Concentration of Viruses in Faecal Samples from Patients with Gastroenteritis

Faecal samples from 100 patients with gastroenteritis were examined by three methods; a) fluid absorption with polyacrylamide hydrogel, b) ammonium sulphate precipitation and c) ultracentrifugation to compare the concentration of virus particles before examination by negative stain electron microscopy. By all three methods, a similar content and range of viruses were detected, but the hydrogel technique presented some distinct advantages. Factors influencing fluid absorption from faecal extracts are outlined.