When on June 11th WHO announced that the Influenza A (H1N1) was a pandemic, the first pandemic declared since1968, it took nobody by surprise. In fact the US government had already acted as if the pandemic had been announced. A careful strategy was mapped to explain that even though the level of the epidemic was raised to the highest, grade 6, this did not indicate that the flu had become more severe. However, this discussion around the Influenza A (H1N1) flu revealed that the set of tools to describe a potential pandemic was limited. There are at least three important elements that need to be assessed.