Mammalian orthoreovirus infections
Don't need the entire report?
Generate a print friendly version containing only the sections you need.Generate report
IdentityTop of page
Preferred Scientific Name
- Mammalian orthoreovirus infections
OverviewTop of page
Mammalian orthoreoviruses (MRVs) have a wide geographic distribution and have been isolated from many mammals, including humans, rodents, horses, cattle, sheep, pigs, cats and dogs (McVey et al., 2013). The name “reovirus” was derived from “respiratory-enteric orphan virus” as the viruses are associated with the respiratory and alimentary tracts, usually without clinical manifestations (Sabin, 1959). However, MRVs are sometimes isolated from animals and humans with (generally mild) respiratory and/or enteric disease (McVey et al., 2013).
Since 2004, there have been reports of MRVs as the sole pathogen in humans presenting severe clinical manifestations and there is increasing concern about the widespread nature and pathogenesis of these viruses and their potential for evolution into a more virulent form (Ouattara et al., 2011; Steyer et al., 2013). Similar viruses have been found in humans and bats, and it has been speculated that these viruses might be zoonotic pathogens (Lelli et al., 2013; Steyer et al., 2013).
Although not a significant veterinary pathogen, cases or outbreaks of disease associated with MRVs have occasionally been reported, including diarrhoea in calves (Goto et al., 1981; Chang et al., 2008; Anbalagan et al., 2014), respiratory disease in calves (Flammini et al., 1980), respiratory and intestinal disease in lambs (Belak and Palfi, 1974; Belak et al., 1974), diarrhoea in cats (Muir et al., 1992; Mochizuki and Uchizono, 1993), respiratory disease in horses (Thein and Mayr, 1974; Thein and Hartl, 1976) and diarrhoea in dogs (Decaro et al., 2005).
Several strains of porcine orthoreoviruses have been isolated from diarrhoeic pigs in China (Zeng et al., 2008; He et al., 2013), South Korea (Kwon et al., 2012) and Japan (Fukutomi et al., 1996). As part of an investigation into devastating outbreaks of porcine epidemic diarrhoea in the United States since May 2013, Narayanappa et al. (2015) discovered a novel mammalian orthoreovirus type 3 (MRV3) in faeces of pigs from these outbreaks and in ring-dried swine blood meal. Neonatal piglets experimentally infected with MRV3 or a chloroform extract of swine blood meal developed severe diarrhoea and acute gastroenteritis with 100% mortality within 3 days post-infection. Genetic and phylogenetic analyses of two MRV3 isolates revealed that they differed significantly from non-pathogenic mammalian orthoreoviruses circulating in the USA. The authors concluded that the novel porcine MRV3 may contribute to enteric disease along with other swine enteric viruses (swine enteric coronaviruses, porcine epidemic diarrhea virus and porcine deltacoronavirus).
Hosts/Species AffectedTop of page
MRVs infect a wide range of mammals, including humans, rodents, horses, cattle, sheep, pigs, cats and dogs, usually without clinical manifestations (McVey et al., 2013).
DistributionTop of page
MRVs are distributed worldwide, but are rarely associated with disease (Attoui et al., 2011). The distribution table lists reports of MRVs associated with enteric or respiratory diseases in livestock.
Distribution TableTop of page
The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.
|Continent/Country/Region||Distribution||Last Reported||Origin||First Reported||Invasive||Reference||Notes|
|China||Present||Chang et al., 2008; Zeng et al., 2008|
|Japan||Present||Goto et al., 1981; Fukutomi et al., 1996|
|Korea, Republic of||Present||Kwon et al., 2012|
|USA||Present||Present based on regional distribution.|
|-Indiana||Present||Anbalagan et al., 2014|
|-Iowa||Present||Narayanappa et al., 2015|
|-Minnesota||Present||Narayanappa et al., 2015|
|-North Carolina||Present||Narayanappa et al., 2015|
|Germany||Present||Thein and Hartl, 1976|
|Hungary||Present||Belak and Palfi, 1974; Belak et al., 1974|
|Italy||Present||Flammini et al., 1980|
PathologyTop of page
Human orthoreoviruses generally do not produce symptoms, but occasionally may cause respiratory disease and enteritis, particularly in infants and children (Attoui et al., 2011). However, since 2004, there have been reports of MRVs as the sole pathogen in humans presenting severe clinical manifestations, including acute necrotizing encephalopathy (Ouattara et al., 2011) and acute gastroenteritis (Steyer et al., 2013). There is concern about the emergence of more virulent MRV strains in both humans and other mammals (Decaro et al., 2005; Lian et al., 2013; Steyer et al. 2013).
