Exploration of local isolate of highly pathogenic avian influenza clade 2.3.2.1 as vaccine candidate to prevent mass outbreak in East Java

Abstract

Highly Pathogenic Avian Influenza (HPAI) H5N1 is a major problem in poultry industry in many countries. It became endemic disease in Indonesia since 2003. Recently, research revealed that current circulate HPAI in Indonesia has switched from clades 2.1 to 2.3.2.1. To eradicate this disease, methods such as stamping out and quarantine seem not suitable applied since poultry industry is one of main sector in agricultural commodity in some areas such as Central Java, Yogyakarta, and East Java. It provides large of job opportunity for native people from rural to city areas. To prevent the morbidity of this disease, vaccination use local seed is primarily needed. This research was conducted to explore local isolate of HPAI clade 2.3.2.1 as vaccine candidate. Samples were obtained from some areas in East Java where outbreak occurred. Molecular characteristic according to Neuraminidase (N) gene was conducted. Samples has close relativity to circulating virus was used as seed vaccine then processed into killed vaccine production. It was challenged to observe the protectivity on poultry. The effectivity of the vaccine was measured through Haemagglutination Inhibition (HI) assay. The result of study showed that isolate DOD_3_2013 has close relativity to circulating virus thus it used as vaccine candidate. Challenged test showed that this vaccine candidate induced higher antibody titer compared to control. The average of antibody titer was 8.2 (log2) with the protection level 100%. It is concluded that this isolate could be used as vaccine candidate to eradicate HPAI clade 2.3.2.1 around East Java.