Cat Flu and Vaccinations (Rolph) Flashcards
What are the etiologies of the cat flu?
- Feline Herpes Virus type 1 (FHV-1)**
- Feline Calici Virus (FCV)**
- Other viruses, e.g. FCoV, reovirus
- Bordetella bronchiseptica
- Mycoplasma felis
- Chlamydophila felis
- Pasturella spp.
- Streptococcus equi subsp. zooepidemicus
What’s the significance of cat flu?
- Second leading cause of euthanasia in shelters
- Most common infectious COD in kittens between 1-14 days old (mainly herpes but calicivirus)
What is calicivirus?
Small, single-stranded positive sense RNA virus
- One serotype
- Many different strains (different antigenicity and cross reactivity → important for vaccines)
- High genomic plasticity (virus constantly mutating)
What does calicivirus cause?
- Upper respiratory tract disease
- Oral Vesicular Disease
- Gingivostomatitis
- Limping Syndrome
- Fading Kittens
- Viral Systemic Disease
How is the calicivirus infection spread?
- Aerosolization
- Direct contact
- Fomites (pens, computer keyboards, stethoscopes, etc.)
How long does calicivirus survive in the environment?
8-10 (→ 28) days
- Can survive longer in proper conditions
How many cats are shedding calicivirus?
Evades immune systems (can be long-term)
- 100% at 30 days
- 50% at 75 days
- 25% become ‘carrier cats’
What are clinical signs associated with calicivirus?
- Oral ulceration (typically on tongue margin, take 2-3 weeks to heal)
- Pyrexia
- Excessive salivation
- Sneezing, nasal discharge
- Conjunctivitis
- Coughing (pulmonary lesions rare; focal alveolitis and acute exudative pneumonia → LRT problems)
- Lameness (acute synovitis)
When can acute synovitis be seen?
Joints affected
- Seen from vaccinations because some vaccines have live strains
What is feline herpesvirus?
Double-stranded DNA virus
- Glycoprotein-lipid envelope
- Little strain variation
- Fragile: easily destroyed in environment
What does herpesvirus cause?
- Upper Respiratory Tract Disease
- Conjunctivitis/Keratitis (also ocular lesions)
- Chronic sinusitis
- Glossitis
- Neonatal disease, abortion
- Ulcerative crusting dermatitis
Describe the shedding of Feline Herpesvirus.
Shedding from day 1 for 14 weeks
- Oral, nasal, or conjunctival infection
Where does herpesvirus viral replication take place?
Virus replication and necrosis occurs w/n the nasal turbinates, nasopharynx, and conjunctival mucosa
- Mucous membrane replication → necrosis
How many cats become carriers of herpesvirus?
80% following infection (w/ 45% spontaneously reactivating)
Where is herpesvirus latent?
Latent w/n the trigeminal ganglion
- There until stress, illness, certain drugs, pregnancy, etc. until triggered → quickly show clinical signs
What are the clinical signs of feline herpesvirus?
- Pyrexia
- Sneezing/nasal discharge
- Conjunctivitis (uni- or bi-lateral)
- Uveitis (secondary)
- Cough/dyspnea
- Occasional oral ulceration
- Dermatitis possible (around eyes, nose)
What is Bordetella associated with and what is the percentage of organism isolation?
Organism isolation in 3.5-11% of cats
- Disease associated with rescue facilities, increased numbers of cats in household, and contact w/ infected dogs
What is Bordetella?
Gram-negative coccobacillus
- Affects dogs, pigs, rabbits, cats, humans
- Can act as primary respiratory pathogen or secondary to viral respiratory disease
- Cats can become persistently affected and shed bacteria
How is Bordetella acting as a primary respiratory pathogen or secondary to viral respiratory disease?
Cilia affected (can't beat normally) - Often has concurrent pathogen (hard to tell which appeared first)
How is Bordetella transmitted?
- Direct contact
- Aerosolization
- Fomites
How does Bordetella do in the environment?
Does not survive well in the environment
- Killed by extremes of temperature, pH
What are the clinical signs of Bordetella?