Although reovirus infection of humans usually induces mild symptoms, infection of newborn mice leads to severe pathologic conditions, depending on the inoculation route and strain (Tyler et al., 1986). Orthoreovirus infection can cause diarrhoea, runting, oily hair syndrome, hepatitis, jaundice, myocarditis, myositis, pneumonitis, encephalitis and hydrocephalus (Attoui et al., 2011).
In domestic animals, respiratory disease and/or enteritis have occasionally been reported, mostly in neonatal/young animals.
A reovirus was isolated from nasal and rectal swabs of lambs during an outbreak of respiratory and intestinal disease in Hungary (Belak et al., 1974). Experimental infection (intratracheal and intranasal) of 2- to 4-week-old lambs with reovirus strain type 1 (H/11) caused a rise in temperature, ocular and nasal discharge, sneezing, dyspnoea and diarrhoea after 4-6 days. Enteritis, catarrh in the upper airways, and diffuse interstitial pneumonia were observed in lambs killed 8 days after infection (Belak and Palfi, 1974).
Reoviruses have been isolated from diarrhoeic calves in China (Chang et al., 2008) and the USA (Anbalagan et al., 2014). Genome sequencing suggested that the U.S. strain is a novel reassortant MRV1 (Anbalagan et al., 2014). Goto et al. (1981) reported that a reovirus was isolated from calves with both respiratory and intestinal symptoms in Japan.
Porcine orthoreoviruses causing diarrhoea have been reported in China (Zeng et al., 2008; He et al., 2013), South Korea (Kwon et al., 2012) and Japan (Fukutomi et al., 1996). As part of an investigation into devastating outbreaks of porcine epidemic diarrhoea in the United States, Narayanappa et al. (2015) discovered a novel mammalian orthoreovirus type 3 (MRV3) in faeces of pigs from these outbreaks and in ring-dried swine blood meal. Neonatal piglets experimentally infected with MRV3 developed severe diarrhoea and acute gastroenteritis with 100% mortality within 3 days post-infection. Gross lesions, such as catarrhal enteritis and intussusception were observed. Small intestines showed mild to severe villous blunting and fusion, occasional villous epithelial syncytial cells, swollen epithelial cells with granular cytoplasm and multifocal necrosis of mucosal epithelium, and round to oval vacuoles in the intestinal epithelial cells. In a few pigs, protein casts in renal tubules, minimal to mild hepatic lipidosis and hepatocellular vacuolar changes, and mild to moderate suppurative bronchopneumonia were also seen.
MRVs have been isolated from a dog with respiratory disease in China (Shen et al., 1999) and from a dog with fatal diarrhoea (concurrently infected with canine parvovirus type 2) in Italy (Decaro et al., 2005).
A novel MRV strain was isolated from farmed mink (Mustela vison) with diarrhoea in Hebei Province in northern China (Lian et al., 2013). The morbidity rate was almost 100%, with a mortality rate <5%, mainly in mink <3 months of age. Clinical signs included anorexia, emaciation, unkempt fur, and diarrhoea. There was a close genetic relationship between the novel mink reovirus and strains from humans and pigs. It is suggested that the novel mink reovirus resulted from reassortment of human and swine strains.
