[Standardization of a method for concentration and detection of enteric viruses from drinking water]

Enteric viruses have been implicated in acute diarrheal disease, food-borne disease, hepatitis A and meningitis outbreaks, in which water was the vehicle of transmission.

A concentration method was standardized for the detection of enteric viruses in drinking water.

Twenty liters of water were concentrated to 6 ml by filtration and tangential ultrafiltration. Viral solutions of 20 L each were prepared at 1, 10, 50 and 100 TCID50 of Sabin poliovirus type 1 as positive controls. Viral particles were recovered by tissue culture and detected by conventional polymerase chain reaction (PCR), according to the international standards recommended by the Enterovirus Laboratory at the Centers for Disease Control and Prevention, Atlanta, GA.

All positive controls showed cytopathic effect on L20B and RD cells and were amplified by conventional PCR directly from samples. Negative controls did not show any amplification or viral cytopathic effect.

Tangential ultrafiltration for concentrating viruses proved to be a fast, efficient recovery and reproducible. It has the advantage of allowing the detection (at the 1 TCID50 level) and identification of viruses by RT-PCR and the demonstration of viral infectivity by tissue culture.