Bacterial Indicators of Viruses

Abstract

The association between human enteric viruses and disease is well established. However, determining the presence of all of the many types of viruses that are pathogenic to humans in food and water is not practical at this time. Because enteric bacteria are usual inhabitants of the human intestinal tract, they have been used as indicators of fecal pollution and the possible presence of enteric viruses. Several different types of bacteria have been considered for use as indicators. Currently, most tests for indicator microorganisms rely on the detection of lactose-fermenting bacteria (coliforms, fecal coliforms, E. coli). Food and water samples with relatively high levels of these bacteria have frequently been found to contain bacterial and viral pathogens. However, viral pathogens have also been found in food and water samples with no or acceptable levels of indicator bacteria. It may be necessary to supplement tests for bacterial indicators with tests for other indicators, such as bacteriophages (see Chapter 8). Also, it may be desirable to determine the source of indicators, at least to the extent of determining if they are from human or non-human sources. This may lead to a better correlation between the presence of human indicator bacteria and human enteric viruses.