HONG KING – At Hong Kong’s desert airport, cleaners constantly spray baggage trolleys, elevator buttons and check-in counters with antimicrobial solutions. In New York City, workers constantly disinfect surfaces on buses and subways. In London, many pubs spent a lot of money on intensive surface cleaning to reopen after the lub pub down – before closing again in November.
All over the world, workers are soaping, wiping and smoking surfaces with an immediate sense of purpose: to fight the coronavirus. But scientists are increasingly saying that there is no evidence that contaminated surfaces can spread the virus. In crowded indoor spaces like airports, they say, viruses inhaled by infected people and surviving in the air are a big risk.
Washing hands with soap and water for 20 seconds – or sanitizer in the absence of soap – is still encouraged to prevent the spread of the virus. But scrubbing the surface will do little to reduce the risk of the virus, experts say, and health officials are being urged to focus on improving ventilation and indoor air purification.
“In my opinion, a lot of time, energy and money is being wasted on surface disinfection and, more importantly, attention and resources are being diverted from preventing airborne transmission,” said United’s respiratory infection specialist Dr. Dr. Kevin p. Said Fenelli. National Institutes of Health.
False sense of security
Some experts suggest that Hong Kong, a densely populated city of 7.5 million inhabitants and a long history of infectious disease outbreaks, is a case study of the type of operative surface cleaning that gives the general public a misconception about coronavirus.
The Hong Kong Airport Authority Authority has used a “full body disinfection channel” such as a phone-booth to make spirits of airport staff members in Kara Rentine areas. The booth – called the airport is the world’s first and is used exclusively by its employees – is part of an all-out effort to make the facility a “safe environment for all users.”
Such displays can be comforting to people as they show that local authorities are taking the fight to Covid-19. But Shelley Miller, an aerosols expert at the University of Colorado Boulder, said the booth made no practical sense from an infection-control standpoint.
The virus is excreted through activities that spray respiratory drops – talking, breathing, hoarseness, coughing, singing and sneezing. And disinfectant sprays are often made from toxic chemicals that can significantly affect indoor air quality and human health, said Dr. Miller.
“I don’t understand why anyone thinks that disinfecting an entire person would reduce the risk of contracting the virus,” he said.
‘Hygiene Theater’
A range of respiratory illnesses, including the common cold and influenza, are caused by microbes that spread from contaminated surfaces. So when the coronavirus outbreak caused winter in the mainland of China, it seemed logical to assume that these so-called foci were the primary means of spreading the pathogen.
Studies soon found that the virus persisted for up to three days on some surfaces, including plastic and steel. (Subsequent studies have shown that most of these are likely to be dead fragments of non-infected viruses.) The World Health Organization also emphasized surface transmission as a risk, saying airborne spread was a concern only when health care workers were engaged. In certain medical procedures that produce aerosols.
But scientific evidence was growing that the virus could stay in tiny drops in stagnant air for hours, infecting people with respiratory infections – especially inside crowded buildings with poorly ventilated ventilation.
In July, an article in the Lancet Medical Journal argued that some scientists had exaggerated the risk of superficial coronavirus infection, regardless of the study evidence of its close cousins, including the SARS-Covey, the driver of the 2002-03 SARS epidemic.
“This is extremely strong evidence that, at least for the original SARS virus, foamite transmission was largely negligible,” said Emanuel Goldman, a microbiologist at Rutgers University, author of the essay in an email. Referring to the new coronavirus, he added, “There is no reason to expect that a close relative, SARS-Cavi-2, would behave significantly differently in such an experiment.”
Dr. A few days after the publication of Goldm’s Lance Lance essay, more than 200 scientists called on the WHO to accept that coronavirus is transmitted by air in any indoor setting. Following tremendous public pressure on the issue, the agency acknowledged that indoor aerosol transmissions could cause indoor spaces with poor air circulation, such as restaurants, nightclubs, office fees and places of worship.
By October, the Centers for Disease Control and Prevention, which had maintained since May that the surface was “not the primary way to spread the virus”, said the transmission of infectious respiratory droplets was the “main mode” by which it operates.
But, by then, the paranoia about touching anything from handrails to grocery bags had taken off. And Covid’s tendency to blur surfaces as a precaution – what Atlantic Magazine calls it – was already deeply ingrained.
“My tennis partner and I stopped shaking hands at the end of the match – but, since I touched the tennis ball I’ve touched, what’s the matter?” Geoff Dyer wrote in a March essay for New Yorker Magazine that caught the germophobic zeitgeist.
Don’t interrupt
From Nairobi to Milan to Seoul, cleaners in hazmat suits are making a fuss in the public sphere despite warnings from the WHO that the chemical could do more harm than good.
In Hong Kong, where 299 people died during the original SARS epidemic, the elevator buttons are often covered in plastic that is cleaned several times a day. In some office fee buildings and subways, crew passengers clean the escalator handrail with disinfectant rags. Sweepers have exploded in public places with antimicrobial coatings and added a fleet of robots to clean surfaces in subway cars.
Many Hong Kong-based scientists insisted that cleaning could not harm cleaning, and supported the government’s strict social-distance rules and its month-long insistence on wearing near-universal masks.
Procter & Gamble said sales of its personal cleaning products grew more than 30 percent in the quarter ended September, with double-digit growth in every region of the world, including more than 20 percent in Greater China.
What about the air?
Hong Kong’s Covid-19 burden – more than 5,400 confirmed cases and 108 deaths – is relatively low for any city. Yet some experts say it has been slow in eliminating the risks of indoor aerosol transmission.
Initially, authorities required Hong Kong restaurants to install dividers between tables – a similarly trivial and essentially useless, defense U.S. No. Vice President’s debate in October.
But Hong Kong authorities have gradually eased restrictions on indoor gatherings, including allowing wedding parties of up to 50 people, so there are fears of a possible new outbreak inside the house.
Some experts say they are particularly concerned that coronavirus droplets could be spread by air raids in offices, which are crowded because the city has not yet developed a strong culture of remote work.
“People are wearing masks for lunch or when they come back to their cubicle because they believe their cubicle is their private space,” said Yang King-lun, a professor of chemical and biological engineering at Hong Kong Science and Technology.
“But remember: the air you breathe is basically communal.”
Mike Ives from Hong Kong and Apurva Mandavili from New York have reported.
