#594 Why do we lose our voice when we are sick?

Why do we lose our voice when we are sick? We lose our voice because our vocal cords become inflamed.

Let’s look at how the voice works to start with. We all have vocal cords inside our larynx, more commonly known as a voice box. The larynx is at the top of the trachea, the pipe we breathe through, and just in front of the esophagus, which is the tube we swallow food and drink down. There is a flap called the epiglottis which closes off the trachea when we eat or drink so that we don’t choke to death, but it isn’t always effective. When we swallow, the muscles around the larynx move it up so that the epiglottis can close off the trachea, and this is why we can feel it move when we swallow.

The larynx is made up of the area above the vocal cords (the supraglottis), the area with the vocal cords (the glottis), and the area below the vocal cords (the subglottis). The top part is connected to the throat and the bottom part is connected to the trachea. The larynx is made of cartilage to give it support and it has muscles that move it. Halfway down the larynx, we have the vocal cords. They are on the edges of a band of fibrous tissue called the vestibular folds. When we want to speak, we breathe out air from our lungs and it goes up the trachea and into the larynx. We can use our muscles to open and close the vocal cords, narrowing or widening the gap between them. The air makes the vocal cords vibrate and their position changes the pitch at which they vibrate, changing our voices and allowing us to speak. Men usually have a larger larynx than women, which is why their voices are usually deeper.

So, why do we lose our voices when we are sick? It happens because of inflammation of the larynx. When we get a viral infection, such as a cold or the flu, the virus enters our body through our eyes, nose, or mouth. They are usually coughed out by an infected person and they hang in the air long enough to be breathed in, or an infected person will have them on their hands and maybe put them on a surface that someone else will touch. That person will then touch their face and the virus will be in the body. Once inside the body, the virus attaches to the lining of the nose or throat and settles down to start replicating itself.

It takes about two days for the body to realize there are aliens inside it. This is called the incubation period and happened because in the early stages of the infection there are not many viruses and the chance of the white blood cells running across one is slim. As the viruses start to replicate and build up, it starts to move to other areas and gets itself ready to do its work and be transmitted. At this point, there is enough of the virus for it to be detected by the body and the immune system is fired into action.

One of the ways that the immune system fights a viral infection is through inflammation. The inflammation is caused by inflammatory cells that command local blood vessels to release fluid and plasma into the surrounding tissue. This fluid causes the tissue to swell and traps the viruses where they are. The white blood cells can then go in and kill them. When the viruses are in your throat, they will get down into the larynx and the inflammatory cells make the larynx and the vocal cords swell. Any change in their size will change the pitch of your voice, resulting in that “cold” voice we all know. If the swelling increases, it could reach the point where the vocal cords cannot vibrate at all and this results in a lost voice. It will get better once your body gets rid of the viruses and the inflation goes down.

You can also lose your voice if you overuse it. If you shout a lot, your vocal cords can become inflamed. When you shout, you have to expel more air and your vocal cords vibrate much more and much faster than they usually do. This can cause them to become inflamed and then they cannot vibrate, in the same way as when you have a viral infection. It usually goes away with rest. And this is what I learned today.

Photo by Gustavo Fring: https://www.pexels.com/photo/man-taking-medication-for-throat-6285300/

Sources

https://www.macmillan.org.uk/cancer-information-and-support/laryngeal-larynx-cancer/the-larynx

https://www.ncbi.nlm.nih.gov/books/NBK534630/

https://en.wikipedia.org/wiki/Inflammation

https://my.clevelandclinic.org/health/symptoms/21660-inflammation

https://askabiologist.asu.edu/questions/how-viruses-work