Development and application of an improved infectivity assay for the standardization of avian encephalomyelitis vaccines

• Published in: Vaccine Vol. 8; no. 3; p. 283
• Main Authors: Shafren, D R, Tannock, G A
• Format: Journal Article
• Language: English
• Published: Netherlands 01-06-1990
• Subjects: Animals; Antigens, Viral - analysis; Biological Assay; Brain - immunology; Chick Embryo; Encephalomyelitis Virus, Avian - immunology; Enterovirus - immunology; Enterovirus Infections - prevention & control; Enzyme-Linked Immunosorbent Assay; Viral Vaccines - analysis; Viral Vaccines - standards
• ISSN: 0264-410X
• DOI: 10.1016/0264-410X(90)90059-U

An improved infectivity assay for avian encephalomyelitis viruses (AEVs) is described in which susceptible 7-day-old chicken embryos were inoculated with dilutions of a particular AEV strain and, after incubation for 12 days, the presence of viral antigen in brains was detected by an enzyme-linked immunosorbent assay (ELISA). The assay (the brain antigen ELISA), which may be used for the titration of both egg-adapted and non-egg-adapted strains, can be completed within 12 days. For the conventional essays of non-egg-adapted vaccine strains, embryos are infected in ovo and hatched chickens examined for neurological signs after 3-4 weeks. No animal handling facilities are required with the brain antigen ELISA and results of comparable sensitivity to the hatch-out assay were obtained.