Antimicrobial surface coating kills coronavirus for 90 days

A specially formulated antimicrobial coating can keep surfaces clear of a human coronavirus for up to 90 days with just one application, a preliminary study said, suggesting a new line of defence against COVID-19.

The paper by researchers at the University of Arizona (UA), which has not yet been peer-reviewed, found that the amount of virus on coated surfaces reduced by 90% in 10 minutes and by 99.9% in two hours. Charles Gerba, a microbiologist at UA who was the study’s senior author, said the technology was “the next advancement in infection control.” “I think it’s mostly important for high-use surfaces like subways and buses, because you could disinfect them but then the next people that come in there will re-contaminate the surfaces,” he said.

“It’s not a substitute for regular cleaning and disinfecting, but it covers you in between regular disinfecting and cleaning.” The UA team tested a coating specifically designed to act against viruses that was developed by the company Allied BioScience, which also funded their study. The researchers carried out their testing on human coronavirus 229E, which is similar in structure and genetics to SARS-CoV-2 but causes only mild cold symptoms and was therefore safer to use.

The coating works by “denaturing” the virus’ proteins — effectively twisting them out of shape — and attacking its protective layer of fat.

The colourless substance is sprayed on surfaces, and has to be reapplied every three to four months. The technology behind so-called self-disinfecting coatings has been around for almost a decade, and has been used in hospitals to fight against the spread of infection, including against antibiotic-resistant bacteria.