Isolation of rotavirus from asymptomatic dogs in Brazil [Isolamento de rotavírus de cães assintomáticos no Brasil]

Rotaviruses (Reoviridae: Rotavirus), the causative agents of acute diarrhea in mammals, including man and birds, possess a nonenveloped triple-layered icosahedral capsid about 75nm diameter, with a characteristic 11segmented genome of double-stranded RNA (dsRNA) (Estes and Cohen, 1989). The genus Rotavirus is subdivided both serologically, based on the inner capsid VP6 protein, and electropherotypically, based on the arrangement of the 11 dsRNA segments, into seven groups (A to G). Groups A, B, and C are found in both humans and animals, whereas groups D, E, F, and G have been found only in animals to date. In most cases, the electrophoretic pattern of the genome of group A rotaviruses is composed of four high-molecular-weight dsRNA segments (numbered 1 to 4), two middle-sized segments (5 and 6), a distinctive triplet of segments (7 to 9), and two smaller segments (10 and 11) (Estes and Kapikian, 2007).