Respiratory disease
- Sneezing
- Pyrexia
- Oculonasal discharge
- Lymphadenopathy
- Coughing (less marked than in dogs)
- Occasionally: cyanosis, dyspnea, death
What is Chlamydophila?
- Obligate intracellular bacteria
- Gram-negative characteristics
- Carrier state
What are the clinical signs of chlamydophilia?
Conjunctivitis (30% of cases)
How do you diagnose chlamydophilia?
- Corneal/oropharangeal/nasal swabs
- PCR
- Intranuclear inclusion bodies
What are some bacterial causes of cat flu?
- Mycoplasma
- Pasteurella
What is mycoplasma and how do you diagnose it?
- Common respiratory pathogen
- Disease association unclear
- Asthma-like signs; may worsen them
- Diagnosis: PCR
What is pasteurella?
- Unknown significance regarding cat flu
- Wide spectrum of antibiotic sensitivity
How do you diagnose cat flu and its various etiologies?
Isolation + culture or PCR
- Plain eye swab: FHV-1 + C. felis PCR
- Plain mouth swab: FHV-1
- Mouth swab in VTM: FCV
- FHV-1: intermittent shedding
- FCV: wild strain/pathogenic?
- Bacteriology: e.g. Bordetella, Mycoplasma
What’s the role of serology with the cat flu and its etiologies?
Limited value as usually vaccinated
- If unvaccinated, only tells if they have antibodies to those organisms (can’t help w/ Herpes)
What’s some nutritional and fluid support for cat flu?
- Warmed food (sardines, tomato sauce, A/D, hot water)
- Esophageal feeding tubes
- ? appetite stimulants (mirtazepine - mild)
- IV/IO fluids
What are some treatments for cat flu?
- Nutritional and fluid support
- Supportive care (cleaning nose, eyes)
- Multivitamins (esp. B vitamins [water-soluble, lose quickly]; anorexia can lead to deficiencies)
- Ocular anti-inflammatory drugs (ocufen, ketorolac)
- Mucolytics/decongestants (can make move to LRT)
- Nebulization (break up mucus)
What is immuno-modulation treatment?
- Interferon therapy (expensive, may be beneficial
- Used w/ calicivirus
What is treatment specific to herpesvirus?
- Famcycovir (low mortality, morbidity)
- L-lysine (helps at high, hurts at low)
What is antibiotic treatment used for regarding cat flu?
Frequent secondary bacterial infections (broad spectrum antibiotics)
- B. bronchoseptica (culture, sensitivity), C. felis, Mycoplasma
What is the antibiotic treatment for cat flu?
- Doxycycline/oxytetracycline (esophagitis, tooth discoloration)
- Fluoroquinolones (retinpathies)
- Azithromycin
How can cattery control help with cat flu?
Address infectious + non-infectious causes
- Decreased stocking density + group size
- Increase air flow
- Sneeze barriers
- Disinfection (1:32 bleach; wash hands, not sanitizer)
- Quarantine (3 weeks)
- Isolation kittening + weaning
- Stop breeding
- Vaccination
How long do maternally derived antibodies protect against FHV-1 last?
2-10 weeks
How long do maternally derived antibodies protect against FCV?
10-14 weeks
When should you vaccinate kittens if maternally derived antibodies are poor?
Before 8 weeks
When should you vaccinate kittens with persistent maternally derived antibodies?
+16 weeks
- Vaccinate later for FCV
What immunity does the cat flu vaccination provide?
No sterilizing immunity
- Only protect against clinical signs (NOT INFECTION)
- No change in FCV prevalence since vaccination (10-40%)
Compare live versus inactivated vaccines.
Live vaccines
- → clinical signs of disease
- Persist in colony w/ potential to mutate → pathogenic
Inactivated vaccines
- May need adjuvant (risk of sarcoma)
- Less effective (especially w/ high maternally-derived antibodies?)
What vaccine type do you use with FPV (Feline Panleukopenia Virus)?
Live vaccine
What vaccine type do you use with FHV-1?
Inactivated
- Gives better levels earlier
What vaccine type do you use with FCV?
