Rotaviiruse

Rotaviruses are a genus of non-enveloped, double-stranded RNA viruses in the family Reoviridae. They have a triple-layered icosahedral capsid and a segmented genome consisting of 11 dsRNA segments. The outer capsid proteins VP7 and VP4 define the G and P serotypes, respectively, which drive much of the genetic and antigenic diversity seen in circulating strains.

Rotaviruses primarily infect the mature enterocytes lining the small intestine, causing cell loss and disruption of absorptive function. The resulting gastroenteritis is typically characterized by sudden onset of watery diarrhea, vomiting, fever, and abdominal cramps. Infants and young children are most at risk for severe dehydration, especially in settings with limited access to fluids.

Transmission is mainly fecal-oral and can occur via person-to-person contact, contaminated surfaces, or water. Rotavirus shares environmental stability and high contagiousness, contributing to frequent outbreaks in childcare centers and hospitals. Immunity develops with exposure but protection wanes, so repeated infections occur, usually becoming milder with age.

Diagnosis is usually based on clinical presentation and laboratory testing of stool samples using antigen detection or molecular methods such as RT-PCR.

Treatment is supportive care, with emphasis on oral or intravenous rehydration and zinc supplementation. There are no routinely used antiviral drugs for routine treatment.

Prevention relies on vaccination and hygiene measures. Two widely used vaccines for infants, Rotarix and RotaTeq, are administered in early infancy in many countries and have substantially reduced the incidence of severe rotavirus gastroenteritis. Good hand hygiene and clean water help reduce transmission, but vaccination remains the most effective public health tool against severe disease.