Parvovirus

Parvovirus
Virus classification
Group:	Group II (ssDNA)
Family:	Parvoviridae

Parvovirus is the common name applied to all the viruses in the Parvoviridae taxonomic family. The Parvoviridae family has two subfamilies; the Parvovirinae (vertebrate viruses) and the Densovirinae (invertebrate viruses). Different examples can be given for the subfamily Parvovirinae but the most common is Dependovirus, which only work with a helper virus such as adenovirus. Other viruses that can infect without helper viruses are called as autonomous parvoviruses.

Parvoviruses are linear, non-segmented single-stranded DNA viruses, with an average genome size of 5000 nucleotides. They are classified as group II viruses in the Baltimore classification of viruses. Parvoviruses are among the smallest viruses (hence the name, from Latin parvus meaning small) and are 18–28 nm in diameter.

Parvoviruses can cause disease in some animals, including starfish and humans. Because the viruses require actively dividing cells to replicate, the type of tissue infected varies with the age of the animal. The gastrointestinal tract and lymphatic system can be affected at any age, leading to vomiting, diarrhea and immunosuppression but cerebellar hypoplasia is only seen in cats that were infected in the womb or at less than two weeks of age, and disease of the myocardium is seen in puppies infected between the ages of three and eight weeks.

Perhaps due to their extremely small size, parvoviruses were only recently discovered. Dependoviruses, the first parvoviruses to be discovered, were first isolated in the 1960s.Parvovirus B19, the first known parvovirus to infect humans, was discovered in London by Australian virologist Yvonne Cossart in 1974. Cossart and her group were focused on hepatitis B and were processing blood samples when they discovered a number of "false positives" later identified as parvovirus B19. The virus is named for the patient code of one of the blood bank samples involved in the discovery.

...
Wikipedia