Abstract: The results of analyzing the relationship between large-scale epidemics (pandemics) caused by the Ebola, influenza AH1N1, and AH7N9 viruses and the MERS-CoV coronavirus with global solar factors for the period from 2008 to 2019 (24th cycle of solar activity) are presented. A variable change in the annual values of pandemic cases has been established, corresponding to the regular course of F10.7 cm (r ~ 0.65), MF (r ~ 0.85) and λ315 nm (r ~ 0.83) in the 24th SA cycle. It was concluded that the dynamics of the spread of pandemics depend on temporary changes in UVB radiation power, in particular, at the boundary of the spectral bactericidal efficiency curve (λ315 nm). © 2025 Elsevier B.V., All rights reserved.