Flu Influenza

Every time you turn around, it seems like the flu is making big headlines. From newspapers to talk shows to blog sites, the flu doesn’t want to go away! Why do we care so much about the flu? Should we be more worried about it? These are good questions that are tough to answer, but one thing’s for certain: the flu can affect you and your loved ones without warning—and it can have serious repercussions.

Our Immune System and The Flu

Although we are a relatively new species, we have overcome many physical and biological obstacles to become the versatile beings we are today. Humans have the amazing ability to adapt and to control our environment. One could argue that most of our adaptation occurred via human ingenuity, such as inventing cars for transportation, but adaptation via immunity is much more complex and profound.

On a biological scale, our bodies are constantly fending against infection. Billions of microorganisms are constantly attacking our cells at any moment, yet our level of health is more or less stable, thanks to our immune system.

Types of Influenza

Over the years, humans have battled against fierce microscopic contenders, particularly influenza viruses. Human influenza viruses are members of the orthomyxovirus family, and they are classified as influenza A, B, and C. Influenza A and B are the ones that commonly affect human populations. Influenza C occurs less frequently and has less severe symptoms. There are many variants of influenza, which are characterized by the letters H and N.

The full name of a particular influenza strain is characterized by the:

  • virus type

  • host species (not included if human in origin)

  • geographical site

  • serial number of the virus

  • year of isolation

  • H and N variants.

For example, the current “swine flu” is known as A/California/07/2009 (H1N1) in scientific circles.

Flu is a communicable disease, meaning that it can spread from one infected person to another. Influenza viruses are usually transmitted via respiratory air droplets, which are expelled during a cough or sneeze. The virus particles can gain entry via the surface of the respiratory tract, airways, and lungs.

Influenza - Influenza Virus

The Influenza Problem and the Swine Flu

The influenza virus is notorious for its ability to cause repeat epidemics and global pandemics. But why does influenza keep coming back?

First of all, influenza has the ability to infect across species, such as from birds to humans. Secondly, once the virus is in humans, it continues to alter its makeup to evade immunity so that it can “hide” from attack.

Scientists have learned much about the how the influenza virus works. However, these viruses remain unpredictable and dangerous. We don’t know when or where the next influenza outbreak will occur.

The H1N1 influenza virus, or “swine flu,” is currently a worldwide threat, and news about the swine flu is everywhere. That’s why it’s important to learn more about swine flu symptoms, flu shots, and what you can do to prevent its spread. You should also stay updated on news about the swine flu to keep yourself and your family healthy.


Behrens, G. and Stoll, M. Pathogenesis and immunology. In: Influenza Report. Kamps, B., Flying Publisher, Wuppertal, 2006.

WebMD staff. (2009). Types of flu. Retrieved November 27, 2009, from the WebMD Web site: http://www.webmd.com/cold-and-flu/flu-guide/advanced-reading-types-of-flu-viruses?page=2.

World Health Organization staff. (2003). Influenza fact sheet. Retrieved November 27, 2009, from the WHO Web site: http://www.who.int/mediacentre/factsheets/2003/fs211/en/.