OBJECTIVES: Outbreaking of COVID19 is now attracting heated interests worldwide. This study proposes the prediction method for the ‘signal’, which foresees the date of the outbreak. Based on the Chinese evidence, the study predicts the peak dates of the numbers of cases and deaths.

METHODS: The study used the data until 3^rd April sourced from the European Centre for Disease Prevention and Control (ECDC). First of all, this study predicts the signal date. The signal date was calculated as follows. Assumed Xt as the cases of a particular day, Xt-1: the previous day, Xt-2: two days before. Given Xt, Xt-1, Xt-2 are more than 100, the ratio is defined as (Xt + Xt-1) / Xt-2). When the ratio has remained less than 3.0 for three consecutive days, the final day is defined as the ‘signal’ date. The peak occurs within around 14 days from the signal date. Thereafter, the numbers of patients will continue to decrease, and the decrease rates depend on the characters of regions.

RESULTS:The peak days of several countries including hardest-hit ones were calculated. In the case of Italy, the signal and the peak dates were calculated as March 8th and March 22nd, respectively. As for the other countries, Spain (3/18,4/1), France(3/15,3/29), Germany(3/24,4/7), UK(3/23,4/6), USA(3/24,4/7),etc. The number of cases and deaths were also predicted based on the several cases: the Chinese evidence vs the other types of cases.

CONCLUSIONS:The numbers of cases and deaths vary on the countries. This difference may be due to national strategies. Several miracles were found on this pandemic (Asian miracles: Taiwan, Korea, Japan). Germany and Korea have a small number of deaths in spite of a large number of cases, and Taiwan has succeeded in taking measures at the border. Predicting method for the peak date and the future numbers could help introduce the appropriate measures.