Fig. 1.

Standard Gibbs energy of binding of SARS-CoV and SARS-CoV-2 variants, as a function of time. Data for SARS-CoV variants are with blue triangles (▲), while the blue dotted line (·····) is a linear fit through the SARS-CoV data. MERS-CoV is represented by the green square (■). The SARS-CoV-2 variants are represented with orange circles (●), while the dashed orange line (—————) represents a linear fit through the SARS-CoV-2 data. Each data point is labelled with the name of the variant. Between the SARS-CoV epidemic, MERS-CoV epidemic and SARS-CoV-2 pandemic, time has passed, which was not presented in the graph for better clarity.