Hand-washing and disinfecting surfaces doesn't do much to curb the spread of respiratory viruses, because airborne transmission plays a much larger role, Jacob Stern wrote in an Oct. 24 piece for The Atlantic.
While the early days of the COVID-19 pandemic were marked by religious hand-washing and disinfecting of everything from groceries to doorknobs, scientists quickly learned airborne transmission was the primary mode of the virus's spread, not surfaces. Society then came to understand the value of mask-wearing, avoiding crowded indoor spaces and ventilation to prevent the spread of COVID-19. Many scientists now believe that same finding applies to most other common respiratory pathogens today, such as those that cause flu and the common cold.
Emanuel Goldman, PhD, a microbiologist at Rutgers New Jersey Medical School in Newark, believes nearly all respiratory pathogens are predominantly spread through the air, with surface transmission accounting for less than .01 percent of all infections. The reason there has instead been such a historical focus on surface transmission is because studies suggesting these theories were virus-survival studies, meaning they measured how long unrealistically large amounts of virus lived on a surface and didn't measure whether it remained infectious, he told The Atlantic.
Many infectious disease experts now agree transmission via surfaces or objects plays an insignificant role in the spread of respiratory viruses, but it may pose more of a risk in certain settings, such as daycares. Simply put, different settings may require different infection-prevention strategies.
"Frequently disinfecting a table in a preschool classroom might make a lot of sense; frequently disinfecting the desk in your own private cubicle, less so," Mr. Stern writes.
The takeaway message from experts: Precautions taken to prevent surface transmission shouldn't come at the expense of efforts to protect against airborne transmission.
"If you're doing extra hand washing … then you should also be wearing a good mask in crowded indoor environments," Linsey Marr, PhD, environmental engineer and aerosols expert at Blacksburg-based Virginia Tech, told The Atlantic. "If you're bothering to clean the surfaces, then you should be bothering to clean the air."