Table 1.

Effect of formaldehyde and glutaraldehyde inactivation of SARS-CoV

Virus	Dilution	Day 1			Day 2			Day 3
		4 °C	25 °C	37 °C	4 °C	25 °C	37 °C	4 °C	25 °C	37 °C
Formaldehyde treatment
No	1:1000	xa	x	x	x	x	x	x	x	x
Yes	1:1000	x	x	x	x	x	x	x	x	x
Yes	1:4000	4.45 ± 0.25b	1.31 ± 0.29	1.31 ±0.29	4.02 ± 0.38	1.31 ± 0.29	1.5 ± 0	3.28 ± 0.14	1.14 ± 0.29	1.14 ± 0.29
Glutaraldehyde treatment
No	1:1000	≤1.0c	≤1.0	≤1.0	≤1.0	≤1.0	≤1.0	≤1.0	≤1.0	≤1.0
Yes	1:1000	≤1.0	≤1.0	≤1.0	≤1.0	≤1.0	≤1.0	≤1.0	≤1.0	≤1.0
Yes	1:4000	2.70 ± 0	1.31 ± 0.29	≤1.0	2.26 ± 0.38	≤1.0	≤1.0	2.19 ± 0.25	≤1.0	≤1.0
Yes	No	5.28 ± 0.29	5.09 ± 0.58	4.03 ± 0.14	5.03 ± 0.14	4.86 ± 0.29	3.36 ± 0.29	5.12 ± 0.14	4.1 ± 0.52	2.78 ± 0.14

^aFormaldehyde treatment fixed the cells in the TCID₅₀ assay so virus could not be detected.

^bGeometric mean of triplicate samples ± S.D.

^cThe limit of detection for the TCID₅₀ assay is ≤1.0.