Antiviral activity of copper contact surfaces against MS2 coliphage and hepatitis A virus

Abstract

Aims: Viral diseases can be indirectly transmitted by contaminated non-food contact surfaces to final food products by cross-contamination. The interaction of metal surfaces and viruses, MS2 coliphage and hepatitis A virus (HAV), was investigated for strategy development in decreasing this transmission risk. Methods and results: MS2 deposited onto stainless-steel surface was stable but inactivated at 0.95 log10 PFU min−1 on 99.9% copper surfaces. Greater copper-inactivation of MS2 was observed in (a) simple media (phosphate buffered saline, PBS) than protein-rich media (beef extract buffer), and (b) acidic than pH ≥ 6.8 environments. Among food matrices (strawberry juices and beef broth), the greatest MS2 inactivation by copper occurred in filtered strawberry juice at pH 3.5. At a reduction of 0.17 log10 PFU min−1, HAV survived longer than MS2 on copper by FRhK-4 cell infectivity assay. Conclusions: The inactivation of virus on copper surfaces was greater in acidic viral surrounding environments and in simple PBS medium. In the same 99% PBS medium, MS2 may not be an appropriate surrogate for HAV when assessing viral inactivation on copper surfaces. Significance and impact of study In contrast to polymer, glass, and stainless-steel surfaces, copper inactivates enteric viruses upon direct contact, suggesting a potential interruption in disease transmission.