Fig. 2

Preservation of viral infectivity in samples varies with VTM sterilization method and is affected by storage temperature and starting dose. VTM sterilized by filtration, autoclave or irradiation was inoculated at a level of a 1.2 × 10⁴ TCID₅₀/mL or b 1.2 × 10²TCID₅₀/mL SARS-Cov-2, and then incubated at indicated temperatures for up to 72 h. Shown are mean ± SEM for 5–7 data points, pooled from two independent experiments. Dashed lines represent the final concentration of virus used to inoculate the VTM. Two-way ANOVA with Tukey’s post-tests was used to compare all groups at each time point; * indicates any group that showed a p value less than 0.05 compared to the filtered group, * p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001