Do This Simple Test and Your Covid-19 Nose Culture Will Be Much Less Painful (+Accurate!)
False-negative results tests for Covid-19 can be the result of inadequate sampling. New studies tell us that the Covid-19 virus replicates in the postnasal region called nasopharynx. Not inserting the swab deeply enough, results in sampling the less deep, intermediate (turbinate part of the nasal cavity), not from the posterior nasopharynx where the virus lives.
It’s entirely normal to jerk back when a swab is being poked a scary depth. Sampling is normally done by inserting the culture stick sequentially through both nostrils and turbinates before reaching the nasopharynx, which is at an imaginary line between your two ears. Surprisingly, no matter which side is sampled, the same anatomic area is reached.
For some people, one side of the nose is somewhat narrower because of the cartilage and bone curvature in the nose. In addition, a physiological reflex called “nasal cycling,” causes the soft tissue called the lower turbinate in the nasal cavity to change in size, even in people with undeviated nasal septums. Turbinates are triple-tiered, mid-depth, nasal soft tissue, canoe-shaped structures which cyclically expand and contract over a period of hours. One turbinate enlarges while the other contracts.
Although we don’t normally feel any nasal obstruction, the air passing through both nostrils and the inner width of the nasal passages equalize due to synchronization of nasal cycling. (The picture above shows a normal occurrence.)
Due to another relatively common condition, septal deviation, everyone prior to sampling should be asked about which nostril he/she can breathe more easily.
Do this simple self-test. First gently press and block one nostril while breathing through the other open nostril. Release and test the other side in the same way. Only you know which side is more free-flowing. Upon discovering the more open and favorable side, tell your healthcare provider to to sample that side — first!
To repeat, the swab should be inserted into the side you find breathing more easy. By reaching the nasopharynx easily through the more open side and rotating the culture swab enough there, can diagnostic material can be assured to reach the lab. Any subsequent attempt getting a culture from the other, narrower side of the nose will be less consequence. Enough material from the first side will likely be sufficient for you to have a reliable test and avoid a repeat insertion because you couldn’t suppress a cough.
By following this simple self-test, your viral test result will likely be more accurate and less uncomfortable, because you now know how to get the best chance on the very first pass. Pass it on and save your friends misery!