Inactivated
- Less seropositive over time but not as effective as modified live
- Safer for patients
What is parvovirus?
CPV2 and FPV (panleukopenia or parvo = same thing)
- Highly contagious (dogs can infect cats)
- Rapidly fatal in puppies, kittens w/o treatment
- Attacks rapidly dividing cells (GI, BM, LN ± myocardium)
When does parvovirus/panleukopenia virus disease occur?
W/n 4-7 days of infection
How long can shedding occur in parvovirus/panleukopenia virus?
Can occur up to 10 days after clinical signs (diarrhea, severe volume depletion)
What is survival like with treatment of parvo/panleukopenia virus?
85-95%
How do you diagnose parvo/panleukopenia virus?
- Assess BM → pancytopenia
- Monitor biochemistry: hypoproteinemia/hypoglycemia, electrolyte abnormalities
- Testing: Antigen/ELISA (use dogs SNAP test on cats too)
What do you do if the Antigen/ELISA tests negative with parvo/panleukopenia virus?
Repeat after 48 hours
- If recently vaccinated, consider confirmatory test (RT-PCR)
How do you treat parvo/panleukopenia virus?
As for Acute Gastroenteritis
- Interferon
- Granulocyte CSF
- Transfusion
- Hyperimmune plasma (plasma from recently well case)
What are the complications that can result from parvo/panleukopenia virus?
- Sepsis (due to BM suppression)
- DIC
- Intussusception
How can an in utero or pre-development of cerebellum panleukopenia infection affect the fetus?
Can result in cerebellar hypoplasia
- → lifelong neurological signs
What are the disadvantages to FCV vaccination?
- Does NOT protect against infection or development of carrier state
- Based on whole viral antigens
- Side effects more common w/ modified life or IN vaccines
What does FCV vaccination depend on?
- Strain used (cross-reactivity, similar to field isolates)
- Monovalent/bivalent
- Modified live/inactivated
- Adjuvanted/non-adjuvanted
Are FPV/FHV-1 and FHV-1/FCV core vaccinations in cats ajd what types are there?
YES!
- Injectable (MLV, non-adjuvanted; Killed, adjuvanted; killed, non-adjuvanted)
- Intranasal (MLV, non-adjuvanted)
What are the kitten vaccine protocols for FPV/FHV-1 and FHV-1/FCV?
Primary kitten series (≤ 16 wks.)
- Begin as early as 6 wks. old, then every 3-4 weeks until 16 weeks old
- Protecting kittens w/ long levels of MDA
What are the adolescent/adult vaccine protocols for FPV/FHV-1 and FHV-1/FCV?
Primary Adult Series (≥ 16 wks.)
- 2 doses, 3-4 weeks apart
What is the booster protocol for FPV/FHV-1 and FHV-1/FCV?
- Single dose given 1 year following the last dose of the initial series (~16 mos. for kittens)
- Then, no more frequently than every 3 years
What are some stipulations to the FPV/FHV-1 and FHV-1/FCV vaccines?
- Killed vaccines preferred for use in pregnant cats (if absolutely necessary), FeLV and/or FIV infected cats (especially those showing evidence of immunosuppression)
- Killed panleukopenia vaccines should be used in kittens < 4 weeks old
- All kittens and cats should receive AT LEAST ONE injectable panleukopenia injection
Is the Bordetella vaccine core or non-core and what are its properties?
Non-core
- Avirulent live, non-adjuvanted
- Intranasal
What is the Bordetella vaccine?
Live-attenuated, IN vaccine
- Can invoke clinical signs
- Fimbrial antigen-based SQ vaccine available in Europe
- Pregnant queens should NOT be vaccinates
What is the primary kitten series for Bordetella vaccine?
Administer a single dose intranasally as early as 8 wks old
What is the primary adolescent/adult series for Bordetella vaccine?
Administer a single dose intranasally
What is the booster protocol for Bordetella vaccine?
Annual booster indicated for cats w/ sustained risk
What are the stipulations regarding the Bordetella vaccine?
- Vaccination may be considered in cases where cats are likely to be at specific risk of infection
- Do NOT give the vaccine parenterally (may cause severe adverse reaction that can be fatal)
What is the Chlamydophila vaccine and its properties?
