DNA-viruses

Parvoviridae

Taxonomy

  • Realm: Riboviria (RNA viruses)

  • Phylum: Negarnaviricota (negative-sense RNA)

  • Subphylum: Polyploviricotina

  • Class: Insthoviricetes (from influenza, Isavirus, Thogotovirus)

  • Order: Ortervirales (reverse of retro)

  • Family: Parvoviridae

Subfamilies and Genera

  • Subfamilies:

    • Parvovirinae - viruses of vertebrates

    • Densovirinae - viruses of insects and invertebrates

  • Genera: 8 genera including:

    • Amdoparvovirus

    • Aveparvovirus

    • Bocaparvovirus

    • Copiparvovirus

    • Dependoparvovirus

    • Erythroparvovirus

    • Protoparvovirus

    • Tetraparvovirus

Members of Genera

  • Protoparvovirus:

    • Feline Panleukopenia Virus

    • Mink Enteritis Virus

    • Canine Parvovirus 2

    • Porcine Parvovirus

    • Parvoviruses of Rodents

    • Rabbit Parvovirus

  • Amdoparvovirus:

    • Aleutian Mink Disease Virus

  • Aveparvovirus:

    • Chicken and Turkey Parvoviruses

  • Bocaparvovirus:

    • Bovine Parvovirus

    • Canine Minute Virus

  • Dependovirus:

    • Goose Parvovirus

    • Duck Parvovirus

  • Erythroparvovirus:

    • Parvoviruses of Nonhuman Primates

Virion Properties

  • Small, non-enveloped, 25 nm in diameter

  • Icosahedral symmetry

  • Single-stranded negative sense linear DNA

  • Length: 4.5 kb to 5.5 kb

  • Stability to environmental conditions including heat and pH

Viral Replication

  • Receptor: Transferrin for canine parvovirus and feline panleukopenia virus

  • Depends on cellular replication during mitotic S phase

  • Binding to sialic acid for hemagglutination

  • DNA replication and capsid assembly occur in the nucleus, requiring host-cell functions

  • Pathogenesis is determined by the need for cycling cells for virus replication

Effects on Developing Organisms

  • Infection during organogenesis can lead to widespread tissue destruction

  • Feline Panleukopenia selectively destroys cerebellum in feline fetuses; Canine parvovirus affects myocardium in pups

  • Older animals are less susceptible but continuously dividing cells can be infected

Lifecycle of Parvovirus (B19V Example)

  1. Attachment

  2. Penetration (endocytosis)

  3. Uncoating

  4. DNA replication

  5. RNA transcription

  6. Protein translation

  7. Assembly of virions

  8. Cell lysis

Diseases Caused By Parvoviridae

  • Feline Panleukopenia Virus: Generalized disease in kittens, causing panleukopenia, enteritis, and cerebellar hypoplasia.

  • Canine Parvovirus: Subtypes cause enteritis, myocarditis (rare), lymphopenia.

  • Porcine Parvovirus: Leads to stillbirth and mummification.

  • Mink Enteritis Virus: Causes leukopenia and enteritis.

  • Aleutian Mink Disease Virus: Chronic immune complex disease and encephalopathy.

  • Mouse Parvoviruses: Persistent infection or fetal malformations.

  • Goose Parvovirus: Causes hepatitis, myocarditis.

  • Duck Parvovirus: Similar pathologies as Goose.

  • Chicken and Turkey Parvoviruses: Enteritis.

Additional Characteristics of Parvoviridae

  • Highly resistant to cleaning and disinfection, complicating sterilization efforts due to environmentalgoose