Fig. 1.

SSI index before and during the COVID-19 era. SSI index in the years before the COVID-19 era. Incidence of both superficial and deep SSI is higher than during the COVID-19 era (a, b). In the previous two “COVID-19-free” years (d), we can report only an organ-space SSI significantly increase in 2018 vs. 2019 (see Table 1 fifth and sixth column). *p value: < 0.05