Feline Immunodeficiency Virus: characteristics and role in pathology

Abstract

The review describes structure and biology feline immunodeficiency virus, epidemiology, clinical manifistation, immunological and immunogenetic characteristics of the pathogenesis, principles of diagnosis, treatment and prophylactic. This is a brief overview of the current state of knowledge of this virus. The feline immunodefficiency virus (FIV) is a retrovirus of the Lentivirus genus (Family Retroviridae) was initially isolated from colony of domestic cats in California (USA) in 1986 and has now been recognized as a common feline pathogen worldwide. FIV closely related to HIV, which infect members of Felidae family and it is an importmant viral pathogen worldwide in the domestic cats. FIV these reasons has been studied widely as both an important veterinary pathogen and an animal model for HIV/AIDS. However, it is important to emphasise that humans are not susceptible to FIV infection. The main cellular target for FIV is the CD4+ T cell. FIV causes an immune system disease in domestic cats involving depletion of the CD4+ population of T lymphocytes, increased susceptibility to opportunistic infections, and sometimes death. Seven genetically distinct subtypes has been defined (A,B,C,D,E,F,U-Nzenv).The seroprevalence of feline immunodeficiency virus infection of cats varies markedly between geographic regions. Transmission of FIV is principally by parenteral inoculation of the virus in blood and saliva, presuamably via biting during fighting. Most clinical signs are not directly caused by FIV, clinical signs will be the result of a secondary infection. The virus itself is responsible for immunodeficiency or immune stimulation. Chronic gingivostomatitis one of the most common presenting signs in FIV-infected cats. Methods of diagnosis are included virus isolation (not used routinely), polymerase chain reaction with sensitive and specificities ranging from 40-100%. These techniques result in relatively high numbers of false-positive and false-negative results. Routinely, FIV-infection is diagnosed by detecting antibodies using ELISA and immunochro-matography methods. Western blot analysis is considered the "gold standart" for FIV serology to confirm questionable results. The most common drugs used for treatment of FIV-infection: reverse transcriptase inhibitors drugs, that ingibit firal ensymes, such as DNA or RNA polymerases, integrase ingibitors, protease ingibitors; and interferons. Development of an effective vaccine against FIV is difficult because of the high number and variations of the virus strains. Vaccines that only protect against a single virus variant, have already demonstrated a good efficacy against homologous FIV strains. This review summaries pertinent findings about FIV from work published in a variety research journals.