Ross goose hepatitis B virus Rghbv An

unassigned virus in the family Hepadnaviridae.

Ross River virus (RRV) A species in the genus Alphavirus. Isolated from birds and mosquitoes in Fiji, and Queensland and New South Wales, Australia. Causes a febrile illness and rash with arthralgia in humans. The vectors are the mosquitoes, Aedes vigilax and Culex annulirostris. Antibodies are present in horses, cattle, sheep, dogs, rats, bats and kangaroos in northern and eastern Australia, New Guinea and northern Solomon Islands.

Aaskov JG and Davies CEA (1979) J Immun Meth 25, 37

Mackenzie JS et al (1994) Arch Virol 136, 447

Rost Island virus (RSTV) A serotype of Great Island virus in the genus Orbivirus, belonging to the Great Island complex.

Rotavirus A genus of the family Reoviridae. Virion diameter 100 nm. The icosahedral capsid is triple-layered with a clearly defined outer layer, appearing like the rim of a wheel, while the inner layers gives the appearance of spokes, hence the name. 132 channels extend inward from the surface to the core, and 60 short spikes extend outward from the surface. The outer layer is often removed spontaneously so that both triple-layered smooth and double-layered rough virions are found in the gut contents. Virus replicates in intestinal epithelial cells. Genome RNA is double-stranded with 11

Rotavirus

segments from 667 bp to 3.3kb long. Buoyant density of 1.36g/ml in CsCl. On polyacrylamide gel fractionation, eight structural polypeptides and six non-structural polypeptides can be identified. There are strains causing acute gastroenteritis in humans, especially infants, and in numerous other hosts such as calves, mice, piglets, lambs, foals, rabbits, antelope, hares, chickens, turkeys and chimpanzees. Very large numbers of particles are present in the feces and are detected by electron microscopy. Many species are difficult to replicate in cell cultures, but most strains can be grown in simian kidney cell lines if trypsin is added to the culture medium. Rotaviruses can be divided into seven groups (A to G) on the basis of the VP6 inner capsid protein, the group-specific antigen. Within group A, a subdivision into subgroups I and II is possible using anti-VP6 monoclonal antibodies. There are two type-specific antigens: VP4 (HA) and VP7. At least 14 serotypes of group A (G1-G14) based on VP7, and 11 serotypes of group A (P1-P11) based on VP4 are recognized. These can be discriminated either by reactions with monoclonal antibodies or polyclonal antibodies to baculovirus expressed proteins or to rotavirus reassortants, or using sequence-specific nucleic acid probes or genotype-specific reverse transcription-polymerase chain reaction primers. Rotaviruses cause diarrhea in the species that they infect which may be due in part to lysis of intestinal enterocytes. Virus particles are found in the columnar epithelial cells, goblet cells, phagocytic cells and M cells in the small intestine. In children, rotavirus gastroenteritis commonly occurs between the ages of 3 months and 2 years, and in other age groups infections may be asymptomatic. In developing countries, it is estimated that rotavirus infections cause about 870000 deaths annually, especially in malnourished children. Oral rehydration therapy is very effective where it has been used, but the development of an attenuated rotavirus vaccine is probably the best long-term strategy for controlling rotavirus disease. One vaccine, known as Rotashield™, was licensed for a short period in the USA but withdrawn in 2000 because of a higher than normal incidence of intussusception in recipients. Vaccine development efforts are continuing because of the high burden of rotavirus disease, especially in developing countries.

Synonyms: duovirus; reovirus-like agent; stellavirus.

Desselberger U (1996) Adv Virus Res 46, 69 Ramig RF (1994) Curr Top Microbiol Immun 185, 380 pp

Shaw RD and Greenberg HB (1999) In Encyclopedia of Virology, Second edition, edited by A Granoff and RG Webster. London: Academic Press, p. 1576

Rotavirus A (ROTAV A) A species in the genus Rotavirus. The most common cause of diarrheal disease in infants and young children, constituting more than 95% of currently identified strains in humans worldwide. All group A rotaviruses share a common antigen, VP6, the major inner capsid protein. There are two subgroups, I and II, comprising a number of serotypes. In addition, the viruses are classified as G types (G from glycoprotein) based on VP7, and P types (P from protease-sensitive protein) based on VP4. At least 15 different G types and more than 20 different P types have so far been described. These designations are partly based on sequence analysis (genotypes) where complete serology is missing, so the G or P types may fall into different subgroups. For example, the G (VP7) serotypes 1, 3 or 4 are in subgroup II, whilst subgroup I rotaviruses belong to G serotype 2. Group A rotaviruses are ubiquitous worldwide, and include the prototype rotavirus, simian rotavirus SA11.

Bellamy AR and Both GW (1990) Adv Virus Res 38, 1

Burke B and Desselberger U (1996) Virology 218, 299

Ramig RF (editor) (1994) Curr Top Microbiol Immun 185, 380 pp

Rotavirus B (ROTAV B) A species in the genus Rotavirus. A major cause of severe adult diarrheal disease in China, where it was identified in 1983. In the USA, only 5% of the population is seropositive for group B rotaviruses. Causes infectious diarrhea of infant rats, and has also been found in pigs, calves and sheep. Synonym: adult diarrheal rotavirus (ADRV).

Rowson-Parr virus

Rotavirus C (ROTAV C) A species in the genus Rotavirus. Originally termed 'pararotaviruses' when found in 1982-83 in infants in Australia, Brazil and France. Other than humans, pigs and cattle have been found to be infected. The prototype is the porcine Cowden strain. Epidemic outbreaks have occurred in England and Japan. Agglutinate human and sheep ery-throcytes. Closely related to group A rotaviruses

Rotavirus D (ROTAV D) A species in the genus Rotavirus, only identified so far in birds. The prototype is the chicken 132 strain. Most natural infections involve young birds, less than 6 weeks of age. Turkeys, chickens, pheasants and ducks are all susceptible.

Rotavirus E (ROTAV E) A species in the genus Rotavirus, found in pigs. Unrelated antigenically to groups A, B, C, D and F. The prototype is the porcine DC-9 strain.

rotavirus F (ROTAV F) A tentative species in the genus Rotavirus, only so far identified in birds. The prototype is the chicken A4 strain.

rotavirus G (ROTAV G) A tentative species in the genus Rotavirus, only so far identified in birds. The prototype is the chicken 555 strain.

rougeole virus Synonym for Measles virus.

rough membrane Endoplasmic reticulum encrusted with ribosomes. See also smooth membrane.

Rous-associated virus (RAV) An avian leukemia virus which acts as a helper for defective Rous sarcoma virus, providing information for the coat and thus controlling surface antigens and host range. See Avian leukosis virus, genus Alphavirus.

Rous sarcoma virus (RSV) A species in the genus Alpharetrovirus. The first virus demonstrated, in 1911, to cause a solid malignant tumor; Peyton Rous waited 56 years before receiving the Nobel Prize for his work in 1966, shortly before his death at the age of 91 in 1970, the year that reverse transcriptase was discovered. There are a number of strains of RSV

varying in their oncogenicity and host range. Some will produce tumors in mammals such as rats, cotton rats, guinea pigs, mice, hamsters and monkeys. Some are replication-competent, but most are defective and require a leukemia virus to code for the viral envelope which determines host range. Transforms cells in culture which do not produce infective virus unless also infected with a leukemia virus. Transformed cells cannot be maintained indefinitely in culture. The genome of the virus contains the v-src oncogene sequence which is not present in leukemia viruses and is responsible for cell transformation leading to solid tumor formation.

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