The Detection of Enteroviruses in Water and Associated Materials Using the Polymerase Chain Reaction

Abstract

The environment furnishes a variety of surroundings that may favor the survival of microorganisms. The aquatic environment (which includes marine and fresh water, raw and treated sewage, sludge, and sediments) often provides conditions in which pathogenic viruses released from the body may retain infectivity and cause disease on entry into a new host. Enteric viruses shed from the gut in feces will be transported into the sewerage system and may end up in water used for drinking water abstraction or recreation (1). Enteroviruses, which include vaccine-derived poliovirus, can readily be isolated using cell culture and have therefore been shown to be abundant in raw sewage. Detection of any of the other enteric virus groups is less practical as techniques are more difficult or not available. Even the procedure for enteroviruses, used in many studies of the environment, is laborious, expensive, and slow to produce results. Although not a cause of gastroenteritis, enteroviruses may cause disease including paralysis, meningitis, myocarditis, and cardiomyopathy, and less severe infections, such as, colds and fever, mainly in young children, They are therefore a public health concern, and in order to make proper evaluation of their significance, in water techniques are required that are rapid and reliable and can accommodate large numbers of samples in one test batch. It should then be possible to process the number of samples required to make proper risk assessments (2,3). Further, detection of enteroviruses will demonstrate the presence of sewage and therefore by implication the potential presence of other enteric viruses, such as small, round-structured viruses (Norwalk-like viruses), which do cause gastroenteritis. The European Union (EU) recognizes the detection of enteroviruses in bathing waters as a parameter in its Bathing Waters Directive (4) and though this currently requires enterovirus detection by infectivity assay, the use of a rapid test to screen out negative samples prior to analysis for infectious virus by cell culture makes the testing process more efficient in time and cost.