Fig 2. Passaging of hCoV-19/Turkey/ERAGEM-001/2020 in Vero E6 cells led to an increase in the viral titer.

The viral supernatant was collected at 48 h post-infection in each passage and tested by a focus forming assay (FFA) for titration of the virus at the 2nd to the 4th passages. Fluorescent foci in each well were counted, and the virus titers were calculated and expressed as fluorescent focus units per ml (FFU/ml). A Mann-Whitney U test was performed for comparisons between different passage numbers of virus where p<0.05 considered significant, *p<0.05. The error bar represents ± the standard deviation.