%0 Journal Article %T Outbreak of pandemic influenza A/H1N1 2009 in Nepal %A Bal Ram Adhikari %A Geeta Shakya %A Bishnu Upadhyay %A Khagendra Prakash KC %A Sirjana Shrestha %A Guna Dhungana %J Virology Journal %D 2011 %I BioMed Central %R 10.1186/1743-422x-8-133 %X Out of 609 collected samples, 302 (49.6%) were Universal Influenza A positive. Among the influenza A positive samples, 172(28.3%) were positive for Pandemic influenza A/H1N1 and 130 (21.3%) were Seasonal influenza A. Most of the pandemic cases (53%) were found among young people with ¡Ü 20 years. Case Fatality Ratio for Pandemic influenza A/H1N1 in Nepal was 1.74%. Upon Molecular characterization, all the isolated pandemic influenza A/H1N1 2009 virus found in Nepal were antigenically and genetically related to the novel influenza A/CALIFORNIA/07/2009-LIKE (H1N1)v type.The Pandemic 2009 influenza virus found in Nepal were antigenically and genetically related to the novel A/CALIFORNIA/07/2009-LIKE (H1N1)v type.The 2009 flu pandemic is a global outbreak of a new strain of H1N1 influenza virus, often referred to as swine flu [1]. The virus is a novel strain of influenza [2]. This new pandemic H1N1 influenza strain contained genes from five different flu viruses: North American swine influenza, North American avian influenza, human influenza, and two swine influenza viruses typically found in Asia and Europe [3]. Due to the genetic mutations in its hemagglutinin (HA) protein, the influenza viruses can escape from the host defense mechanisms and thus to be able to continuously infect human and other species [4,5].On June 11, 2009, the ongoing outbreak of Influenza A/H1N1 was officially declared by the WHO to be the first influenza pandemic of the 21st century with new strain of Influenza A virus subtype H1N1 identified in April 2009 [6]. Till May 30, 2010 worldwide update by World Health Organization (WHO) more than 214 countries have reported laboratory confirmed cases of pandemic influenza H1N1 2009, including over 1,8,114 deaths [7].Nepal has started screening febrile travelers with respiratory symptoms from affected countries for the Pandemic influenza A (H1N1) since April 27, 2009, and the first case was detected on June 21, 2009 and introduction of the disease to th %U http://www.virologyj.com/content/8/1/133