Norovirus cross-contamination during food handling and interruption of virus transfer by hand antisepsis: experiments with feline calicivirus as a surrogate.

While there is good epidemiological evidence for foods as vehicles for norovirus transmission, the precise means of spread and its control remain unknown. The feline calicivirus was used as a surrogate for noroviruses to study infectious virus transfer between hands and selected types of foods and environmental surfaces. Assessment of the potential of selected topicals in interrupting such virus transfer was also made.

A disc-based quantitative carrier test method to assess the virucidal activity of chemical germicides.

Suspension tests for virucidal activity of chemical germicides are easier to perform, but they normally do not present the test product with a strong enough challenge. In contrast, carrier tests, where the test virus is dried on an animate or inanimate surface, offer the test formulation a higher level of challenge because it first has to penetrate successfully the inoculum to gain access to and inactivate the target organism on the carrier. Since pathogens in nature are normally found adsorbed to surfaces and/or embedded in organic or cellular debris, the results of carrier tests are more relevant to predicting the activity of chemical germicides under field situations.

A feline kidney cell line-based plaque assay for feline calicivirus, a surrogate for Norwalk virus.

Feline calicivirus (FCV) has been used by researchers as a surrogate for Norwalk virus (NV), since they share a similar genomic organization, physicochemical characteristics, and are grouped in the same family, Caliciviridae. Unlike NV, however, FCV can grow in established cell lines and produce a syncytial form of cytopathic effect. In this report, we describe the development and standardization of a plaque assay for FCV using monolayers of an established line of feline kidney (CrFK) cells in 12-well cell culture plates.

Combined application of simulated reuse and quantitative carrier tests to assess high-level disinfection: experiments with an accelerated hydrogen peroxide-based formulation.

Background: Heat-sensitive medical devices require chemical disinfection between patients, and certain formulations for this purpose can be reused for several days. Because dilution, evaporation, and breakdown or neutralization of active ingredients can occur during reuse, it is vital to ensure that the solution retains its broad-spectrum germicidal activity even at the end of the recommended reuse period.

Objective: The purpose of this study was to combine the US Environmental Protection Agency's and the Food and Drug Administration's recommended simulated reuse method with recently developed quantitative carrier tests (QCT) to assess the broad-spectrum germicidal activity of a 7% solution of accelerated hydrogen peroxide (pH 2.