“CDC has determined that the risk of transmission to the surface is low, and secondary to the primary routes of virus transmission through direct contact droplets and aerosols,” said Vincent Hill, head of the Water Disease Prevention Branch, on a CDC-sponsored telephony briefing.
Hill said the risk of transmission by touching a surface, though small, was increased indoors. Outside, the sun and other factors can destroy viruses, Hill said.
The virus dies “quickly” on porous surfaces, but can persist longer on hard indoor surfaces.
Research also suggested that surface transfer was more likely in the first 24 hours after a person was infected, and that households where one person had Covid-19 had lower transmission rates when the household cleaned and disinfected surfaces.
“In most situations, cleaning surfaces with soap or detergent, and not disinfecting them, is enough to reduce the already low risk of virus transmission through surfaces,” Hill said. “Disinfection of surfaces is usually not necessary unless a sick person or someone positive for Covid-19 has been in the home for the past 24 hours.”
Hill said the cleanup should focus on high-contact areas such as door knobs and light switches.
Household cleaners pose a danger
People use household cleaners to protect themselves from Covid-19, but abuse can have dangerous consequences, Hill added.
Regular cleaning and disinfection of surfaces can have a minimal impact on the transmission of viral and can contribute to the “hygiene theater”, he added.
Holding a show “to clean and disinfect” can be used to give people a sense of security that they are protected from the virus, but it can be a false sense of security if other preventative measures such as the wearing masks, physical distance, and hand hygiene are not performed consistently, ”Hill said.
“It can also make people feel less needed to get involved in these other important preventative measures.”
Additional data show that the disinfectants themselves may pose a risk.
“Public inquiries suggest that some people can deliberately drink, inhale or spray their skin with disinfectants, without understanding that the use of disinfectants in this way can cause serious damage to their bodies,” he said.
Hill cited CDC research from June 2020, showing that only 58% of people surveyed knew that bleach should not be mixed with ammonia, because mixing bleach and ammonia creates a toxic gas that infects people’s lungs. impair.
And bleach itself can be harmful.
“Nineteen percent were food products with bleach, which can lead to the consumption of bleach that is not washed off, which can damage the body because bleach is toxic. Eighteen percent use household cleansers on bare skin, which can damage the skin and cause rashes and burns, ”Hill said.
Hill added that surveillance data show that the number of disinfectant calls in 2020 for disinfectants was higher than in 2018 or 2019.
Alternative disinfection methods can also be a waste of time or even risky, says the CDC in the updated guidance.
“The effectiveness of alternative surface disinfection methods, such as ultrasonic waves, high intensity UV radiation and LED blue light against the virus that causes COVID-19, has not yet been determined,” the CDC said on its updated website.