'Cold plasma' kills off norovirus
Norovirus, the most common cause of gastroenteritis in the world, can be killed with "cold plasma," researchers in Germany said, the BBC reports.
The virus, which elicits vomiting and diarrhea, has gained international notoriety for causing outbreaks on cruise ships.
However, such incidents represent merely a fraction of the tens of millions of cases that occur around the world each year.
The research appears in mBio journal.
Preventing norovirus outbreaks is complicated by the fact that the virus is highly resistant to several different chemical disinfectants.
Bleach, a chlorine-based solution, is currently the most effective treatment, but researchers are seeking more convenient alternatives.
One such alternative is cold plasma, also known as non-thermal plasma. This "fourth state of matter" consists of ionized gas molecules at room temperature. These ions can destroy many kinds of microbes, but their effect on viruses was less clear.
A team of scientists led by Dr Birte Ahlfeld and Prof Günter Klein at the University of Veterinary Medicine in Hannover examined the effect of cold plasma on a strain of norovirus isolated from a human faecal sample taken during an outbreak at a military base in Germany.
Cold plasma treatment led to a roughly 20- to 50-fold reduction in the number of virus particles.
The viruses were destroyed because cold plasma consists of highly noxious ions, called reactive nitrogen and oxygen species, which exhibit potent antimicrobial activity.
Moreover, the cold plasma generator, which produces the ions by applying an electric field to ambient air, could be designed as a handheld device. Alternatively, commonly contaminated surfaces, such as salad bars, could have cold plasma generators built into them.
"A spread of norovirus can be inhibited at crucial points, which as we know from our previous studies are all surfaces with frequent contact to human skin or hands," Dr Klein said.
"Handheld devices can be used to disinfect different surfaces or a plasma box for hands or cutlery or plates is possible."