Table 2.

Ct values of SARS-CoV-2 RNA extracted from heat treated virus.

Heat-treatment		Virus concentration
		7.0 × 104 (pfu/mL)		7.0 × 102 (pfu/mL)		7.0 (pfu/mL)
Temperature (°C)	Time minutes)	Ct Value
		(± St dev)	Difference from unheated	(±St dev)	Difference from unheated	(±St dev)	Difference from unheated
Untreated	0	17.2 (±0.1)	0	23.2 (±0.1)	0	30.2 (±0.3)	0
56	60	18.6 (±0.1)	+1.4	24.3 (±0.1)	+1.1	30.5 (±0.2)	+0.3
80	15	18.1 (±0.1)	+0.9	24.8 (±0.1)	+1.6	28.8 (±4.9)	−1.4
80	30	21.0 (±0.1)	+3.8	28.5 (±0.4)	+5.3	34.7	+4.5
80	60	28.1 (±0.5)	+10.9	37.5*	+14.3	U	N/A
80	90	25.8 (±0.3)	+8.6	35.4 (±0.4)	+12.2	U	N/A
95	1	18.8 (±0.3)	+1.6	26.6 (±0.8)	+3.4	32.5 (±0.4)	+2.3
95	5	21.7 (±0.2)	+4.5	29.4 (±0.6)	+6.2	36.2	+6

Each Ct value is the mean from duplicate RNA extractions.

^*Only one sample gave a Ct value. U = Ct undetermined (RNA not detected); N/A = Not applicable.