DiagnosisTop of page
Reovirus infections can be diagnosed by virus isolation or detection, and by serology. Virus can be isolated from tissues and from rectal, nasal, and throat swabs by cell culture techniques. Virus isolates can be serotyped by either haemagglutination inhibition or virus neutralization (VN) testing with serotype-specific antisera. Reoviruses can be identified in tissues or cell culture by immunofluorescent antibody staining or immunohistochemistry. Serologic testing is done using paired sera and VN or enzyme-linked immunosorbent assay (ELISA) (McVey et al., 2013).
EpidemiologyTop of page
MRVs have a wide distribution and are commonly present in river water, untreated sewage and stagnant water, likely reflecting faecal contamination by infected animals and/or humans (McVey et al., 2013).
Transmission is by an enteric or respiratory route, no arthropod vectors are involved (Attoui et al., 2011).
MRVs are fairly common, but the infection produced is usually asymptomatic or causes a mild disease, generally only in the very young (Sabin, 1959).
Zoonoses and Food SafetyTop of page
The discovery of similar MRVs in bats and humans has led to speculation of possible bat-to-human interspecies transmission (Lelli et al., 2013; Steyer et al., 2013). A closely related MRV was also identified in a dog with haemorrhagic enteritis and it has been suggested that these viruses might be important zoonotic pathogens (Decaro et al., 2005; Steyer et al., 2013).
Disease TreatmentTop of page
Since reovirus infection in mammals is usually mild, treatment is not required; no vaccines or control measures have been described and are unlikely to be developed unless reoviruses become of greater veterinary significance (McVey et al., 2013).
ReferencesTop of page
Anbalagan S; Spaans T; Hause BM, 2014. Genome sequence of the novel reassortant mammalian orthoreovirus strain MRV00304/13, isolated from a calf with diarrhea from the United States. Genome Announcements, 2(3):e00451-14. http://genomea.asm.org/content/2/3/e00451-14.full
Attoui H; Mertens PPC; Becnel J; Belaganahalli S; Bergoin M; Brussaard CP, 2011. Family: Reoviridae. In: Virus Taxonomy: Ninth Report of the International Committee on Taxonomy of Viruses [ed. by King, A. M. Q. \Adams, M. J. \Carstens, E. B. \Lefkowitz, E. J.]. London, UK: Elsevier Inc, 541-637.
Belak S; Palfi V; Huszar E, 1974. [Mass respiratory and intestinal disease of lambs caused by a reovirus]. (Baranyok reovirus okozta tomeges legzo- es emesztoszervi megbetegedese.) Magyar Allatorvosok Lapja, 29(No.1):14-16.
Chang JiTao; Li Xin; Zhang YaKe; Yu Li, 2008. Isolation and identification of bovine reovirus from feces of the calves suffered from diarrhea. Zhongguo Yufang Shouyi Xuebao / Chinese Journal of Preventive Veterinary Medicine, 30(9):711-715. http://zgxq.chinajournal.net.cn
Decaro N; Campolo M; Desario C; Ricci D; Camero M; Lorusso E; Elia G; Lavazza A; Martella V; Buonavoglia C, 2005. Virological and molecular characterization of a mammalian orthoreovirus type 3 strain isolated from a dog in Italy. Veterinary Microbiology, 109(1/2):19-27.
