A Sinus Infection Contagious?

The short answer, no, sinus infections are not contagious.  Many people seem to stick with this general idea thanks to the name sinus infection, when this medical condition is not really an infection at all.  

As a medical term, a sinus infection is actually just a constant state of inflammation in the sinus cavities and other nasal passageways.  When we breath, we inhale a number of different things.

  Everything from pollutants to dust to animal dander goes into our nose, and therefore into our sinuses.  These particles tend to become trapped in the mucus held in the nasal passageways and the sinuses, resulting in the irritation of the lining of these delicate membranes.  Once they have become irritated, they become inflamed through the release of histamine.

  This histamine is used to counteract the irritation, but it results in the inflammation of the sinus pathways.  As a result of this, the body produces more mucus, causing the sinuses to become clogged.  This is what we commonly know as a sinus infection.  Notice, there is not real infection involved, it just a series of reactions that cause excess mucus that causes an irritating and clogging of the sinuses.

This means a sinus infection is not contagious.  There are other aspects of this medical condition that has lead many people to think that they are.  For one, the common cold is contagious.  Many sinus infections start as the result of other medical condition.  Things like the common cold can help to cause the overproduction of mucus in the sinuses. 

 The resulting build-up of extra mucus can lead the sinuses to become clogged.  While the sinus infection itself was not spread from person to person, the condition that caused it to develop can be spread from person to person. 

Viruses are also a common cause of sinus infections, and share a similar story to that of the common cold.  Viral infections, especially influenza, can help to prevent the sinuses from draining by immobilizing the cilia, the parts of the body that help the sinuses to drain.  

Once these are immobilized and rendered useless for a period of time, the mucus will build up, resulting in a sinus infection.  While the sinus infection is not the contagious element, the direct cause of the sinus infection, the virus, can easily spread from person to person.  Viral infections disable these basic body functions to help provide a good reproduction space for the virus and other pathogens. 

Bacterial Infection

Mucus is one of the perfect places for bacteria to grow, which is why doctors stress the need to have your sinus drainage pattern return to normal as quickly as possible. 

 Since mucus is designed to collect as many pathogens and pollutants as possible before air enters the body, it is already chock full of bacteria,  If that bacteria is allowed to sit in the sinus for an extended period of time, it could lead to a bacterial sinus infection.  This is considered to be a general bacterial infection, and it actually is either caused by or may cause a regular sinus infection.  

This variety of sinus infection is contagious, but it is only in rare occasions.  Since the bacteria stays confined to the actual sinus, it is rare for another person to come into contact with it, but contact would spread the bacteria.  Since bacterial sinus infections are not very common, and it is even rarer that they will not spread to other people, odd are you're safe.

So contrary to popular belief, a sinus infection is not contagious.  Even though it does provide a lot of discomfort, pain, and a potential trip to the doctor, you will not spread it to anyone around you.  If you wind up getting a sinus infection, look for the cause, instead of the infection itself, to be contagious.