Parvoviridae - Feline panleukopenia (FPV)

Question 1

What are the common names for Feline Parvo?

Answer 1

Feline panleukopenia
Feline distemper
Feline infectious enteritis

Question 2

Who are the hosts for FPV?

Answer 2

Wild and domestic felines, raccoon, mink

Highly infectious– severe in kittens

Question 3

T/F Virtually all cats are exposed and infected within their first year of life.

Answer 3

True

Question 4

How long are unvaccinated kittens that acquire maternal antibodies protected for?

Answer 4

3 months

75% of unvaccinated healthy cats have demonstrable antibody titers by 1 year of age.

Question 5

How is the virus spread?

Answer 5

Urine or feces for 6 weeks after recovery

However, FPV is maintained in populations through environmental persistence.

Question 6

If an owner loses a kitten to FPV, what should you recommend before bringing a new kitten home?

Answer 6

Do not introduce a new kitten to the household without having it vaccinated.

Question 7

How are felines infected?

Answer 7

Oso-nasally by exposure to infected animals, feces, secretions, contaminated fomites, in-utero transmission to kittens, mechanical transmission by flies

Question 8

If a pregnant cat is infected, what happens to the fetus’ at early, mid, and late gestation?

Answer 8

Early- Fetal death and resorption
Mid- Abort mummified fetuses
Late - CNS damage, cerebellar hypoplasia

Question 9

What is the pathogenesis of FPV?

Answer 9

1) Entry in oropharynx
2) Initial virus replication in pharyngeal lymphoid tissue
3) Viremia to other organs and tissues via blood stream
4) Cells in the “S phase” of actively replicating are infected and killed – prevented from entering mitosis

Question 10

What is the “hallmark” of FPV?

Answer 10

Leukopenia– destruction of all WBCs - Lymphocytes, neutrophils, monocytes, and platelets.
The more severe, the worse the prognosis

Question 11

What other cells are destroyed by FPV?

Answer 11

Cells present in circulation (thrombocytopenia)

Cells in lymphoid organs

Question 12

How does FPV cause enteritis?

Answer 12

1) Virus damages replicating cells deep in the crypts of the intestinal mucosa – Crypt stem cells, panted cells
2) Epithelial cells are normally lost in the GI tract but there are no replacements since the virus killed the “stem cells”.

Question 13

What are the results of the enteritis caused by FPV?

Answer 13

Malabsorption
Diarrhea
Shortening of intestinal villi

Question 14

What parts of the CNS are damaged by FPV in neonates?

Answer 14

Optic nerve and retina
Cerebellar hypoplasia (when fetus is infected in last 2 weeks of pregnancy or first 2 weeks of life)

Question 15

What causes cerebellar hypoplasia?

Answer 15

Lysis of mitotic cells of the external germinal layer

Question 16

How does disseminated intravascular coagulation occur as a result of FPV in kittens?

Answer 16

1. Gram negative is a common sequelae of systemic FPV infection.
2. Endotoxin (LPS) induces expression of tissue factor III on endothelial cells.
3. Tissue factor III is a potent activator of coagulation, resulting in DIC, followed by hemorrhages.

Question 17

What age group of kittens are most commonly infected by FPV?

Answer 17

3-5 months of age

Question 18

What are the clinical signs of FPV?

Answer 18

Fever, depression, anorexia, rough coat, vomiting, bloody diarrhea, severe dehydration, hypothermia, sudden death from DIC/dehydration.
Cerebellar hypoplasia
Retinal degeneration in infected kittens

Question 19

Should queens be vaccinated with a MLV when pregnant?

Answer 19

No! They may show infertility or abortion of dead or mummified fetuses.

Question 20

How is FPV diagnosed?

Answer 20

History and Clinical Signs
Hematology:
Leukopenia, neutropenia -- <2000 cells/uL = poor prognosis
Virus isolation
PCR
Serology

Question 21

How is FPV treated?

Answer 21

Fluid therapy and withholding food prevent vomiting and slow down mitotic activity of cells.
Broad spectrum antibiotics to prevent secondary bacterial infection.

Question 22

How is FPV controlled?

Answer 22

Strict hygiene
Quarantine of incoming cats
Disinfection with bleach for 10 minutes

Question 23

What types of vaccines are available for FPV?

Answer 23

MLV

Inactivated vaccines

Question 24

Who should the MLV not be administered to?

Answer 24

Pregnant cats
Immunosuppressed cats
Kittens <4 weeks old

Question 25

What is the vaccination schedule for FPV?

Answer 25

1. 1st vaccination at 6-9 weeks
2. Two or Three doses every 3-4 weeks afterwards.
3. The last does should not be given before 16 weeks to make sure that maternal antibodies are not interfering.