New copper surface eliminates bacteria in just two minutes

A new surface that kills bacteria more than 100 times faster and more effectively than standard copper could help combat the growing threat of antibiotic-resistant superbugs. The new copper product is the result of a collaborative research project with RMIT University and Australia’s national science agency, CSIRO, with findings just published in Biomaterials. Copper has long been used to fight different strains of bacteria, including the commonly found golden staph, because the ions released from the metal’s surface are toxic to bacterial cells. But this process is slow when standard copper is used, as RMIT University’s Distinguished Professor Ma Qian explained, and significant efforts are underway by researchers worldwide to speed it up.

The copper magnified 500,000 times under a scanning electron microscope shows the tiny nano-scale pores in the structure

A standard copper surface will kill about 97% of golden staph within four hours,” Qian said. “Incredibly, when we placed golden staph bacteria on our specially-designed copper surface, it destroyed more than 99.99% of the cells in just two minutes.” “So not only is it more effective, it’s 120 times faster.” Importantly, said Qian, these results were achieved without the assistance of any drug. “Our copper structure has shown itself to be remarkably potent for such a common material,” he said.

The team believes there could be a huge range of applications for the new material once further developed, including antimicrobial doorhandles and other touch surfaces in schools, hospitals, homes and public transport, as well as filters in antimicrobial respirators or air ventilation systems, and in face masks. The team is now looking to investigate the enhanced copper’s effectiveness against SARS-COV-2, the virus that causes COVID-19, including assessing 3D-printed samples. Other studies suggest copper may be highly effective against the virus, leading the US Environmental Protection Agency to officially approve copper surfaces for antiviral uses earlier this year.

Source: https://www.rmit.edu.au/news/

The Coronavirus Is Airborne

The coronavirus is finding new victims worldwide, in bars and restaurants, offices, markets and casinos, giving rise to frightening clusters of infection that increasingly confirm what many scientists have been saying for months: The virus lingers in the air indoors, infecting those nearby.

If airborne transmission is a significant factor in the pandemic, especially in crowded spaces with poor ventilation, the consequences for containment will be significant. Masks may be needed indoors, even in socially-distant settings. Health care workers may need N95 masks that filter out even the smallest respiratory droplets as they care for coronavirus patients.

Ventilation systems in schools, nursing homes, residences and businesses may need to minimize recirculating air and add powerful new filters. Ultraviolet lights may be needed to kill viral particles floating in tiny droplets indoors.

The World Health Organization (W.H.O.) has long held that the coronavirus is spread primarily by large respiratory droplets that, once expelled by infected people in coughs and sneezes, fall quickly to the floor. But in an open letter to the W.H.O., 239 scientists in 32 countries have outlined the evidence showing that smaller particles can infect people, and are calling for the agency to revise its recommendations. The researchers plan to publish their letter in a scientific journal next week. Even in its latest update on the coronavirus, released June 29, the W.H.O. said airborne transmission of the virus is possible only after medical procedures that produce aerosols, or droplets smaller than 5 microns. (A micron is equal to one millionth of a meter.)

Proper ventilation and N95 masks are of concern only in those circumstances, according to the W.H.O. Instead, its infection control guidance, before and during this pandemic, has heavily promoted the importance of handwashing as a primary prevention strategy, even though there is limited evidence for transmission of the virus from surfaces. (The Centers for Disease Control and Prevention now says surfaces are likely to play only a minor role.)

Dr. Benedetta Allegranzi, the W.H.O.’s technical lead on infection control, said the evidence for the virus spreading by air was unconvincing.

Source: https://www.nytimes.com/