He XiaoMing; Yao HuoChun; Zhang HongBiao; Lin Tao; Yuan ShiShan; Long JinXue; Ding Chan, 2013. Isolation and identification of a strain of porcine reovirus serotype 1 in China. Chinese Veterinary Science / Zhongguo Shouyi Kexue, 43(1):22-29. http://www.zgsykx.com/
Kwon HyungJun; Kim HaHyun; Kim HyunJeong; Park JunGyu; Son KyuYeol; Jung Juyeon; Lee WooSong; Cho KyoungOh; Park SuJin; Kang MunIl, 2012. Detection and molecular chracterization of porcine type 3 orthoreoviruses circulating in South Korea. Veterinary Microbiology, 157(3/4):456-463. http://www.sciencedirect.com/science/journal/03781135
Lelli D; Moreno A; Lavazza A; Bresaola M; Canelli E; Boniotti MB; Cordioli P, 2013. Identification of mammalian orthoreovirus type 3 in Italian bats. Zoonoses and Public Health, 60(1):84-92. http://onlinelibrary.wiley.com/doi/10.1111/zph.12001/abstract
Lian Hai; Liu Ye; Zhang ShouFeng; Zhang Fei; Hu RongLiang, 2013. Novel orthoreovirus from mink, China, 2011. Emerging Infectious Diseases, 19(12):1985-1988. http://wwwnc.cdc.gov/eid/article/19/12/pdfs/13-0043.pdf
McVey DS; Wilson W; Drolet B, 2013. Reoviridae. In: Veterinary Microbiology [ed. by McVey, D. S. \Kennedy, M. \Chengappa, M. M.]. Ames, Iowa, USA: Wiley-Blackwell, 491-500.
Narayanappa AT; Sooryanarain H; Deventhiran J; Cao DJ; Venkatachalam BA; Kambiranda D; LeRoith T; Heffron CL; Lindstrom N; Hall K; Jobst P; Sexton C; Meng XJ; Elankumaran S, 2015. A novel pathogenic mammalian orthoreovirus from diarrheic pigs and swine blood meal in the United States. mBio, 6(3):e00593-15. http://mbio.asm.org/content/6/3/e00593-15.full
Ouattara LA; Barin F; Barthez MA; Bonnaud B; Roingeard P; Goudeau A; Castelnau P; Vernet G; Paranhos-Baccalà G; Komurian-Pradel F, 2011. Novel human reovirus isolated from children with acute necrotizing encephalopathy. Emerging Infectious Diseases, 17(8):1436-1444. http://www.cdc.gov/eid/content/17/8/101528.htm
Steyer A; Gutiérrez-Aguire I; Kolenc M; Koren S; Kutnjak D; Pokorn M; Poljsak-Prijatelj M; Racki N; Ravnikar M; Sagadin M; Steyer AF; Toplak N, 2013. High similarity of novel orthoreovirus detected in a child hospitalized with acute gastroenteritis to mammalian orthoreoviruses found in bats in Europe. Journal of Clinical Microbiology, 51(11):3818-3825. http://jcm.asm.org/content/51/11/3818.abstract
Thein P; Hartl G, 1976. Isolation of a reovirus from a horse with respiratory disease. (Isolierung eines Reovirus aus einem respiratorisch erkrankten Pferd.) Zentralblatt fur Veterinarmedizin, 23B(8):698-701.
Thein P; Mayr A, 1974. [Studies on the significance of reovirus infections in respiratory diseases of horses]. (Untersuchungen uber die Bedeutung von Reovirus-Infektionen fur respiratorische Erkrankungen beim Pferd.) Zentralblatt fur Veterinarmedizin, 21B(Heft 4):219-233.
Tyler KL; McPhee DA; Fields BN, 1986. Distinct pathways of viral spread in the host determined by reovirus S1 gene segment. Science, 233(4765):770-774.
Wenske EA; Chanock SJ; Krata L; Fields BN, 1985. Genetic reassortment of mammalian reoviruses in mice. Journal of Virology, 56:613-616.
Zeng ZhiYong; Guo WanZhu; Xu ZhiWen; Liang HaiYing; Song ZhenHui; Yin HuaPing; Wang Xin; Wang XiaoYu, 2008. Isolation of reovirus SC-A strain from fecal of diarrhea pigs and sequence analysis of sigma2 gene. Chinese Journal of Veterinary Science, 28(7):799-803, 808. http://zgsyxb.periodicals.net.cn/default.html
Distribution MapsTop of page
Unsupported Web Browser:
One or more of the features that are needed to show you the maps functionality are not available in the web browser that you are using.
Please consider upgrading your browser to the latest version or installing a new browser.
More information about modern web browsers can be found at http://browsehappy.com/