Avian Influenza Research Today is a free monthly online journal that collates and summarizes the latest research about Avian Influenza, including details on bird flu, h5n1, risks, vaccines, prevention.

Rapid diagnosis of H5N1 avian influenza virus infection by newly developed influenza H5 hemagglutinin gene-specific loop-mediated isothermal amplification method.

Imai M, Ninomiya A, Minekawa H, Notomi T, Ishizaki T, Van Tu P, Tien NT, Tashiro M, Odagiri T

Laboratory of Influenza Viruses, Department of Virology 3, National Institute of Infectious Diseases, Gakuen 4-7-1, Musashi-Murayama, Tokyo 208-0011, Japan.

Reverse transcriptase loop-mediated isothermal amplification (RT-LAMP) is a unique gene amplification method that can be completed within 35 min at 62.5 degrees C. In the present study, RT-LAMP was used to develop a rapid and sensitive laboratory diagnostic system for the H5N1 highly pathogenic avian influenza (HPAI). The sensitivity of the system was 0.1-0.01 plaque-forming units per reaction for HPAI-H5N1 viruses belonging to the genetically and antigenically distinct clade 1, represented by A/Vietnam/JP1203/2004, and clade 2, represented by A/Indonesia/JP283/2006. This RT-LAMP sensitivity is 10-fold higher than the sensitivity of standard one-step RT-PCR. By using viral RNAs extracted from avian influenza viruses of H1-H15 hemagglutinin (HA) subtypes and human pathogenic respiratory viruses, it was confirmed that the RT-LAMP system amplifies specifically RNA of the H5 subtype virus. The system detected H5-HA genes in throat swabs collected from humans as well as from wild birds. These results suggest that the present RT-LAMP system is a useful diagnostic tool for surveillance of recent outbreaks of the HPAI-H5N1 virus.

Published 30 March 2007 in J Virol Methods, 141(2): 173-80.
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