Lecture 15 3/26/24 Flashcards
What are the characteristics of feline resp. disease complex?
-includes feline rhinotracheitis/feline herpesvirus 1 and feline calicivirus
-often complicated by secondary infections
-transmitted by fomites and aerosols
What are the clinical signs of feline resp. disease complex?
-fever
-tearing
-rhinitis
-salivation
-depression
-anorexia
-ocular signs (FHV specific)
-oral signs (calicivirus specific)
How is FRDC diagnosed?
-clinical signs
-scrapes or staining of conjunctiva
-PCR
Which antiviral is typically used against FRDC?
famciclovir (off-label)
Which vaccine covers both FHV and calicivirus?
FVRCP vx
What are the characteristics of feline coronavirus?
-tropism for GI and/or resp. systems
-development of FIP leads to multi-system involvement
-threat to both domestic and non-domestic felines
-leading cause of death younger than 2 years old
What are the characteristics of FCoV serotype 1?
-unique feline strains
-most prevalent
-receptor unknown
What are the characteristics of FCoV serotype 2?
-recombination of FCoV type 1 with canine coronavirus
-receptor is aminopeptidase-N found in intestinal brush border cells
How do the different FCoV serotypes play into infection?
-the two types can simultaneously infect a host
-both types have been found in inapparent, persistent, and FIP-associated infections
What are the risk factors for FCoV, based on host, environment, and agent?
host:
-genetics
-early weaning
-overcrowding
-concurrent infections
-stress
environment:
-overcrowding
-shared litter boxes
-inflammatory diet
agent:
-severity of exposure
-virulence and mutability
-serotype
What are the characteristics of FCoV transmission/life cycle?
-transmitted fecal-oral
-replicates in small int. epithelial cells
-can shed in feces, saliva, urine
-carrier status possible
-stress increases viral shedding load
What is the pathophysiology that converts FCoV to FIP?
-FCoV enters GI tracts and makes its way to Peyer’s patch macrophages
-virus mutates and acquires virulence factors that allow for macrophage infection and replication within them
-leads to rapid dissemination of macrophages from Peyer’s patches throughout the lymphatics
-type III hypersensitivities can occur, such as antigen/antibody complexes
-increased vascular permeability and circulating inflammatory cells can lead to fluid buildup in abdominal cav.
What are the clinical signs of FCoV?
initial infection:
-can be subclinical
-mild/severe diarrhea
-mild resp. symptoms
enteritis stage:
-severe acute or chronic vomiting
-diarrhea +/- weight loss
-incontinence
FIP:
-multisystemic inflammatory vasculitis
What are the clinical signs of effusive FIP?
-abdominal distension +/- thoracic effusion
-muffled heart sounds
-pyrexia
-weight loss
-dyspnea/tachypnea
-pale or icteric MMs
-abdominal masses
What are the clinical signs of non-effusive FIP?
-mild pyrexia
-anorexia
-dull/depressed
-ocular changes
-neurologic abnormalities
-dyspnea
-icterus
-abnormal abdominal palpation
How can FCoV/FIP be diagnosed?
-PCR
-bloodwork/serum chem values
-liver values
-histology
-effusion analysis
-antibody titers
What are the characteristics of FIP treatment?
-no treatment to prevent FCoV becoming FIP
-no approved drugs for FIP in US; supportive care only
-FIP often fatal; QOL major factor
-nucleoside analog currently used for treatment in China
What are the characteristics of FCoV/FIP management/control?
-FIP has no cat-to-cat transmission, only FCoV
-wait 2 months before new cat introductions
-disinfect surfaces regularly
-minimize # of cats in household
-vaccine available, but not recommended
What are the characteristics of feline panleukopenia virus?
-highly contagious
-stable and ubiquitous
-transmitted via fomites, direct contact, fecal-oral, or in utero
-cannot be inactivated with alcohol
What is the pathogenesis of feline panleuk. systemic infection?
-intranasal or oral infection or oropharynx and lymphoid tissues
-viremia and dissemination
-lymphoid depletion and thymic involution
-GI replication in intestinal crypts leads to blunted villi
-decreased absorption, increased permeability
What is the pathogenesis of feline panleuk. in utero?
-early: fetal death, infertility, abortion, mummified fetuses
-late/neonatal: cerebellar hypoplasia
What are the clinical signs of feline panleuk.?
-fever
-depression
-vomiting
-diarrhea
-dehydration
-thickened intestinal loops
-mesentery lymphadenopathy
-cerebellar hypoplasia signs
How can feline panleuk. be diagnosed?
