Every time during season transition, when day and night temperature difference becomes greater, people are more likely to catch a cold; and during these times we often see and hear more sneezing from people around us. We all sneeze, but what’s so special about this small, simple, and natural body reaction that needs our attention?
We all have different experience with sneezing. Some patients complain that they felt like their ears are stuffed and can’t hear well after sneezing; some people felt headache after sneezing; some people nose bleed after sneezing; some people complain that people sneeze at him which caused him to catch a cold too.
Sneezing is our body’s natural self-defence reaction. When our nasal cavity is irritated by the foreign particles such as dirt, virus or cold air, our nose uses this “sneeze” action to propel with strong airflow to get rid of these undesirables from our nasal cavity mucus. Clinical study has shown that the sneezed secretions from people with respiratory infections have high virus concentration, so there’s absolutely no need to try to suppress a sneeze. Besides, most of the time sneeze cannot be controlled.
Medical study has pointed out that the per unit airflow speed inside our nasal cavity during a sneeze is on par with a typhoon or hurricane, so there is quite a high air pressure built up inside there. That is why during a sneeze it is better to have your mouth open and not to pinch your nose to provide a channel for this strong airflow to exit easily. However, if you have your mouth shut and nose pinched, this great air pressure will then be forced towards middle ear via Eustachian tube, this will make you feel like there’s something blocking your ear (similar to when there’s water in ear); in a more serious case, this air pressure could rip and damage the ear drum. Nasal cavity mucus layer would also be damaged and swell, or if there was recently healed wound from a nose bleed, the strong turbulence could reopen up the wound. If the thick mucus is pushed into the middle ear, then it could cause acute otitis media; if the thick mucus ended up in paranasal sinus, then it could cause acute nasosinusitis. So it is extremely important to have your mouth and nostril open up to allow this nasal hurricane to exit freely.
Main reason why some people like to pinch their nose during a sneeze is to not only reduce the sneezing sound, but also to prevent the mucus from spurting onto other people. But if pinching our nose during a sneeze could cause great damage to our middle ear and or paranasal sinus, what should we do then? Traditionally, we were always told to face away from food or other people during a sneeze, and cover our mouth and nose with hand to prevent the spreading of germs. After the global threatening SARS event, public health experts have re-examined the prevention of respiratory disease, and suggested that instead of using our hand to cover a sneeze or cough, it is much better to cover with the upper sleeve of our clothes; even though yes it’s true that the germ would get onto our clothes. The reason is because the two main transmitting pathways for respiratory disease are through direct air transmitting or touch transmitting. Direct air transmitting can be more easily prevented by blocking or avoiding the source, but touch transmitting is much harder to prevent. When blocking with our hand, unless we wash our hand with soap immediately after, germs can be easily transmitted to any object touched by our hands and become the next transmitting source; anyone who touches these objects with their hand and then rub their eyes or pick their nose would be easily infected. This is why during SARS period, solely rely on N95 mask was not enough to prevent the spread. So next time you sneeze or cough, remember to use a upper sleeve to block instead of using bare hand; or if hand was used, remember to wash your hand immediately with soap.
Dr. T