Study: Hepatitis E virus defies alcohol-based hand disinfectants

 Hepatitis E is an inflammation of the liver caused by infection with the hepatitis E virus (HEV). HEV is the most common cause of acute virus-mediated hepatitis worldwide. Even though the infection can be prevented through appropriate hygiene measures, a recent study revealed that common hand disinfectants did not inactivate the virus.

The study was published in the 'Journal of Hepatology'.

Scientists from TWINCORE, Centre for Experimental and Clinical Infection Research, the Hannover Medical School (MHH) and the Ruhr Universitat Bochum (RUB), together with partners from industry, investigated the effectiveness of various common hand disinfectants against HEV. They were able to show that most formulations did not completely inactivate the virus.

In Germany and Europe, HEV has its natural reservoir in pigs. The infection can spread from animals to humans, which is called zoonosis. This often happened through incompletely heated or raw meat products such as minced meat. In tropical regions of the world, infections occur via contaminated water, sometimes causing large outbreaks.

"Some of these infections could possibly be prevented with the right hygiene measures," said Dr Patrick Behrendt, physician in the Department of Gastroenterology, Hepatology and Endocrinology at the MHH and head of the junior research group "Translational Virology" at TWINCORE. This included, above all, correct hygienic hand disinfection in everyday clinical practice when dealing with hepatitis E patients and infected animals.

Together with the team of Professor Eike Steinmann, head of the Department of Molecular and Medical Virology at RUB, Behrendt investigated whether common hand disinfectants can render the virus harmless. "We tested the effect of the alcohols ethanol and propanol, both individually and in the mixing ratios recommended by the WHO, and also commercial hand disinfectants," said Steinmann. "However, only one product that contained another component was effective."

Normally, HEV occurs non-enveloped and, like all non-enveloped viruses, is very resistant to chemical influences. However, virus particles circulating in the blood of patients are surrounded by a lipid envelope. "Not all disinfectants are effective against enveloped and non-enveloped viruses at the same time," said Steinmann. "We used both forms of HEV for our tests."

Although some of the disinfectants tested were certified to inactivate both enveloped and non-enveloped viruses, they were not sufficiently effective against HEV. "The alcoholic components dissolve the lipid envelope, but the resulting "naked" viruses are still infectious," said Behrendt. So HEV is literally hard to break down. The decisive advantage was a product that contains phosphoric acid as well as alcohol. This neutralised all the virus particles sufficiently.

"We were able to show that HEV can resist most common hand disinfectants," said Behrendt. "We hope that these findings will be taken into consideration in the future when hygiene measures are recommended for handling contaminated meat products and in HEV outbreak situations."