Survival and Transport of Enteric Viruses in the Environment

Abstract

Environmental virology may be defined as the study of viruses that can be transmitted through various environments (water, sewage, soil, air, or sur- faces) or food and persist enough in these vehicles to represent a health threat.A wide variety of different viruses, representing most of the families of animal viruses, can be present in human and animal fecal wastes and urine. Especially important are a variety of nonenveloped human and animal enteric pathogenic viruses that can enter the environment through the dis- charge of waste materials from infected individuals; contaminate food products and drinking and recreational waters; and be transmitted back to susceptible individuals to continue the cycle of infection (Table 6.1). It is esti- mated that billions of cases of gastrointestinal illness occur annually world- wide (Parashar et al., 1998; Oh et al., 2003).A good deal of these diarrheal cases are to some extent the result of fecal contamination of the environ- ment (Cabelli et al., 1982; Koopman et al., 1982; Fattal and Shuval, 1989; Moore et al., 1994) while outbreaks of hepatitis A and E are associated with water, shellfish, and crops (Melnick, 1957; Reid and Robinson, 1987; Halliday et al., 1991; Bosch et al., 1991, 2001).