-clinical signs
-blood work
-serology
-ELISA (not common due to reactivity with MLV vx)
-PCR
How is feline panleuk. treated?
-supportive care
-isolation from other cats
How is feline panleuk. prevented?
-vaccination
-decontamination of environment
What are the characteristics of panleuk. immunity?
-shedding can occur following vx that may “immunize” other cats
-thought that infection leads to life-long immunity
What are the characteristics of FeLV?
-exogenous retrovirus
-replicates in bone marrow, salivary glands, resp. epithelium
-not zoonotic
What are the characteristics of FeLV subtypes?
-FeLV-A: cat-to-cat transmission
-FeLV-A + proto-oncogenes = feline sarcoma virus
-FeLV-B, -C, and -T: mutated forms of FeLV-A
What are the characteristics of feline sarcoma virus?
-endogenous retrovirus
-viral-induced sarcoma + FeLV leads to fibrosarcoma
-FeLV recombines with cat’s cellular DNA to transduce a proto-oncogene already present from previous FSV infection
-different from feline injection site sarcoma
What are the characteristics of FeLV transmission?
-can be horizontal or vertical
-exposure routes include oral/nasal, saliva, transplacental, milk, urine, feces, blood, fomites
What is the early pathophysiology of FeLV?
-oropharyngeal lymphoid tissue is infected
-monocytes and lymphocytes travel to distant tissues; primary viremia
-infection gets to bone marrow and establishes in leukocytes and platelet progenitors
What are the characteristics of an abortive FeLV outcome?
-primary viremia
-immune response is sufficient to eliminate infection
-diagnostics with be neg. for viral RNA, proviral DNA, and antigen
-diagnostics will be pos. for antibodies
What are the characteristics of a regressive FeLV outcome?
-initially antigen pos. on ELISA and PCR, but neg. by IFA
-no shedding
-high neutralizing Ab titer
-when reactivation occurs will see proviral replication and weak PCR pos.
What are the characteristics of a progressive FeLV outcome?
-poor immune response to infection
-initially antigen pos. on ELISA and PCR, but neg. by IFA
-all antigen and PCR tests become pos. as infection progresses
-low/undetectable neutralizing antibodies
-shortest survival
Which animals are at greatest risk for FeLV?
young kittens
What are the clinical signs of FeLV?
-anorexia/weight loss
-poor coat
-enlarged LNs
-fever
-gingivitis/stomatitis/pale gums that is not cured by extractions
-anemia
-skin/bladder/URT infections
-diarrhea
-seizures/behavior changes/neuro disorders
-abortion
-neoplasia
When should FeLV testing be done in different animals?
-kittens: prior to initial vx series
-adults: prior to vx series
-previously outdoor cats: prior to introductions to other cats
-any animals with recurrent infections or suspicious clinical signs
What are the characteristics of FeLV treatment and prevention?
-treatment geared towards managing immune-compromised status and symptoms
-prevention best done through vx and keeping cats indoors
What are the characteristics of FIV?
-causes dysregulation of CD4+/CD8+ T cell ratio
-can occur as a co-infection with FeLV
-horizontal transmission most common (saliva), vertical transmission possible
What is the pathogenesis of FIV?
-initially targets CD4+ T cells and monocytes/macrophages
-over time, tropism changes and virus begins infecting B cells and CD8+ T cells
-has acute, asymptomatic, and clinical phases
What are the characteristics of the FIV acute phase?
-CD4/8 decline in first few weeks
-immune response leads to antibody production, increase in CD8 T cells, and decrease in antigen levels
-can see transient fever, lymphadenomegaly, lymphopenia
-pos. for both antibodies and antigens
-1-3 months
What are the characteristics of the FIV asymptomatic phase?
-subclinical
-months to years
-may never progress
-pos. for antibodies, neg. for antigens
What are the characteristics of the FIV clinical phase?
-decline of both CD4 and CD8 T cells
-predisposition to secondary infections and neoplasia
-can see oral stomatitis, gingivitis, colitis, recurrent infections, parasitic infections, and fungal infections
-pos. for antibodies and antigens
What are the diagnostic options for FIV?
-ELISA for antibody
-PCR for nucleic acid
-western blot for antibody
How many days after infection does it take for FIV antibodies to be detected?
60 days
What are the characteristics of FIV treatment and control?
-no cure, only supportive care
-no vx; keep cats indoor or outdoor restricted
