Feline Retroviruses Flashcards
what does feline leukemia virus do with DNA?
copies- provirus- are inserted randomly into host genome
what are the FeLV major protein groups?
gag
pol
env
what is important about gag protein p27 of FeLV?
abundant in cytoplasm and plasma of infected cats
used for most diagnostic tests
what are almost all cats with FeLV originally infected by?
FeLV-A
why is prevalence of FeLV decreasing?
vaccination
testing/separation
which FeLV subgroup increases the frequency of neoplasia in a cat?
FeLV-B
how is the virus shed from viremic cats?
constantly: same amount whether they are sick or healthy
what happens about 3 weeks after infection in progressive infection?
bone marrow starts producing infected neutrophils and platelets
can a regressive infection convert into a progressive state with FeLV?
yes- pregnancy, immunosuppression
what disease conditions are associated with FeLV infection?
bone marrow disorders
neoplasia
immunosuppression
immune-mediated disease
what are FeLV bone marrow disorders associated with?
progressive infection
how much more likely are FeLV cats with progressive infection to develop lymphoma than cats without FeLV?
60x
what is one of the main causes of death in FeLV cats?
infection secondary to immunosuppression
what are the FeLV associated immune mediated diseases?
glomerulonephritis
uveitis
polyarthritis
when should you test for FeLV?
kitten
sick
about to be adopted/rehomed
at risk of eexposure
“unknown” status
what is the most common screening test for FeLV?
ELISA
what does the ELISA for FeLV detect?
viral antigens: gap protein p27 in plasma
what does it mean that the IFA for FeLV is highly specific?
positive result is highly reliable
what can be used to test for regressive FeLV infection?
provirus PCR
what are the FeLV alternative therapies?
lymphocyte T cell immune modulator
AZT: reverse transcriptase inhibitor
feline interferon omega
what are the FeLV vaccine options?
inactivated adjuvanted FeLV vaccine
nonadjuvanted recombinant FeLV vaccine
what is FIV?
enveloped RNA virus
family retroviridae
genus lentivirus
what does FIV do?
infects CD4+ helper T cells and macrophages and destroys them
decreased cell-mediated immunity
who is at highest risk for FIV?
intact adult male outdoor cats
how is FIV transmitted?
primary: bite wounds (shed in saliva)
blood transfusions
vertical transmission not likely
what is FIV pathogenesis characterized by?
long period of clinical latency
what type of virus is feline leukemia virus?
enveloped RNA
retroviridae of gammareetrovirus
how does feline leukemia virus infect cells?
reverse transcribes RNA into DNA in cells
cell divides resulting in daughter cells with provirus
what is the env protein gp70 of feline leukemia virus used for?
vaccine
what do FeLV test kits detect?
all 4 subgroups of FeLV
what does FeLV-C cause?
erythroid hypoplasia and therefore severe anemia
how is FeLV transmitted?
vertical: embryonic death, stillbirth, viremic kittens fading
horizonta
what are the three outcomes of FeLV pathogenesis?
progressive: 30-40%
regressive: 30-40%
abortive: 20-30%
what is the most common neoplasia associated with FeLV infection?
thymic lymphoma
what do bone marrow disorders associated with FeLV look like?
anemia: pure red cell aplasia
leukopenia
thrombocytopenia
is the ELISA for FeLV more likely to have false negatives or false positives?
false positives
negative result is highly reliable
what types of infection can a cat have with a positive FeLV PCR?
regressive
progressive
not abortive
what should you avoid giving cats with FeLV?
glucocorticoids or immunosuppressants
what does the FeLV vaccine prevent?
progressive infection
not regressive infection
who is most susceptible to FeLV?
kittens
is FeLV or FIV more contagious?
FeLV
also higher morbidity
where does FIV replicate first?
lymphocytes and macrophages
what are the three phases of FIV?
acute
subclinical
terminal
how long can cats remain subclinical for FIV?
several years, maybe entire lives
subclinical phase: T cell numbers rebound
what is terminal FIV like?
neoplastic
opportunistic infections
myelosuppression
neurologic disease
what are the FIV disease syndromes?
severe stomatitis
neurologic signs
uveitis
chronic diarrhea
what is the ELISA for FIV used to detect?
antibodies ro p24 core protein and sometimes to the gp40 transmembrane protein
can serologic tests distinguish between maternal antibodies or vaccine for FIV and FIV infection?
yes: anigen FIV/FeLV and witness FeLV-FIV
how can you treat FIV?
steroids?
reverse transcriptase inhibitor
feline interferon omega
lymphocyte T cell immune modulator
does the lifespan of FIV infected cats differ from those not infected?
not really
if a cat tests positive for FIV on the ELISA, what should you do?
confirm with western blot
retest in 6 months
