Reovirus Infections

Phylogenetic analysis, genomic diversity and classification of M class gene segments of turkey reoviruses

“…The ARVs are ubiquitous in domestic poultry with 80% of them being non-pathogenic and are frequently found in clinically healthy birds (Jones, 2008). However, ARVs have also been known to cause different disease conditions in poultry including enteritis, hepatitis, neurological disorder, myocarditis, respiratory distress and viral arthritis/tenosynovitis (Jones, 2008).…”

Postvaccinal Reovirus Infection with High Mortality in Breeder Chicks

“…The ubiquity of this virus in the chicken normal intestinal flora and in the commercial avian housing makes a solid causal relationship difficult to establish between the presence of this virus and a disease as malabsorption syndrome. This is however not the case in VAT, in which many reovirus serotypes were identified as causal agents, such as the S1133 strain which is commonly included in modified-live and inactivated vaccines used to protect against this disease (5). Chickens are most susceptible to reovirus infection at one day of age.…”

“…Further investigation revealed that a S1133 reovirus vaccine labelled for drinking water administration in 10 to 17 week-old chickens was inadvertently subcutaneously administered to the day-old chicks. Since chickens are most sensitive to the pathogenic action of the ARV at a day of age, we postulate that a live vaccinal strain, even attenuated, could have the potential to induce such dramatic lesions in susceptible birds (5). It is interesting to note that, in one study, chicken orally inoculated with a reovirus strain rarely died (3% mortality) compared to those who were inoculated intramuscularly (54% mortality) (13).…”

“…This explains why vaccination is performed in breeders to protect newborns from this infection, which can be transmitted vertically (5). Experimental infection of one day-old chicks with a reovirus VAT strain has been demonstrated to cause liver necrosis in these birds as soon as 24 hours post-infection (9).…”

“…They are commonly found in healthy chickens but some serotypes are known to cause serious diseases such as viral arthritis/tenosynovitis (VAT) and malabsorption syndrome (5). The age of the bird at the time of infection, its immune status, the virus pathotype and the route of exposure are all important to determine the course of the disease and severity of clinical signs, ranging from asymptomatic to severe lack of performance or even mortality (5). The ubiquity of this virus in the chicken normal intestinal flora and in the commercial avian housing makes a solid causal relationship difficult to establish between the presence of this virus and a disease as malabsorption syndrome.…”