In this paper we report the results of an investigation into the presence of enteric viruses in shellfish from the waters around Sardinia. Twenty two samples of shellfish were examined using a rapid and sensitive technique to concentrate and detect viral RNA in shellfish tissues. After recovery of viral particles, RNA was extracted, transcribed into cDNA and amplified using "nested PCR". Testing with enterovirus-specific RT-PCR produced positive results in over 13% of specimens. The virus detection procedure appears to be effective. In some circumstances it could be a better test of water quality than conventional monitoring techniques.