At the time of writing (mid-May), the early experience with H1N1 (swine derived) influenza A virus has not lived up to the initial predictions of widespread morbidity and mortality, with most infections being self-limited. However, this novel influenza virus may eventually cause infection in up to a third of the earth’s population. With a case fatality rate around 0.4 percent, it will likely contribute to the death of millions of people worldwide (1).