Successive waves in pandemic infections: physical diffusion theory and data comparisons

We establish the principal that the prediction, timing and magnitude of second and more distinct waves of infection can be based on the well - known physics and assumptions of classical diffusion theory. This model is fundamentally different from the commonly used SEIR and R0 fitting methods. Driven by data, we seek a working approximation for the observed orders of magnitude for the timing and rate of second and more waves. The dynamic results and characteristics are compared to the data and enable predictions of timescales and maximum expected rates where diffusive effects dominate.The important point is this simple physical model allows understanding of the dominant processes, provides prediction estimates, and is based the solutions derived from existing, consistent and well-known physical principles. The medical system and health policy implications of such inexorable diffusive spread are that any NPI and other countermeasures deployed for and after the rapid first peak must recognize that large residual infection waves will then likely occur.