What is the Difference Between Poxvirus and Parvovirus

The main difference between poxvirus and parvovirus is that poxvirus is the largest DNA virus whereas parvovirus is the smallest DNA virus.

Poxvirus and parvovirus are two types of DNA viruses. Both are disease-causing viruses affecting both animals and humans. 

Key Areas Covered

1. What is Poxvirus
   • Definition, Characteristics, Importance
2. What is Parvovirus
   • Definition, Characteristics, Importance
3. Similarities Between Poxvirus and Parvovirus
   • Outline of Common Features
4. Difference Between Poxvirus and Parvovirus
   • Comparison of Key Differences

Key Terms

Parvovirus, Poxvirus

What is Poxvirus

Poxvirus is a brick-shaped or oval-shaped virus with large double-stranded DNA in the genome. It causes diseases in humans and other animals. Generally, the common symptoms of poxviral infection include the formation of lesions, skin nodules, or disseminated rash. In addition, poxvirus spread due to contact with infected animals, people, and materials. Some poxviruses such as the smallpox virus no longer occur in nature. But other poxviruses still cause diseases like monkeypox virus, orf virus, and molluscum contagiosum.

Figure 1: Poxvirus

Furthermore, poxvirus is the largest form of virus and it contains linear, double-stranded DNA in the genome.  The size of the poxvirus genome is large: 86 kb in size. Apart from that, poxvirus contains multiple membranes surrounding the core. In general, the diseases of poxvirus spread through droplets or fomites. Poxvirus infection affects internal organs, lungs, and the skin.

What is Parvovirus

Parvovirus is a non-enveloped, icosahedral-shaped virus with an 18 to 26 nm diameter. It contains single-stranded DNA. Generally, the replication of the virus occurs in the nucleus of the dividing cells. The single-stranded DNA genome forms a double-stranded intermediate of positive and negative single-stranded DNA packaged separately in the viral genome. The parvoviral genome contains only two genes: genes for the replication of the initiator protein and the protein of the viral capsid.

Figure 2: Parvovirus

Moreover, the disease of parvovirus is transmitted through the respiratory route. Generally, viral replication occurs in the erythroid precursor cells in the bone marrow, causing erythroid aplasia. The parvovirus infects many species of animals.

Similarities Between Poxvirus and Parvovirus

• Poxvirus and parvovirus are two types of DNA viruses.
• Moreover, both are disease-causing viruses.

Difference Between Poxvirus and Parvovirus

Definition

Poxvirus refers to any of a group of large DNA viruses that cause smallpox and similar infectious diseases in vertebrates while parvovirus refers to any of a class of very small viruses chiefly affecting animals, especially one (canine parvovirus) which causes contagious disease in dogs.

Size of the Virus

Usually, poxvirus is the largest form of DNA virus while parvovirus is the smallest type of virus.

Genome Size

The size of the genome of the poxvirus is 86 kb while the size of the genome of the parvovirus is 5.5 kb.

Genome

The poxviral genome contains double-stranded DNA while the parvoviral genome is single-stranded.

Structure

Poxvirus is a brick-shaped or oval-shaped virus, containing multiple membranes surrounding the core while parvovirus is a non-enveloped, icosahedral-shaped virus.

Examples

Monkeypox virus, orf virus, and molluscum contagiosum are examples of poxvirus while parvovirus B19 and canine parvovirus are examples of parvovirus.

Conclusion

In brief, poxvirus is the largest form of virus and parvovirus is the smallest form of a virus. The size of the genome of the poxvirus is 86 kb while the size of the genome of the parvovirus is 5.5 kb. Therefore, the main difference between poxvirus and parvovirus is their size. However, both poxvirus and parvovirus cause diseases in humans and other animals. Monkeypox virus and orf virus are examples of poxvirus while parvovirus B19 and canine parvovirus are examples of parvovirus. 

References:

1. “Poxvirus.” Centers for Disease Control and Prevention, Centers for Disease Control and Prevention, 24 Jan. 2020.
2. Pattison JR, Patou G. Parvoviruses. In: Baron S, editor. Medical Microbiology. 4th edition. Galveston (TX): University of Texas Medical Branch at Galveston; 1996. Chapter 64.

Image Courtesy:

1. “Double fertilization in arabidopsis 2” By Double_fertilization_in_arabidopsis.jpg: – Own work (CC BY-SA 4.0) via Commons Wikimedia
2. “Abb2.3 Pilze Fungi Basidiomycota Schnalle Hyphe Dikaryon 2021 (M. Piepenbring)” By Meike Piepenbring – Own Work (CC BY-SA 4.0) via Commons Wikimedia