ROTAVIRUSES

Structure & Property	Transmission	Pathogenesis	Clinical findings	Laboratory diagnosis	Treatment	
Family: reovirus

Genome: double-stranded RNA, 11 segments.

Size:  70-90nm

Double-layered icosahedral capsid without an envelope. 

Not sensitive to lipid detergents.

Contain RNA-dependent RNA polymerase.

Viral haemagglutinin is type-specific antigen.

5 groups (A-E)

At least 6 serotypes	Fecal-oral route from case to case

Possible spread via respiratory secretions.

Infection is mainly endemic though outbreaks in adults have been reported.

Most often among the elderly in hospitals or residential homes.	Attach to cell surface at site of beta-adrenergic receptor.

Replicates in mucosal cells of small intestine.

Infect columnar epithelium, leading to loss of salt, glucose and water.

Intestinal IgA protects against reinfection.	Most common cause of gastroenteritis and diarrhea in young children worldwide.

Diarrhea (watery & non-bloody)

Nausea

Vomiting

Fever of > 38.5 degrees.

Dehydration

Severe disease in malnourished.

Incubation: 48 hrs

Diarrhea is self-lmiting.

	Diagnosis:
- detection of virus in stool by using radioimmunoassay or ELISA.
-detection of 4-fold or greater rise in antibody titer.

EM can be used to demonstrate virus in stool; not feasible for routine clinical use.

Virus cannot be cultured.	No antiviral therapy or vaccine available.

Prevention rests on sanitation.