Survival and immunization of raccoons after exposure to pseudorabies (Aujeszky's disease) virus gene-deleted vaccines.
In a controlled experiment, 16 wild-trapped raccoons were exposed to 1 of 2 genetically modified live pseudorabies virus (PRV) vaccines used in swine. One vaccine had genes deleted for thymidine kinase (TK(-)) and glycoprotein G (gG(-)); the other had an additional deletion for glycoprotein E (gE(-)). These vaccines were administered orally and intranasally at four dose levels: 10(3), 10(4), 10(5), and 10(6) TCID(50). The 21 days survival rate was 37.5% for the gG(-)TK(-) vaccine; all of the survivors developed antibodies to PRV. All animals receiving the gG(-)gE(-)TK(-) vaccine survived; 75% (all except the lowest dose) developed anti-PRV antibodies. Survivors were challenged intranasally with a 3.2x10(3) TCID(50) dose of the virulent wildtype PRV Shope strain. Two of the remaining three gG(-)TK(-) vaccinated raccoons survived the challenge; for the gG(-)gE(-)TK(-) vaccine, the survival rate was 50% (4/8). The raccoons with higher vaccine-induced antibody titers were more likely to survive the challenge with the virulent PRV; there was a 100% mortality rate for raccoons lacking detectable anti-PRV antibodies. This experiment indicates that exposure of raccoons to modified live gene-deleted PRV vaccines may result in an immune response, and that this immunity provides some protection against exposure to virulent virus.
Weigel
Ronald M
RM
Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Illinois, 2001 South Lincoln Avenue, Urbana, IL 61802, USA. weigel@uiuc.edu
Hahn
Edwin C
EC
Scherba
Gail
G
D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D001921:Brain / Q000821:virology; D004279:DNA, Viral / Q000097:blood; D011558:Herpesvirus 1, Suid / Q000235:genetics / Q000276:immunology*; D007114:Immunization / Q000662:veterinary*; D009500:Neutralization Tests; D014066:Palatine Tonsil / Q000821:virology; D016133:Polymerase Chain Reaction / Q000662:veterinary; D011557:Pseudorabies / Q000276:immunology* / Q000821:virology; D022421:Pseudorabies Vaccines / Q000276:immunology*; D011821:Raccoons / Q000276:immunology / Q000821:virology*; D016019:Survival Analysis; D013937:Thymidine Kinase / Q000276:immunology; D012668:Trigeminal Ganglion / Q000821:virology; D014613:Vaccines, Attenuated / Q000276:immunology / Q000592:standards; D014759:Viral Envelope Proteins / Q000276:immunology
D000914:Antibodies, Viral; D004279:DNA, Viral; D022421:Pseudorabies Vaccines; D014613:Vaccines, Attenuated; D014759:Viral Envelope Proteins; C089580:glycoprotein E, Suid herpesvirus 1; C042966:pseudorabies virus glycoproteins; D013937:Thymidine Kinase