Distribution of outbreak events reported in our corpus, classified by outbreak-affected country. This figure represents the outbreak affected countries reported in news articles in our corpus. The map illustration was created by using Google Maps API  for the visualized purpose of location distribution. The chart in the top-left corner of the figure shows the number of documents that report the situation in each country. Note that, in our corpus, although most of the articles reported the outbreak within one country, there are also some documents that reported the outbreak situations in many countries.