How do you tell the difference between an Asymptomatic Carrier & a Presymptomatic Carrier in your dental chair?

Question: How do you tell the difference between an Asymptomatic Carrier & a Presymptomatic Carrier in your dental chair?

Answer: You can’t!

The World Health Organization said what?!

I am absolutely floored by the WHO’s statement (on Monday June 8) that it is “very rare” for coronavirus to spread through asymptomatic carriers. What about all the information pointing to asymptomatic carriers as being a huge contributing factor to the spread of SARS-CoV-2? Something does not add up. 

As I dig a little deeper into what was said by the WHO I find that it is more of a misunderstanding than anything. I do not think that they were trying to purposely mislead the public. However, the statement was extremely misleading.

The WHO defines an asymptomatic carrier very strictly as someone who exhibits absolutely no symptoms whatsoever throughout the entire duration of their SARS-CoV-2 infection. The WHO is not including people with such minor symptoms that they do not report having “COVID symptoms,” such as a fever, cough or shortness of breath. Once taking these cases with extremely mild symptoms out of the mix, the WHO says that there are fewer asymptomatic patients than previously thought. So only a very small percentage of those infected are truly asymptomatic. According to the WHO, these truly asymptomatic patients rarely spread the disease. On the other hand, many patients contract the virus and are asymptomatic until they begin to have symptoms...these patients are not truly asymptomatic, they are simply pre-symptomatic. Presymptomatic patients can be and usually are contagious during their presymptomatic period. 

The important caveat for dentists is the difference between the apparently less threatening asymptomatic patients and the still infectious pre-symptomatic patients. So, how can you tell the difference? You cannot. There is no way to differentiate between asymptomatic and presymptomatic patients in your chair. As a dental practitioners we have to treat every patient as if they are infected and contagious. (Asymptomatic carriers are identified through contact tracing and testing.)

This statement from the WHO makes me realize more than ever that we, as dentists, are all responsible for using our education to make our own decisions on this pandemic. We all know how to read scientific research papers. We all know how to determine a legitimate case study. We are taught to be critical thinkers. This pandemic highlights exactly why we didn’t just “study teeth”, we had to learn microbiology, biochemistry, pharmacology...many times alongside the medical students at our schools. This is the time to use that education to make your own decisions about how to keep yourself, your families, your staff, and your patients safe. 

Practice Safely, 

-Allison Alexander, DMD


Listen to the WHO’s coronavirus press conference from June 8 here if you’re short on time, start at 31:30):