title: Dual-subtype vaccine (Fel-O-Vax FIV) protects cats against contact challenge with heterologous subtype B FIV infected cats.
abstract: Fel-O-Vax FIV is a dual-subtype vaccine consisting of inactivated whole viruses of subtype A (Petaluma strain) and subtype D (Shizuoka strain). The efficacy of this vaccine against heterologous subtype A strain challenge was demonstrated, but it is unclear whether the result reflects efficacy in the field. In this study, we evaluated the efficacy of this vaccine against contact challenge by exposing both vaccinated and unvaccinated control animals with cats infected with Aomori-2 strain belonging to subtype B, a subtype prevalent in many regions of the world. Nineteen specific-pathogen-free (SPF) cats were divided into a vaccinated group (six cats), an unvaccinated control group (eight cats), and a challenge group (five cats), and maintained in the same room. Cats were monitored for FIV proviral DNA by nested PCR and for FIV-specific antibody levels by ELISA. After 1 year of commingling, each cat in the vaccinated group was given a booster dose. In addition, the original challenge group was removed and replaced with another challenge group of SPF cats, which were inoculated with the Aomori-2 strain. FIV infection was confirmed in four of the eight animals in the unvaccinated control group by the 29th week in the second year of commingling. In contrast, all of the animals were negative in the vaccinated group. These findings confirmed the efficacy of this vaccine against heterologous stains classified as subtype B, and suggested that the vaccine exhibits broad efficacy against genetically diverse FIV.
authors.affiliation: Department of Veterinary Infectious Disease, School of Veterinary Medicine and Animal Science, Kitasato University, Towada, Aomori 034-8628, Japan.
authors.forename: Hajime
authors.initials: H
authors.lastname: Kusuhara
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Hohdatsu
authors.forename: Mayuko
authors.initials: M
authors.lastname: Okumura
authors.forename: Kayoko
authors.initials: K
authors.lastname: Sato
authors.forename: Yumi
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Kenji
authors.initials: K
authors.lastname: Motokawa
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Gemma
authors.forename: Rie
authors.initials: R
authors.lastname: Watanabe
authors.forename: Chengjin
authors.initials: C
authors.lastname: Huang
authors.forename: Setsuo
authors.initials: S
authors.lastname: Arai
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Koyama
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002415:Cats; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D016181:Feline Acquired Immunodeficiency Syndrome / Q000276:immunology / Q000517:prevention & control* / Q000821:virology; D005260:Female; D016089:Immunodeficiency Virus, Feline / Q000235:genetics / Q000276:immunology*; D008297:Male; D016133:Polymerase Chain Reaction / Q000662:veterinary; D013047:Specific Pathogen-Free Organisms; D014611:Vaccination / Q000662:veterinary*; D022223:Vaccines, Subunit / Q000276:immunology / Q000627:therapeutic use; D014765:Viral Vaccines / Q000276:immunology / Q000627:therapeutic use*
chemical_list: D000914:Antibodies, Viral; D004279:DNA, Viral; D022223:Vaccines, Subunit; D014765:Viral Vaccines