DNA Viruses 2 (parvoviruses)

What is the pathogenesis of parvovirus infection?

Replicates in the nuclei of rapidly dividing cells, causing cell destruction and intranuclear inclusion bodies.

Why are parvoviruses difficult to eliminate from the environment?

They are highly stable and resistant to heat, solvents, disinfectants, and pH changes.

How is feline panleukopenia transmitted?

Inhalation or ingestion of virus from contaminated environments.

What is the pathogenesis of feline panleukopenia?

Oropharyngeal and lymph node replication → viremia within 24 hours → infection of intestinal crypts and lymphoid tissues → cell destruction, villous atrophy, and panleukopenia.

Which tissues are targeted by feline panleukopenia virus?

Intestinal crypts, bone marrow, thymus, lymph nodes, and spleen.

What are the clinical signs of feline panleukopenia?

Depression, vomiting, diarrhea, and potentially dehydration and secondary infections.

What can feline panleukopenia cause following transplacental infection?

Fetal death or cerebellar hypoplasia.

What causes death in feline panleukopenia?

Dehydration and secondary infections.

What is the characteristic hematologic finding in feline panleukopenia?

Panleukopenia due to destruction of bone marrow and lymphoid cells.

How is canine parvovirus transmitted?

Ingestion of virus.

What is the pathogenesis of canine parvovirus?

Oropharyngeal and Peyer's patch replication → viremia within 24 hours → infection of intestinal crypts and lymphoid tissues → villous atrophy and immune suppression.

Which tissues are targeted by canine parvovirus?

Intestinal crypts, bone marrow, thymus, lymph nodes, and spleen.

What are the main clinical signs of canine parvovirus?

Depression, vomiting, and bloody diarrhea.

What causes death in canine parvovirus enteritis?

Dehydration and endotoxemia.

What can canine parvovirus cause in infected fetuses or young puppies?

Myocardial necrosis, myocarditis, and heart failure.

Which age group commonly develops acute enteric canine parvovirus disease?

Dogs between weaning and 6 months of age.

What are the major canine parvovirus variants?

CPV-2a, CPV-2b, and CPV-2c.

What is the primary disease syndrome caused by porcine parvovirus?

Reproductive failure, known as SMEDI syndrome.

What does SMEDI stand for?

Stillbirth, mummification, embryonic death, and infertility.

Which pigs are particularly susceptible to porcine parvovirus?

Gilts susceptible to infection during mating and pregnancy.

What is the pathogenesis of porcine parvovirus?

Transplacental infection targets mitotically active fetal cells, causing reproductive failure before fetal immunity develops.

When does transplacental infection occur after porcine parvovirus infection?

Approximately 10–14 days after infection.

What happens when porcine embryos are infected?

Embryonic resorption and infertility.

What happens when porcine fetuses are infected before day 70 of gestation?

Stillbirth or fetal mummification.

What happens when porcine fetuses are infected after day 70 of gestation?

They are generally born alive and healthy because fetal immunity has developed.

How do parvovirus syndromes compare across cats, dogs, and pigs?

Cats: enteritis and panleukopenia; dogs: enteritis, bloody diarrhea, and immune suppression; pigs: reproductive failure and SMEDI.

What are the key similarities between feline and canine parvovirus infections?

Both target rapidly dividing intestinal crypt and lymphoid cells, causing enteric disease and possible fetal death.

What is the major difference between porcine and carnivore parvovirus disease?

Porcine parvovirus primarily causes reproductive failure; feline and canine parvoviruses primarily cause enteric disease.