Prediction of the time evolution of the COVID-19 disease in Guadeloupe with a stochastic evolutionary model

MERIEM ALLALI; PATRICK PORTECOP; MICHEL CARLES; DOMINIQUE GIBERT

This equation shows that, if β is the only information available, the pairs of parameters [R 0 , T I ] cannot be determined uniquely unless additional information is available through the knowledge of either R 0 or T I . Information about T I can be obtained by recognising that this period of time corresponds to the duration of the smooth curved segment that separates the two linear segments discussed above. In curve N I , the curved segment starts at day 40 when the change of R 0 occurs. However, because new infectious patients do not immediately contaminate others but instead do that during the period of time T I , an abrupt change of R 0 appears smoothed. Consequently, this is only after day 50, that a linear segment corresponding to the new value of R 0 appears in the N I curve. This phenomena is of a considerable practical importance because it represents a latency (or an inertia) of the control measures taken by the authorities to reduce and extinct the epidemic process. Such a latency has to be clearly explained to the population in order to encourage people to maintain they efforts to remain in containment.