Resembling a mini electric fan, an ultraviolet disinfection device that is able to achieve 99.9 percent sterilization, including killing the COVID-19 virus, helped keep Team China free of infections at the Tokyo 2020 Olympic Games.

An advantage of the device is that it can work in a human environment in real time, said Shanghai's Fudan University, one of its developers.

The equipment helped the 777 members of Team China to eliminate microorganisms, including viruses and bacteria, from the air and surfaces.

More than 200 of the devices played their role in providing a safe environment for the athletes, coaches and other workers, in their exercise venues as well as the athletes' bedrooms.

Wu Fan, vice-dean of Fudan University's Shanghai Medical College, explained that the device uses short-wavelength ultraviolet light technology. The device can emit a 222-nanometer wavelength that is absorbed by the novel coronavirus. The helical structural link of the ribonucleic acid of the virus is destroyed and the virus loses its ability to replicate, Wu said.

"As the short wavelength of 222 nanometers won't penetrate human skin and eyes, it is harmless to the human body and can work when people are around," said Wu, who is also director of the Shanghai Municipal Institute of Major Infectious Diseases and Biosafety.

She added that people cannot feel anything when the device is in operation and it does not generate any harmful substances or chemical residue.

"The coexistence of people and disinfecting machines in the same environment with the machines working in real time is actually a thorny problem. This device conquers it," Wu said.

All viruses, bacteria and fungi can be killed by irradiation with a specific wavelength, according to experts.

Columbia University in the United States, Fudan University, the Shanghai Municipal Institute of Major Infectious Diseases and Biosafety and Lumenlabs, a Shanghai-based enterprise dedicated to creating sanitation solutions with shortwave ultraviolet, jointly developed the equipment.

The devices, which are able to kill the COVID-19 virus at temperatures above 4 C, have also been sent to hospitals in Zhengzhou, Henan province, to provide doctors and nurses with a safer environment in the fight against the novel corona-virus, according to Fudan University.

"Our ultimate goal is that the equipment will be popularized for civil use. The machine will show its advantage in public venues with high population density, such as medical institutions, nursing homes for the elderly, transportation hubs and commercial centers," said Wu.

"Traditional ultraviolet light disinfectors used in medical institutions can only operate when nobody is around, while this technology allows the new devices to work continuously in high-risk venues, such as fever clinics," she said.

The limitation of the new device is that it cannot disinfect places where light cannot reach, such as the back of an object, according to the developers.