Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Isolation of mixed subtypes of influenza A virus from a bald eagle (Haliaeetus leucocephalus) | Goyal et al. Virology Journal 2010 7 174 http content 7 1 174 VIROLOGY JOURNAL SHORT REPORT Open Access Isolation of mixed subtypes of influenza A virus from a bald eagle Haliaeetus leucocephalus Sagar M Goyal Naresh Jindal Yogesh Chander Muthanan A Ramakrishnan Patrick T Redig Srinand Sreevatsan Abstract From April 2007 to March 2008 cloacal swabs were obtained from 246 casualty raptors recovered by various wildlife rehabilitation centers in the United States. The swabs were placed in a virus transport medium and transported to the laboratory on ice packs. At the laboratory the samples were pooled with each pool consisting of five samples. All pools n 50 were screened for the presence of avian influenza virus AIV using a real time reverse tran-scription-polymerase chain reaction rRT-PCR one of the pools was found positive. All five samples in this pool were tested individually by rRT-PCR one sample from a bald eagle was found positive. This sample was inoculated in embryonated chicken eggs for virus isolation and a hemagglutinating virus was isolated. Complete genome sequencing of the isolate revealed a mixed infection with H1N1 and H2N1 subtypes. Further analysis revealed that the PB1-F2 gene sequence of H1N1 virus had the N66S virulence-associated substitution. Further studies on ecology and epidemiology of AIV in raptors are needed to help understand their role in the maintenance and evolution of AIV. Findings Wild birds are considered natural reservoirs of avian influenza virus AIV and at least 105 species of wild birds have been reported to harbor these viruses 1 . The migratory nature of these bird populations may help disseminate AIV across countries and continents. Most of the wild birds have been reported to harbor low pathogenic avian influenza LPAI viruses 2-5 although highly pathogenic avian influenza HPAI viruses have also been isolated from some species 6 . To understand how AIV is evolving in nature it is important to identify the