Zhong NS et al. has produced a very comprehensive guideline for the diagnosis and treatment of influenza which can serve Chinese patients who choose to be treated with either Western medicine or traditional Chinese medicine (12). In the former case of antiviral treatment, the adamantanes including the amantadine and rimantadine are not useful for the 2009 pandemic H1N1 virus because of the S31N mutation of the matrix M2 protein. Moreover it has been reported that oseltamivir resistance through the H275Y mutation of the haemagglutinin can emerge in patients without any exposure to oseltamivir as the quasispecies of resistant mutant have the advantage to outgrow sensitive wild type in cell culture (13). It is also important to note that such oseltamivir resistance will result in cross resistance to another neuraminidase inhibitor peramivir. Thus for the treatment of severe cases, other agents such as oro-inhaled or intravenous zanamivir have to be considered. However if the patient has severe pneumonia, inhaled agents will have difficulty of penetrating pulmonary consolidation. The role of sialidase DAS181 is still uncertain. As for polymerase inhibitors such as ribavirin, viramidine and T705, only ribavirin is commercially available but has significant side effects. Though interferons are active in-vitro and in animals, their pro-inflammatory side effects are severe and will not be considered in the clinical setting of severe pneumonia. In fact none of these agents including double-dose oseltamivir has ever been shown to decrease mortality in patients with influenza pneumonia and respiratory failure. Therefore further antiviral targets are being searched such as the nucleozin analogues which aggregate the viral nucleoprotein which is a non-surface and non-enzymatic antiviral target (14). Because elderly patients who have previous exposure to the 1918 pandemic H1N1 virus were relatively protected from the new pandemic 2009 H1N1 virus (15,16), it is conceivable that passive immunotherapy with convalescent plasma or hyperimmune immunoglobulin harvested by plasmapheresis from convalescent patients may be an important treatment option (17,18). Since protective antibody titer is lower after vaccination than natural infection, the convalescent plasma should be collected only from patients with natural infection (19). It is of note that patients with severe disease had a significantly lower serum IgG2 level than those with mild influenza (20). In a case control study, patients with severe influenza pneumonia have a lower mortality, serial viral load and proinflammatory serum cytokine level if treated with convalescent plasma (21). Further randomized control trials should be performed on patients with severe influenza pneumonia to ascertain the role of different treatment options.