Cross Protectivity of Yolk Immunoglobulin Anti-Hemagglutinin Protein of High Pathogenic Avian Influenza A subtypes H5N1 Administered on Chicken Infected by High Pathogenic Avian Influenza A subtypes H5N1

Yolk Immunoglobulin (IgY) against Avian Influenza (AI) is commonly used as immunotherapy and immunodiagnostic techniques. Application of IgY mixed in drinking water is known effective to inhibit AI replication. The effectivity of IgY anti-Hemagglutinin Protein (anti-HA) of High Pathogenic Avian Influenza (HPAI) clade 2.1 (A/Chicken/Blitar/2003) was tested against infection of High Pathogenic Avian Influenza clade 2.3.2 (A/Duck/Sidoarjo/2012). The inhibiting activity was observed through Immunohistochemistry. Sixty chickens were infected with 105 EID50/ml of HPAI clade 2.3.2 (A/Duck/Sidoarjo/2012). Yolk Immunoglobulin with different amounts (0 μg, 100 μg, 200 μg and 400 μg) were administered at three different times which were 24 hours before infection, at the time of infection, and 24 hours after infection. The observation was conducted for 7 days. During post infection observation, death chickens were managed for immunohistochemistry assay to observe the present of virion and IgY sialic acid 2,3-alfa galactosa (SA α 2,3 gal) blocking activity in septa alveoli. By the end of observation all chickens were euthanized for immunohistochemistry assay. The result showed that anti-HA IgY obtained from HPAI clade 2.1 could protecting infection of HPAI clade 2.3.2. According to immunohistochemistry assay, the administration of IgY can neutralize the infecting virus marked by the number of virions observed in septa alveoli of the lungs. Regarding the assay, the dose of 200 μg and 400 μg of IgY applied 24 hours before the infection, can reduce clinical signs and mortality of infected chicken (80-100%). The best dose of the IgY to protect them from infection of clade 2.3.2 (A/Duck/Sidoarjo/2012) was 400 μg administered 24 hours before infection. It could be concluded that administration of IgY anti-Haemaglutinin Protein (anti-HA) of High Pathogenic Avian Influenza (HPAI) clade 2.1 (A/Chicken/Blitar/2003) could protect chickens against the infection of HPAI clade 2.3.2 (A/Duck/Sidoarjo/2012), even though they belong different clades. The protection rate was 80-100%. Further research should be done to discover the cross-protectivity of IgY as preventive method against HPAI outbreak.