- Since 1997, global healthcare leaders are cautiously awaiting the emergence of a new influenza pandemic. It seems that thus far, the current H1N1 pandemic is not the realization of the fears of a worst case 1918-like scenario, as may have been the case should this have been an H5N1 highly pathogenic avian influenza HPAI-borne outbreak. Six months into the outbreak, we are still awaiting informed answers on too many issues regarding some of the most basic characteristics of this new disease. One such issue of continuous debate is the severity and actual case fatality rates in this pandemic, as compared with seasonal influenza. Estimates vary widely for both seasonal influenza and for the new pandemic, and the marked differences in the age case-mix of the patients further add to the complexity of this debate. As many of the dilemmas currently deliberated by senior healthcare decision-makers are directly impacted by these estimates, many decisions have thus far been taken in a state of considerable uncertainty. In this article the authors briefly discuss this uncertainty and its impact on decisions taken so far, as well as on decisions still to be taken. In the coming weeks we will publish in this journal a set of articles that will summarize the data and insights gained thus far about the new pandemic and the Israeli mitigation efforts to date.