CALICIVIRUS EMERGENCE FROM OCEAN RESERVOIRS - ZOONOTIC AND INTERSPECIES MOVEMENTS

Caliciviral infections in humans, among the most common causes of vira l-induced vomiting and diarrhea, are caused by the Norwalk group of sm all round structured viruses, the Sapporo caliciviruses, and the hepat itis E agent. Human caliciviruses have been resistant to in vitro cult ivation, and direct study of their origins and reservoirs outside infe cted humans or water and foods (such as shellfish contaminated with hu man sewage) has been difficult. Modes of transmission, other than dire ct fecal-oral routes, are not well understood. In contrast, animal vir uses found in ocean reservoirs, which make up a second calicivirus gro up, can be cultivated in vitro. These viruses can emerge and infect te rrestrial hosts, including humans. This article reviews the history of animal caliciviruses, their eventual recognition as zoonotic agents, and their potential usefulness as a predictive model for noncultivatab le human and other animal caliciviruses (e.g., those seen in associati on with rabbit hemorrhagic disease).