Generic probabilistic modelling and non-homogeneity issues for the UK epidemic of COVID-19

Anatoly Zhigljavsky; Jack Noonan

The reproductive number R 0 is the main parameter defining the speed of development of an epidemic. There is no true value for R 0 as it varies in different parts of the UK (and the world). In particular, in rural areas one would expect a considerably lower value of R 0 than in London. Authors of [3] suggest R 0 = 2.2 and R 0 = 2.4 as typical; the authors of [6] use values for R 0 in the range [2.25, 2.75]. We shall use the value R 0 = 2.5 as typical which may be a slightly pessimistic choice overall but could be an adequate choice for the mega-cities where the epidemics develop faster and may lead to more causalities. In rural areas, in small towns, and everywhere else where social contacts are less intense, the epidemic is milder.