Curr Infect Dis Rep (2012) 14:275–283 many cases was underestimated by commonly used pneu- monia severity scores. Given the limited sensitivity of RIDT and immunofluorescence assays, confirmation of pandemic H1N1 influenza A infection can only be made by rRT-PCR or viral culture. Although annual immunization is the most important preventive measure, NI are the agents of choice for chemoprophylaxis in selected high risk patients, and for treatment. Treatment with NI beyond 48 h of symptoms should be considered only for patients with severe disease. Disclosure No potential conflicts of interest relevant to this article were reported. Open Access This article is distributed under the terms of the Crea- tive Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited. References Papers of particular interest, published recently, have been highlighted as: Of importance, Of major importance 1. 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