were observed at 6 months after the primary series, 3 weeks after the booster dose, or 3 months after the booster dose.