Gastroenteritis and the novel picornaviruses aichi virus, cosavirus, saffold virus, and salivirus in young children.

Background: During the last few years many new human picornaviruses have been discovered due to advances in metagenomics and other molecular biological approaches. The clinical significance and the occurrence are only sparsely described.

Objectives: To determine the epidemiology and clinical significance of infections with the novel human picornaviruses, aichi virus, cosavirus, salivirus, and saffold virus in infants in Denmark.

Study Design: We tested 1393 stool samples from a birth cohort of 454 children for these viruses. Samples were collected at ages 6, 10 and 15 months, and at episodes of gastroenteritis. Samples were tested by real-time reverse-transcriptase polymerase chain reaction assays. Each study participant had a diary, where the parents reported episodes of disease, including gastroenteritis.

Results: Aichi virus, salivirus and saffold virus were detected in 6, 9 and 38 of the children, respectively, but cosavirus was not detected in any of the children. There was a clear seasonal variation with most infections occurring in autumn and winter. A statistically significant association between the findings of salivirus and gastrointestinal disease was demonstrated. There was no association between gastrointestinal disease and the presence of aichi virus or saffold virus.

Conclusions: The newly discovered human picornaviruses aichi virus, saffold virus, and salivirus are circulating in Danish children, with the most common being saffold virus. Saffold virus was seen almost exclusively in the autumn and winter period. Salivirus was the only virus, which was significantly associated with gastroenteritis, although the number of positive samples was rather low.