Rotavirus Infections is a non-enveloped, double-stranded RNA virus; rota (Latin; “wheel”) for shape of the capsid; genus within the family Reoviridae; relatively resistant to environmental destruction (acid and lipid solvents); unique double capsid protects virus from inactivation in the upper gastrointestinal tract.
Wide host range, identified in almost every species investigated.
Most significant cause of severe gastroenteritis in young children (< 2 years) and animals throughout the world.
Transmission—fecal-oral contamination.
Infection—affects mature epithelial cells on luminal tips of the intestinal villi; causes swelling, degeneration, and desquamation; denuded villi contract; results in villous atrophy with loss of absorptive capability and loss of brush border enzymes (e.g., disaccharidases); leads to osmotic diarrhea.
SIGNALMENT
Dogs and cats.
Pups < 12 weeks old and more often < 2 weeks old—diarrhea.
Kittens and young cats (< 6 months of age)—more susceptible to infection.
SIGNS
Dogs—most infections subclinical or limited to relatively mild, nonspecific, watery to mucoid diarrhea, anorexia, and lethargy; rare fatalities reported.
Cats—primarily subclinical or mild diarrhea; more severe clinical disease may occur with co-infections or in stressed conditions.
CAUSES & RISK FACTORS
Rotavirus.
Young animals with immature immune systems at increased risk.
Presence of other enteric pathogens.
Overcrowding (virus stable in environment).
DIAGNOSIS
DIFFERENTIAL DIAGNOSIS
Canine viral enteritis—canine parvovirus; canine coronavirus; canine astrovirus; canine calicivirus; canine herpesvirus; canine distemper virus; canine reovirus.
Feline viral enteritis—feline parvovirus (feline panleukopenia virus); FeLV; feline coronavirus; feline astrovirus; feline calicivirus.
Other causes of enteritis—bacteria (e.g., Salmonella, Campylobacter, Clostridium); fungi; protozoa; parasites; foreign bodies; intussusception; allergies; toxicants.
CBC/BIOCHEMISTRY/URINALYSIS
Non-contributory
OTHER LABORATORY TESTS
Serology—not recommended; most animals (e.g., 85% of dogs) carry antibodies owing to previous exposure or from passive antibody immunization transfer from the bitch or queen; must demonstrate four-fold difference in acute and convalescent serum samples.
Direct electron microscopy—detects virus in feces; rapid; lack of sensitivity.
Immunoelectron microscopy—more sensitive and specific than direct electron microscopy; not commonly available.
ELISA—detect common group rotavirus antigen in feces
Latex agglutination; Virogen Rotatest (
Immunochromatographic
Immunofluorescence.
Virus isolation.
PCR.
DIAGNOSTIC PROCEDURES
Histology—swollen small intestinal villi; mild infiltration by macrophages and neutrophils; virus detected by fluorescent antibody test.
TREATMENT
Symptomatic for diarrhea—fluids, electrolytes, and dietary restriction.
Antibiotic therapy not indicated.
Principal protection—probably antibodies in milk of immune bitch or queen.
MISCELLANEOUS
ZOONOTIC POTENTIAL
Rotaviruses are not host-specific; thus, affected puppy or kitten may pose a potential human health hazard, particularly for infants.
Exercise care when handling fecal material from pets with diarrhea.
Humans—diarrhea; infants in developed countries: high morbidity and low mortality (attributed to fluid therapy); infants and young children in developing countries: leading cause of life-threatening diarrhea (more than 600,000 deaths per year in children < 5 years old); in United States, prior to routine vaccination of infants which began in 2006, more than 3 million episodes of diarrhea, ∼500,000 clinic visits, ∼60,000 hospitalizations but only 20–40 deaths per year. In US, pentavalent rotavirus oral vaccine has reduced hospitalizations by 60–75%.
ABBREVIATIONS
ELISA = enzyme-linked immunosorbent assay
FeLV = feline leukemia virus
PCR = polymerase chain reaction
Visit your veterinarian as early recognition, diagnosis, and treatment are essential.