Gastrointestinal Viruses: Picornaviridae Family

Study Notes

Noroviruses are easily transmitted through water, person-to-person, or in airborne droplets of vomitus.
The virus persists in water despite treatment processes.
The incubation period is 24 to 48 hours, followed by an abrupt onset of severe nausea, vomiting, diarrhea, and low-grade fever.

Reoviruses are non-enveloped, double-stranded RNA viruses composed of three concentric protein shells: outer shell, inner shell, and core.
Rotavirus is the major causative agent of infantile severe gastroenteritis worldwide.
Gastroenteritis caused by rotavirus can occur in children of all ages, but is most common in infants from 6 months to 3 years old.
Rotavirus occurs more frequently in the winter months in temperate climates.
Enzyme-linked immunosorbent assay (ELISA) and latex agglutination tests detect the viral antigens in fecal material.

Orbiviruses are a genus within the reovirus family and commonly infect insects, transmitting to vertebrates.
Many orbiviruses are transmitted by insects to vertebrates.

The Picornaviridae family consists of Enterovirus, Rhinovirus, Hepatovirus, Parechovirus, Aphthovirus, and Cardiovirus.
The first four groups contain important human pathogens.
Poliovirus, Coxsackie, Echovirus, and Enterovirus are transmitted through the fecal-oral route.

Adenovirus infection is associated with respiratory and gastrointestinal diseases.
Adenovirus serotypes 40 and 41 cause gastroenteritis in infants and young children, while other serotypes are associated with conjunctivitis and keratitis.
Adenoviruses can cause severe, acute respiratory disease epidemics in military recruits, resulting in considerable morbidity and mortality.
Adenovirus produces a characteristic grapelike cluster cytopathic effect (CPE).
Adenoviruses are stable and can be isolated in human embryonic kidney and many continuous epithelial cell lines.
Serotyping is accomplished by serum neutralization or hemagglutination inhibition.