Recovery tests of cytopathogenic viruses from artificiallycontaminated food samples

Abstract The artificial contamination tests were carried out by using a Coxsackie B5 virus of known titration to contaminate vegetable food products (lettuce and berries). The experimental protocol was divided basically into two phases: elution with alkaline pH buffer solution and following concentration of viral particles recovered by using PEG8000 (polyethylene glycol). A third phase of purification with chloroform was introduced between these two steps in order to assess its effect on the yield of the final recovery, and tests were performed in parallel with both the protocols to compare them in terms of recovery efficiency. Elution phase proved to be the most critical, since the viral recovery from food samples during this phase resulted moderate (2.95% and 2.16% respectively in tests without and with chloroform purification phase), data already observed in previous studies. The final concentration phase with PEG8000 recorded average recoveries equalling 0.29% in tests without chloroform and equalling 3.97% in tests with purification phase, thus showing a significant improvement with a lesser interference by the organic material.