As China struggles with its largest increase in covid cases, the government’s decision to continue to push the narrative that surfaces pose a significant risk of infection means that time and money are being spent on the wrong things during a crisis, scientists say. Measures to stop air transmission are much more effective.
The policy of prioritizing disinfection is part of a broader state-controlled narrative that politicizes the health crisis and is designed to legitimize the government’s response. It also plays with China’s favorite narrative about the origins of covid: that it could have been imported into Wuhan using frozen foods.
Divergent pandemic paths
The scientific debate over how much surface area contributes to the spread of covid is almost over internationally. For example, a study from the University of Michigan, published in April 2022 in the Journal of Exposure Science & Environmental Epidemiology, estimated that the chance of trapping covid from a contaminated surface is 1 in 100,000, very below the benchmark suggested by the researchers as tolerable. risk
And while the risk is not zero, the vast majority of public health agencies, including the World Health Organization, have found it too low to warrant active action other than recommending handwashing. Outside of China, most countries have long since stopped encouraging people to disinfect things as a way to prevent covid. The U.S. Centers for Disease Control and Prevention updated its guide two years ago, in May 2020, to reflect the fact that it is mostly unnecessary.
In contrast, the overwhelming consensus is that aerosols and droplets transmit the virus much more easily than surfaces. In fact, the same Michigan study in April 2022 found that airborne transmission is 1,000 times more likely than surface transmission.
“People only have the bandwidth to do so many health-protecting behaviors. It’s ideal that they focus on the things that will have the greatest impact on reducing their risk,” says Amy Pickering, an assistant professor at environmental engineering at the University of California, Berkeley. “And that would be wearing masks, social distancing, avoiding crowded interior spaces.”
The media and the Chinese government often point to investigations to justify the continued fear of superficial transmission. Studies conducted by researchers in Hong Kong, Japan and Australia have found that covid viruses can survive for days or weeks on various surfaces.
But many have not been peer-reviewed, and yet these lab results do not reflect real life, says Ana K. Pitol, a postdoctoral researcher at the Liverpool School of Tropical Medicine in the United Kingdom. “If you put a huge drop in a medium that protects the virus, and you put it in a container and put it in an incubator, of course, it will survive for many days, sometimes even weeks,” he says. “But the question we should ask ourselves is how long do you survive in a realistic situation.”