Isolation and IdentificatiOn Of Very Virulent Infectious Bursal Disease Virus(vvIBDV)Strain NH99
Abstract: An infectious bursal disease virus(IBDV)field strain,named NH99,was isolated and iden— tifed from some flocks with imm une failure in Shanghai according tO the clinical symptom ,pathology, serological test,animal challenge and virus morphology,The virus was characterized as a very virulent infectious bursal disease virus(vvIBDV)through nucleic acid isolation and related DNA sequence analy— sis which have the same molecular characteristics as vvIBDV .This is the first report of outbreak of a— cute infectious bursal disease caused by vvIBDV in Shanghai.