Identification of viruses with bi- and trisegmented double-stranded RNA genome in faeces of children with gastroenteritis.

Polyacrylamide gel electrophoresis of nucleic acid extracted from faecal samples of diarrhoeic children revealed the presence of group A rotavirus in 50 (23.4%) samples and group C rotavirus in 1 (0.5%) sample out of 214 tested. One other sample showed the presence of three bands (with apparent length of 2.92, 2.37 and 1.32 kbp) which by enzymatic digestion analysis, were shown to consist of double-stranded RNA (dsRNA). The sample was shown by electron microscopy to contain virus particles with a diameter of 32-34 nm. On the basis of morphology and genomic characteristics, this virus closely resembles a virus hitherto described only in chickens by Leite et al. in 1990 and tentatively named "picotrirnavirus". From the same group of 214, one sample containing a "picobirnavirus" was also identified. Thus, small icosahedral viruses with either a bior trisegmented dsRNA genome appear to infect humans. However, their pathogenic potential remains to be established.