Till date, the pandemic 2009 H1N1 infl uenza virus has spread rapidly and caused a massive burden of disease around the world. It affects the younger population more frequently and can cause severe illness in a small proportion of people. The mortality rate is low and similar to seasonal infl uenza. How the virus will behave in subsequent months in terms of virulence and morbidity is unclear. A better understanding of the disease will help us prepare for the future.