Influenza Virus: Mutational Variants in H5N1 and H1N1

Three major types of influenza virus viz. influenza virus A, influenza virus B and influenza virus C have been reported on the basis of internal antigen (matrix protein which remains bound to ribonucleoprotein of the genome). Influenza virus A was found to have pandemic potential. The 16 H and 9 N subtypes of it were determined on the basis of surface antigens (hemagglutinin and neuraminidase). The H5N1 genome was found to have eight segments of ribonucleoprotein of ssRNA. Each segment codes different protein. A major problem is faced in vaccine development against surface antigens because the virus has very rapid mutation rate. The PB2 gene of segment 1 seems to give an insight to develop a peptide based vaccine for the treatment of bird flu because of a significant mutation at 627 position which has changed the Lys (K) of H1N1 to Glu (E) in H5N1 i.e. K627E mutation.