Concentration of Seeded and Naturally Occurring Enteroviruses from Waters of Varying Quality by Hollow Fiber Ultrafiltration

A semi-automated hollow fiber ultrafiltration system was used to concentrate viruses from tap water, river water and treated and untreated wastewater. Samples were dehydrated by filtration through an asymmetric polysulfone hollow fiber module with a molecular weight cut-off of 10,000 D. Retained solute was recovered from the filter by backwashing with water, buffer and other solutions. One hundred liters of tap water seeded with poliovirus type 2 Sabin were processed in 161 ± 22 minutes (average flux 1.2 ± 0.1 × 10−3 cm/sec). Retained virus was recovered from the filter by backwashing with 150 ml of 0.05 M glycine, pH 10.0, which was further reduced to about 10 ml by the organic flocculation technique. Average recovery of 60 plaque-forming units (PFU) of poliovirus from 100 1 of tapwater was 148 ± 10%. Hudson River water (100 1 with an average turbidity of 3.2 NTU) was processed in 218 ± 34 minutes (average flux 0.8 ± 0.2 × 10−3 cm/sec). Recovery of 114 PFU of poliovirus seeded into 99 1 of river water was 35%. No natural virus was recovered from unseeded river water. Naturally occurring viruses, tentatively identified as echovirus type 14, coxsackie virus type A9 and coxsackie virus types B2-B5, were isolated from concentrates qf treated and untreated wastewater (average fluxes 0.58 × 10−3 and 0.46 × 10−3 cm/sec, respectively).