The 2009 flu outbreak in humans, known as H1N1 influenza A, refers to influenza A due to a new H1N1 strain called swine-origin influenza virus A. The signs and symptoms of novel influenza A (H1N1) virus infection are similar to those of seasonal influenza, and specific diagnostic testing is required to distinguish novel influenza A (H1N1) virus from seasonal influenza virus. It results in various degrees of infection, ranging from mild to severe to fatal. For the treatment of swine-origin influenza virus A oseltamivir and zanamivir are effective in most cases. Influenza A (H1N1) pneumonia in the newborn has not been yet reported in the literature. To our knowledge, this is the first report of a neonate of pneumonia in which influenza A (H1N1) virus was isolated. © 2010 Wiley-Liss, Inc.