title: Reactivation of latent bovine herpesvirus 1 in cattle seronegative to glycoproteins gB and gE.
abstract: Six heifers were vaccinated intranasally with the live bovine herpesvirus 1 (BHV1) temperature-sensitive (ts) vaccine strain RBL106 within 3 weeks of birth. These calves most likely still had maternal antibodies against BHV1. Thereafter, these heifers were vaccinated several times with an experimental BHV1 glycoprotein-D (gD) subunit vaccine. At the age of 3 years these 6 heifers were seronegative in the BHV1 gB and gE blocking ELISAs, but had neutralizing antibodies against BHV1, probably induced by the vaccinations with the gD subunit vaccine. Five of these 6 heifers excreted BHV1 after treatment with dexamethasone. Restriction enzyme analysis of the genome of the excreted viruses revealed that all 5 isolates had a BHV1.1 genotype and that isolates of 3 heifers were not obviously different from the ts-vaccine strain. The restriction enzyme fragment pattern of the isolate of 1 heifer was clearly different from the pattern of the ts-vaccine strain. It is concluded that cattle can be seronegative against BHV1 gB and gE but can still carry BHV1 in a latent form. This finding strongly suggests that there are completely BHV1 seronegative cattle that are latently infected with BHV1. The impact of this finding on BHV1 eradication programmes is discussed.
authors.affiliation: Animal Health Service in The Netherlands, Drachten, Netherlands.
authors.forename: J J
authors.initials: JJ
authors.lastname: Hage
authors.forename: R D
authors.initials: RD
authors.lastname: Glas
authors.forename: H H
authors.initials: HH
authors.lastname: Westra
authors.forename: M A
authors.initials: MA
authors.lastname: Maris-Veldhuis
authors.forename: J T
authors.initials: JT
authors.lastname: Van Oirschot
authors.forename: F A
authors.initials: FA
authors.lastname: Rijsewijk
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D000917:Antibody Formation; D000918:Antibody Specificity; D002417:Cattle; D002418:Cattle Diseases; D004279:DNA, Viral / Q000032:analysis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006566:Herpesviridae Infections / Q000276:immunology / Q000662:veterinary* / Q000821:virology; D007242:Herpesvirus 1, Bovine / Q000254:growth & development / Q000302:isolation & purification / Q000502:physiology*; D007112:Immunity, Maternally-Acquired; D016133:Polymerase Chain Reaction; D014759:Viral Envelope Proteins / Q000276:immunology*; D014764:Viral Proteins; D014765:Viral Vaccines; D014775:Virus Activation; D017735:Virus Latency
chemical_list: D000914:Antibodies, Viral; D004279:DNA, Viral; D014759:Viral Envelope Proteins; D014764:Viral Proteins; D014765:Viral Vaccines; C046998:bovine herpesvirus type-1 glycoproteins