The zoonotic potential of some human gastrointestinal viruses

Abstract

Viral gastroenteritis is a major cause of severe acute gastroenteritis among infants and young children throughout the world. The current study was conducted to investigate the possible role of animals in the epidemiology of human rotavirus strains and human astrovirus to give insights about the zooanthroponotic transmission cycle of such strains in rural settings. For this purpose, stool specimens were collected from 52 diarrheic children inhabiting rural settings as well as fecal samples from 38 diarrheic calves and 92 rats (88 Rattus rattus norvigecus and 4 Rattus rattus rattus). All human and animal samples were firstly screened for the presence of rotavirus using ELISA kit. Afterwards, all ELISA positive samples were then examined for the occurrence of human rotavirus using RT-PCR. Of 52 diarrheic children, 8 were positive for human rotavirus giving prevalence 15.4%, whereas the prevalence of human rotavirus among examined animals was 2.6% and 3.3% for calves and rats respectively. Seriously, the blasting and phylogenetic analysis of randomly selected one human and one rat sequences revealed 99% and 98% identity with human rotavirus genotype G3P[8] respectively. Furthermore, fecal samples from 44 diarrheic cattle (12 adult cattle and 32 calves) and 40 rats (36 (Rattus rattus norvigecus) and 4 (Rattus rattus rattus)) were examined for the detection of human astrovirus firstly by ELISA then RT-PCR confirmation. Of 44cattle, two were confirmed positive samples for human astroviruses, with prevalence 4.5%, whereas, among rat samples, two positive samples could be detected by ELISA however such samples were negative by RT-PCR. In conclusion, both human rotavirus and human astrovirus may circulate among cattle and rats and thus the reverse zoonotic transmission cycle cannot be ruled out in rural settings.