We have developed a simple, fast, and efficient procedure to detect enteroviruses in water samples. Aliquots of water are subjected to two-step filtration, with the second filter containing a positively charged nylon membrane that holds back virus particles. Viruses thus adsorbed are directly lysed, and RNA is isolated by hybridization to specific oligonucleotides bound to magnetic beads. The solution used contains guanidine thiocyanate, which lyses virus particles, inactivates enzymes, e.g., RNases, allows mild hybridization conditions, and does not influence biotin-streptavidin interaction on magnetic beads. Detection and specific identification are accomplished by reverse transcription PCR of the highly conserved noncoding region at the 5 end of virus RNA combined with Southern hybridization. The system was tested with tap water artificially spiked with poliovirus vaccine and yielded a detection limit of 20 50% tissue culture infective doses per liter. We used the same procedure to investigate the water quality of surface water at public beaches by rivers and lakes. Of 40 samples tested, 7 were positive for enteroviruses. A comparison with enterobacterial contamination determined by PCR and classical microbiological methods in parallel showed that enteroviruses were found only in samples also positive for Escherichia coli. In conclusion, this procedure can easily be adapted to test large water samples and is simple enough to be used for routine determinations of water quality in terms of virus contamination. Enteroviruses are a major cause of gastrointestinal symptoms, colds, and fever, mainly in young children (11, 17, 23). In addition, they are recognized as an important factor in acute infections especially of the central nervous system, i.e., meningitis and encephalitis (11), and in subacute and chronic infections of the cardiovascular system, i.e., pericarditis, myocarditis, and cardiomyopathy (10, 24, 30), and they can lead to postviral fatigue syndrome (9). No clear correlation between enterovirus serotypes and specific symptoms has been determined (23). Enteroviruses are found worldwide. Infections occur by the fecal-oral route, and in most cases, treated surface water acts as the carrier of pathogens. Enteroviruses are highly stable in water (12, 19) and are not completely eliminated by sewage treatment plants (2, 12). Thus, the increasing use of treated surface water for drinking purposes harbors a potential source of pathogens which cannot be screened in a satisfactory manner. Classical methods of detection are based on inoculation of cell cultures, hatched eggs, or infant mice with test samples. Observations of cytopathic effect, hybridization with specific oligonucleotides, or reactions with antibodies indicate the presence of enteroviruses. These procedures are very laborious and time-consuming, though, and are not suitable for fast routine diagnosis. Besides, some serotypes either cannot be cultured or show no cell lysis. The use of DNA technologies has significantly improved the procedure to de...
