Eradicability of infectious bovine rhinotracheitis (IBR) /infectious pustular vulvovaginitis (IPV) virus infection. 2. Studies of the virus latency of Riems IBR/IPV vaccine (live viral vaccine) virus strain and field virus following infection of immunized animals
Kretzschmar, C.
Archiv für Experimentelle Veterinarmedizin 37(6): 829-835
1983
ISSN/ISBN: 0003-9055 PMID: 6322718 Document Number: 206541
The virus strain of Riems IBR/IPV live virus vaccine differed from field virus strains, in that it obviously did not stay latent in the organism following intranasal and intramuscular immunization. Field virus adhered to the nasal mucous membrane and multiplied in immunized animals in spite of the presence of serum neutralizing antibodies. Adequate protection against intranasally applied field virus doses between 104 and 105 KID50 was not obtainable until antibody titres of 1:32 or more were reached, which proved to be possible only by revaccination. Field virus infection left immunized animals with virus latency, just as it did with non-immunized, fully susceptible animals. Hence, field virus cannot be eradicated from a given herd unless the highest possible amount of immunity has been built up. [For Part 1 see VB 52, 2295].