Trial for Using Emergency Vaccination for Controlling Duck Virus Hepatitis (DVH) Outbreaks in Ducks

This study was conducted to evaluate the use of emergency vaccination to control DVH in ducks. Five liver samples were collected from Pekin ducks showing clinical symptoms of DVH from Kalubia province in summer 2016. The virus was isolated in specific pathogenic free (SPF) embryonated chicken eggs (ECES). The clinical sampleswereexamined by generic RT-PCR followed by partial sequencing of the 3D gene; the results revealed that the isolate was characterized as Duck hepatitis A virus resembling the recent Egyptian virus DHV/Duck/Egypt/AL-Gharbia/2014 belonging to serotype-1 with highest percent identity of (97.9%), and with Duck hepatitis–A virus vaccine with (79.4%) identity . The results obtained from emergency vaccination experiment indicated that emergency vaccination against DVH in young duckling in the experimentally infected and emergently vaccinated group gave good protection against infection with no deaths after emergency vaccination till the end of the experiment (40 days). In contrast, the second group (experimentally infected and not emergently vaccinated) showed deaths reached up to 40% of the ducklings and the lesions in dead and survived ducklings were severe. Therefore, emergency vaccination can be used effectively to face DVH outbreaks as a tool to control the disease.