Theory and Parameterization of Infections and Waves by Covid-19: A 6-Countries Data Analysis

From data of USA, Japan, Germany, UK, Italy and Russian, it is claimed that the Global pandemic dictated by the dynamics of Corona virus exhibits distributions that would correspond to a morphology of Bessel-like type. Under the assumption that the pandemic contains phases of infection denoted by the velocity and acceleration of propagation of virus, then a model of polynomials given by the integer-order Bessel functions is proposed. These polynomials enter in a statistical approach to define the law of infections as function of time for the ongoing global pandemic. From this, the data evolution and their different behaviors are interpreted in terms of the different phases including the Delta variant for the recent months until August 2021.

Predictive Theory of Covid-19 infections at European countries through Bessel functions: Past and present

The data of infections by Covid-19 is modeled through the integer-order Bessel functions that have been parametrized in according to the morphology of data. In particular, the modeling is focused on official data belonging to UK, Germany, Italy and Netherlands. The free parameters of model have been coherently linked to data. Interestingly, it was seen that a”silent period” with the lowest cases of infections play a relevant role for new pandemics as well as the apparition of new strains, such as the most recent”delta-variant”. © 2021 IEEE.

Modeling the Waves of Covid-19.

The challenges with modeling the spread of Covid-19 are its power-type growth during the middle stages of the waves with the exponents depending on time, and that the saturation of the waves is mainly due to the protective measures and other restriction mechanisms working in the same direction. The two-phase solution we propose for modeling the total number of detected cases of Covid-19 describes the actual curves for many its waves and in many countries almost with the accuracy of physics laws. Bessel functions play the key role in our approach. The differential equations we obtain are of universal type and can be used in behavioral psychology, invasion ecology (transient processes), etc. The initial transmission rate and the intensity of the restriction mechanisms are the key parameters. This theory provides a convincing explanation of the surprising uniformity of the Covid-19 waves in many places, and can be used for forecasting the epidemic spread. For instance, the early projections for the 3rd wave in the USA appeared sufficiently exact. The Delta-waves (2021) in India, South Africa, UK, and the Netherlands are discussed at the end.

Momentum managing epidemic spread and Bessel functions.

Starting with the power law for the total number of detected infections, we propose differential equations describing the effect of momentum epidemic management. Our 2-phase formula matches very well the curves of the total numbers of the Covid-19 infection in many countries; the first phase is described by Bessel functions. It provides projections for the saturation, assuming that the management is steady. We discuss Austria, Brazil, Germany, Japan, India, Israel, Italy, the Netherlands, Sweden, Switzerland, UK, and the USA, including some analysis of the second waves.