The Parvoviridae is a family of small, non-enveloped viruses that contain a single-stranded DNA genome of approximately 5,000 bases. Positive and negative DNA strands are packaged into separate virions in an equal proportion and can be classified by size, morphology, and genomic organization.
Members of the family Parvoviridae infect a wide variety of hosts, ranging from insects to primates, with replication taking place in the nucleus of dividing cells. Generally, parvoviruses cause a wide range of acute or chronic diseases; however, many of them are not known to be associated with any disease.
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Parvoviruses in humans
Parvovirus B19, which is a widespread virus that is pathogenic for humans, is a member of the Erythroparvovirus genus in the Parvoviridae family. This parvovirus was discovered serendipitously in 1975 when blood donors were screened for hepatitis B. The virus is widespread, with a myriad of various manifestations that depend on the immunologic and hematologic status of the host.
Characteristics of such an ample range of pathologies and outcomes depend on the interplay between the pathogenetic potential of the virus, its adaptation to diverse cellular environments, and the physiological and immune status of the infected individuals. Moreover, parvovirus B19 can cause aplastic anemia in patients with sickle cell disease, a fifth disease with erythema infectiosum in children, arthropathy in adults, and rare fetal infections.
Parvovirus | Dr. Scott Zashin | Top10MD
The virus has a marked tropism for erythroid progenitor cells in the bone marrow, exerting a cytotoxic effect and causing a block in erythropoiesis that can be manifested as erythroid aplasia. Wide circulation of the virus, combined with a prevalent benign and self-limiting clinical course, generally leads to a diminished appreciation of its pathogenetic potential.
Adenoassociated viruses (AAV) are also members of the Parvoviridae family that appear to infect humans without causing clinical manifestations. Moreover, AAV has been used as vectors for gene transduction and gene therapy. The first human AAV was discovered in 1965 as a contaminant of adenovirus preparations.
Parvoviruses in animals
Parvoviruses in dogs are potentially fatal infections that can damage the intestines and cause severe diarrhea and dehydration. Canine parvovirus type 2 (CPV-2) emerged in late 1970s, during which it caused severe epizootics in kennels and dog shelters worldwide and soon became endemic in the global dog population.
Parvovirus in Dogs: Causes, Symptoms, and Treatment Options
Feline panleukopenia virus has an almost identical DNA sequence as canine parvovirus; however, this virus does not harm dogs. Instead, feline panleukopenia causes disease in all felids, as well as in some members of related families, such as raccoons or minks. This virus is commonly referred to as feline distemper and causes fever, low white blood cell count, diarrhea, and sometimes even death.
Porcine parvovirus is the major causative virus in a reproductive failure syndrome in swine. The characteristic symptoms of porcine parvovirus are grouped under the acronym SMEDI. To this end, SMEDI stands for stillbirths, mummified fetuses, early embryonic death, and infertility. This infection has been reported to occur worldwide with variable prevalence rates.
Two specific parvoviruses of rats known as Kilham rat virus (RV) and H-1 virus are highly pathogenic for fetal and infant rats. Although the infections are usually subclinical, they can also seriously damage the central nervous system, liver, lymphoid system, and other tissues. In colonies where the infection is endemic, a majority of rats develop antibodies and become immune by the time they are seven months old.
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