“…In many recent studies , mathematical epidemiological modelling is used to predominantly develop mass-action models and suitable tools for analyzing COVID-19 dynamics [5] , [6] , [7] , [8] , [9] , [10] , [11] , [12] , [13] , [14] . Different mathematical models are used for this purpose as the transmission rates and virus behaviour depend on individuals' precautionary measures, daily vaccination rates, and vaccination efficiencies [15] , [16] , [17] , [18] , [19] , [20] , [21] . In [5] , [6] , a complete analysis of the actual number of deaths due to COVID-19 was studied by the authors using a new class of probability density functions and the exponentiated transformation of the Gumbel type-II distribution.…”