Vaccine available for ‘at-risk’ (breeding, catteries) cases (non-core)
- Avirulent live, non-adjuvanted
- Killed, adjuvanted
- Injectable
What is the primary kitten series for the Chlamydophila vaccine?
Administer the initial dose as early as 9 wks old
- A second dose is administered 3-4 weeks later
What is the primary adolescent/adult series for the Chlamydophila vaccine?
Administer 2 doses, 3-4 weeks apart
What is the booster protocol for the Chlamydophila vaccine?
Annual booster indicated for cats with sustained exposure risk
What are the stipulations for the Chlamydophila vaccine?
- Vaccination reserved as part of a control regime for cats in multiple-cat environments where infections associated w/ clinical disease have been confirmed
- Inadvertent conjunctival inoculation of vaccine has been reported to cause clinical signs of infection
What is VS-FCV?
Severe systemic hemorrhagic-fever like vascular systemic disease
- Seen in vaccinated cats
- Different strains in all reported cases
What is the incubation period of VS-FCV?
1-5 days
What’s the mortality rate and time to death of VS-FVC?
> 50%
- TTD: 4- days, occasionally more
Are adults or kittens more affected by VS-FCV?
Adults > kittens (may show typical ‘flu’)
- Sentinel, also usually recover
What are some clinical signs of VS-FCV?
- Anorexia, lethargy, depression
- Pyrexia
- SQ edema/ulcerative dermatitis (peripheral vasculitis): nose, lips, pinnae, ~eyes, distal limbs; fluid ooze (>50%)
- Crunchy skin, edematous, swollen
- Mouth ulcers
- Nasal discharge
What is the pathology of VS-FCV?
- Blood: ↓ protein, ↑ total bilirubin, ↑ creatinine kinase
- ↑ Neutrophils, ↓ lymphocytes, non-regenerative anemia, severe coagulopathy
- Peripheral + systemic vasculitis
What presents on necropsy of VS-FCV?
Per clinical signs:
- Severe pancreatitis
- Bronchopneumonia
- Hepatocellular, lymphoid, and splenic necrosis
How do you diagnose VS-FCV?
- Epidemiology (# of in-contact cats w/ clinical signs)
- Isolation + culture (FCV wild strain/pathogenic?)
- All have different genetic sequences
- Serology: limited value as usually vaccinated
- PM exam: immunohistochemistry for FCV
What is the epidemiology of VS-FCV?
- Cat from rescue center immediately before outbreak
- Disease spreads rapidly (practice, shelter, home)
- Crowded, high stress environments (↑ FCV biodiversity)
- Different strains → sequential re-infection
- Persistent infections → progressive evolution
- Multiple infections → viral recombination
(↑ non-neutralizing immunity) - → selects highly contagious + virulent strains
- Same population: matched immune response → little disease
- New population: → VS-FCV
- VS-FCV: ↑ viral pathogenicity + altered cell tropism (invasion of epithelium + endothelium), altered host cytokine response
How do you control a VS-FCV infection?
Infection spreads easily: infected cats
- Asymptomatic carriers, cat handlers, fomites
- Outbreaks have been self-limiting (<100 cats, < 2 mos.)
How is VS-FCV managed?
All suspicious cases:
- Handle w/ strict hygienic + quarantine ideally NOT in vet practice
- Keep in isolation until stopped shedding virus
- Trace all in-contact cats + quarantine all potential cases
How is VS-FCV treated?
- ? High dose interferon, IV fluids, antibiotics, analgesia, corticosteroids?
- ? Oseltamivir (Tamiflu)
What are the details regarding VS-FCV vaccination?
Routine FCV vaccination does not protect F9, 255
- FCV-VSD vaccine?
- Merial Purevax (G1+431) → protection against EU VS-FCV → ↓ clinical scores
- Fort Dodge (2280) → no protection against EU VS-FCV
- Fort Dodge (255 + DD1) → protection against EU + US VS-FCV (67% neutralization US + EU strains)
- BI Calicvax → protection against EU VS-FCV
