Intra- and Cross-Species Transmission of Astroviruses

Abstract

Astroviruses are non-enveloped, single-stranded RNA viruses that infect mammalian and avian species. In humans, astrovirus infections are one of the most common causes of gastroenteritis in children. Infection has also been linked to serious neurological complications, especially in immunocompromised individuals. More extensive disease has also been characterized in non-human mammalian and avian species. To date, astroviruses have been detected in over 80 different avian and mammalian hosts. As the number of hosts continues to rise, the need to understand how astroviruses transmit within a given species as well as to new host species becomes increasingly important. Here, we review the current understanding of astrovirus transmission, the factors that influence viral spread, and the potential for cross-species transmission. Additionally, we highlight the current gaps in knowledge and areas of future research that will be key to understanding astrovirus transmission and zoonotic potential.

Keywords: astrovirus; cross-species transmission; recombination; virus transmission; zoonotic potential.

Figure 1

Schematic representation of astrovirus genomic and subgenomic RNA organization. Genomic RNA is connected to the viral genome-linked protein (VpG) at the 5′ end (grey); subgenomic RNA may have a VpG but this has yet to be confirmed [13,14,15]. Three reading frames encode the viral proteins: proteases and VpG in ORF1a (blue), the RdRP in ORF1b (green), the capsid, spike and structural proteins in ORF2 (orange). A poly-A tail is encoded in the genome at the 3′ end.