5 Things You Didn't Know About The Flu

Think that after the many years you have lived on this Earth and after the numerous colds you've had, you would know more about the flu? Think again. Here are 5 relatively unknown facts about the flu!

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1. The influenza virus is not the one that makes you feel sick.

In fact, it is your own body that makes you feel sick. All the influenza virus, or the cold virus, does is enter the epithelial cells of your respiratory tract and kills them. Detecting this, your immune system sends billions of white blood cells there to kill both the viruses and infected cells. The white blood cells do this by both causing an inflammation and increasing the amount of mucus to trap the viruses. Also, the body raises its own temperature in order to kill the viruses, causing a fever.

2. Mucus does not cause a blocked nose.

The nasal lining is actually made up of erectile tissue (similar to that of the human male's penis), that is filled with blood vessels. Thus, the inflammation caused by the white blood cells results in the swelling of the blood vessels and hence swollen erectile tissue. This is a much larger cause of your blocked nose than increased mucus as it directly obstructs your airway while mucus which is largely liquid, can easily be removed.

3. You can catch a cold through your eyes.

Interestingly, your nasal cavity is connected to your eyes through a duct. What this means is that if a person sneezes and covers it with his hands, the virus is transferred onto his hands. Thus, if you shake hands with him, it is very likely that you will be infected too. This is due to the fact that we touch our eyes and noses much more often than we know, allowing the virus to reach the nasal cavity.

4. Women get more colds than men.

This may be because women are in contact with children more often than men. Children, with weaker immune systems, are less able to fight off the influenza virus and thus get colds more often. As a result, women also come into contact with the virus more often, increasing their chances of infection. Of course, there may be some underlying genetic reason. For example, women may have inherently weaker immune systems than men as women can get preganant and so the weaker immune system is to prevent their bodies from killing the child.

5. Yellow and green mucus is caused by white blood cells.

As previously mentioned, billions of white blood cells are sent to kill the viruses. To do so, the white blood cells release an enzyme that contains a heme group, or an iron ion, similar to what causes the red pigment of red blood cells. However, because the iron ion is in a different oxidation state and also surrounded by different molecules, it appears yellow in low concentrations and green in higher concentrations. This does not necessarily mean, though, that colored phlegm indicates a more severe infection and thus require more antibiotics, according to a study at the Cardiff University.

Thanks for reading!

Reference:

C. C. Butler, M. J. Kelly, K. Hood, T. Schaberg, H. Melbye, M. Serra-Prat, F. Blasi, P. Little, T. Verheij, S. Molstad, M. Godycki-Cwirko, P. Edwards, J. Almirall, A. Torres, U.-M. Rautakorpi, J. Nuttall, H. Goossens, S. Coenen. Antibiotic prescribing for discoloured sputum in acute cough/LRTI. European Respiratory Journal, 2011; DOI: 10.1183/09031936.00133910

NHS (2012, October 18). Five facts about colds. nhs.uk. Retrieved, May 23, 2014: http://www.nhs.uk/Livewell/coldsandflu/Pages/Fivefactsaboutcolds.aspx