Possibilities of exponential or Sigmoid growth of Covid19 data in different states of India

SUPRIYA MONDAL; Sabyasachi Ghosh

According to present data, highest number of +ve cases has been noticed in Maharashtra (MH). We noticed in MH-panel of Fig. (1) , that last slope parameter is λ = 0.16, which was previously λ = 0.43. This larger to lower exponential transformation is definitely a good signal for MH but further extension of last exponential growth is so dangerous that it can cover full population of MH within the end of June, 2020. In the upper left panel of Fig. (2) , the pink dotted line represent that exponential growth, where number of population (NoP) in MH is marked by red arrow. However, proper interventions like lock-down, maintaining self precautions can transform the exponential to Sigmoid-type profile. Considering two guess values N max = 10 4 , 10 5 , where total cases might be saturated due to undertaking interventions, we can get two Sigmoid functions S 1 and S 2 respectively, shown by blue dash and black solid lines. Time derivative of exponential function and Sigmoid functions will give corresponding new case predictions, which is shown in lower left panel of Fig. (2) with same line styles as considered in upper panel for total case plots. New case data of MH is also included. They are quite fluctuating but matched roughly with low t range of exponential and Sigmoid functions. For predicted hopeful functions S 1 and S 2 , the turning of new cases from increasing to decreasing trend has to be seen around end of April and mid of May. Number of Beds (NoB) in Govt. hospitals in different states are documented in the Ref. [9] . For MH, this number is shown by green dash line in left upper and lower panels of Fig. (2) .