Is There Asymptomatic Spread of COVID-19? Depends WHO You Ask!
Updated: Oct 20, 2020
VP of Medical, K Health
“Asymptomatic spread” of COVID-19 is the concept that the disease can be spread by an infected person who isn’t actively exhibiting symptoms. This is a very important concept, because asymptomatic spread is one of the main reasons that much of our country (and much of the world!) has been in lockdown, as it would be impossible to know who is an asymptomatic spreader of COVID-19 without widespread testing and the ability to track and trace the people who had been exposed. Understanding asymptomatic spread is also critical to forecasting disease spread and driving public policy measures.
Unsurprisingly, it was big news when officials from the World Health Organization (WHO) suggested that COVID-19 patients without symptoms do not contribute significantly to the spread of the illness.
In particular, the WHO’s head of emerging diseases and zoonosis, Dr. Maria Van Kerkhove, said, “From the data we have, it still seems to be rare that an asymptomatic person actually transmits onward to a secondary individual.” These comments were particularly surprising because it was previously felt that a significant portion of disease spread is due to these asymptomatic patients. However, since that initial statement, the WHO has walked back their comment, acknowledging that when it comes to asymptomatic spread, “we don’t actually have that answer yet.”
So, what are the real facts and what do we actually know about asymptomatic spread of COVID-19? Unfortunately, there are a lot of unanswered questions. We know that some models estimate that 40% of transmission may be due to asymptomatic infected patients but that's about it. Until we have more complete data that can provide us better answers around this disease, it's better to play it safe. We recommend that as you start to leave your home to return to work and other activities, you should still wear a mask and focus on simple but important techniques like frequent hand washing with soap and water.
Photo by Thomas de LUZE