Feline Immunodeficiency Virus Flashcards
What family is this in?
Lentivirus
What are characteristics of lentivirus
infected for life, needs reverse transcriptase, has viral provirus.
What are the FIV subtypes?
A-E and putative F. Based on genetic diversity within the envelope, A and B are predominant and are diverse
What are the target cells?
CD4+ cells, dendritic cells, macrophages, CNS cells. Has a long asymptomatic period
What are the numbers of cats infected with FIV?
low prevalence, very small percentage co-infected with FeLV. 12-14% of sick cats are FIV+; average age is 5 years old and mainly got it from biting
What is this virus similar to?
HIV: goes from acute to asymptomatic carriers to AIDS-related complex. Target cells, transmission, and clinical signs are almost all the same
How does this progress?
After a bite, takes 2-6 weeks for the antibodies to increase and for the cat to enter the acute infection or primary viremia stage. Have unspecific clinical signs. After, will be an unsymptomatic carrier or latent phase possibly years later. Have to have strong humoral and CD8+ T cell levels to keep viremia low. CD4+ decreases during latent phase.
What is the final stage of FIV?
Feline Acquired Immune Deficiency Syndrome: is now chronic and recurrent, CD4+ cells decline and the ratio of these to CD8+ decreases. High viral load and opportunistic infections are common.
What are the clinical signs?
Reflect secondary diseases, can see lymphoma, anemia, lymphopenia.
What are the diseases associated with FeLV?
Immunodeficiency and opportunistic: most important and later stages. Can see demodex, cryptococcus, candida, otodectes, etc. Myelosuppression, immune-mediated diseases. Tumors: 5x more likely to develop lymphoma- B cell- or leukemia, with chronic B cell hyperplasia. Neurologic dysfunction: only 5%, strain dependent, can be caused by opportunistic pathogens
What are the differences between FeLV and FIV?
Tumor: FeLV 62x more likely to develop due to direct role of virus and mostly T cell whereas FIV is 5x more likely and has an indirect virus role with primarily B cells. Bone marrow suppression is only common in FeLV, neuro is rare in both, immunodeficiency is common in both. Immune-mediated is rare in FeLV and only sometimes in FIV. Stomatitis is common and very common respectively.
How do you diagnose FIV?
Detect antibodies via ELISA, western blot, IFA. Not target antigen because there is a low viremia, PCR is not as effective as serology (THIS IS A RARE PHENOMENON)
How do you test FIV?
If positive and the cat is less than 6 months old, retest every month or so until it is negative or cats are older than 6 months. If positive and cats are older than 6 months, confirm with another test. If vaccinated or positive in cats with unknown history, do PCR.
What’s important to remember in regards to testing?
Maternal antibodies last for 12-14 weeks in kittens, no test can differentiate between FIv positive and vaccinated so always test before vaccination. Antibodies due to vaccination last for longer than a year.
How do you prevent and control FIV?
Use diluted bleach, test and identify, keep cats indoors, neuter, minimize stress. Vaccine is not core and the one available is killed, limited efficacy since there is so much genetic diversity. Remember not DIVA, only for high risk cats.
