Emerging food-borne viral diseases.

Severe acute respiratory syndrome (SARS) virus, avian influenza virus, and Nipah virus are examples of viruses for which food-borne transmission was not considered immediately but that illustrate the potential and the difficulty in assessing the potential for food-borne transmission. This chapter focuses on the basic information that has been gathered on the pathogens from the perspective of food safety. In this chapter, viruses are considered emerging pathogens if their incidence has increased within the past two decades or threatens to increase in the near future. The chapter provides an overview of taxonomic groupings of mammalian viruses, their zoonotic potential, and an assessment of their theoretical (or reported) potential for food-borne transmission based on virus properties. It also focuses on the other virus families: Birnaviridae, Circoviridae, Papillomaviridae, Parvoviridae, and Polyomaviridae. The virus families were selected based on viral characteristics that would make them candidates for food-borne transmission. For SARS coronavirus (CoV), two food-related transmission routes should be considered. The first is the direct zoonotic food-borne transmission by consumption of any of the nonhuman hosts of the virus. The other route is food handler transmission. In addition, however, this chapter presents a number of examples of viruses that would be considered unlikely candidates for food-borne transmission based on their physical characteristics but still were reported to be food borne, such as avian influenza (AI) and Nipah viruses.