Application of PCR-based methods to assess the infectivity of enteric viruses in environmental samples

The advent of the PCR has greatly enhanced our ability to detect human enteric viral pathogens in the environment, including water, municipal wastes, sewage, food, air, and fomites (2, 3, 59, 69, 79). This is especially true for those viruses which do not grow in cell culture. Despite great sensitivity, PCR methods do have some serious limitations for environmental viral analysis, including small sample volumes, the presence of PCR-inhibitory substances, and an inability to differentiate between infective and noninfective viruses (66). The ability of PCR to assess infectivity would greatly enhance its application for the monitoring of water and food quality and for treatment processes (e.g., disinfection). This review focuses on approaches to overcome these limitations.