Basic estimation-prediction techniques for Covid-19, and a prediction for Stockholm

Tom Britton

We have demonstrated a simple method to estimate and predict an on-going epidemic outbreak both with and without preventive measures put in place. As input data we use the basic reproduction number R 0 and the doubling time during the early stage of the epidemic, and its new doubling time after preventive measures are put in place. The method also uses the reported cumulative number of deaths at a given time Λ(t 1 ), the typical time between infection and death s D , and the infection fatality risk f , in order to time-calibrate the model to calendar time. The method is most sensitive to the doubling times, to some extent also to R 0 , but fortunately less sensitive to the latter quantities which are often equipped with high uncertainty.