Development of duck hepatitis A virus type 3 vaccine and its use to protect ducklings against infections.
A variant type of duck hepatitis A virus (DHAV), DHAV-3 was recently discovered in South Korea and China. Sequence analyses verified that the variant is genetically or serologically different from the DHAV-1 and DHAV-2 types. Duck hepatitis had been reported in South Korea since 1985 and an attenuated DHAV-1 vaccine had efficiently prevented epidemics of DHAV-1 until 2002. Despite the DHAV-1 based vaccine in use the novel DHAV-3 circulating in South Korea remains to be a threat to duckling farming. To develop a live attenuated vaccine against DHAV-3, a representative isolate, AP-04203, was therefore attenuated by repeated passages in SPF chicken embryos 100 times. The 100th passaged virus, AP-04203P100, did not cause clinical sign and mortality in 1-day-old ducklings as well as reversion of virulence capacity. The ducklings vaccinated with AP-04203P100 virus (10(3.0)ELD(50)/0.2ml) on 1-day-old age via the intramuscular injection were well protected from 2 days after challenge with pathogenic AP04203P1 virus via the intramuscular route. In addition, the vaccine candidate also exhibited complete protection against currently circulating pathogenic DHAV-3 isolates. In conclusion, we demonstrate that the live attenuated virus, AP-04203P100, is a promising vaccine candidate facilitating the prevention of duck hepatitis caused by DHAV-3 around East Asia including South Korea.
Kim
Min-Chul
MC
National Veterinary Research and Quarantine Service, Gyeonggi-do, Anyang 420-824, South Korea. mckim00@nvrqs.go.kr
Kim
Min-Jeong
MJ
Kwon
Yong-Kuk
YK
Lindberg
A Michael
AM
Joh
Seong-Joon
SJ
Kwon
Hyuk-Man
HM
Lee
Youn-Jeong
YJ
Kwon
Jun-Hun
JH
D000818:Animals; D002642:Chick Embryo; D004372:Ducks / Q000276:immunology*; D016679:Genome, Viral; D004371:Hepatitis Virus, Duck / Q000235:genetics* / Q000472:pathogenicity; D006524:Hepatitis, Viral, Animal / Q000517:prevention & control*; D010802:Phylogeny; D010850:Picornaviridae Infections / Q000517:prevention & control*; D011201:Poultry Diseases / Q000517:prevention & control; D012367:RNA, Viral / Q000235:genetics; D056910:Republic of Korea; D017423:Sequence Analysis, RNA; D014613:Vaccines, Attenuated / Q000276:immunology; D014765:Viral Vaccines / Q000276:immunology*; D014774:Virulence
D012367:RNA, Viral; D014613:Vaccines, Attenuated; D014765:Viral Vaccines