The first outbreaks of highly pathogenic H5N1 viruses were reported in South East Asia in Guangdong China, since 15 years ago (Tang et al., 1998). Up to date, the virus was reported in more than 60 countries (OIE, 2010). Since then, the disease has become endemic in some Asian and African countries (Poetri et al., 2011). Influenza viruses are members of the family Orthomyxoviridae and are classified as Type A, B and C based on antigenic differences in their nucleoprotein (NP) and matrix (M1) proteins. All avian influenza viruses (AIV) are classified as Type A. Further subtyping is based on antigenicity of the surface glycoproteins viz., haemagglutinin (HA) and neuraminidase (NA). Currently 16 HA and 9 NA subtypes have been identified among influenza A viruses (Fouchier et al., 2005; Palese and Shaw, 2007).