Flu Immune 500

Every year, millions of adults and children suffer with influenza, the flu. This disease quickly spreads through our communities every winter, despite, our efforts to prevent germs from entering our bodies and our homes. Most people know the symptoms and the proper treatments but not what causes the flu.

To understand what causes the flu, you must first know, what is a virus and an infection. A virus is a non-living organism (parasite) that can only survive by living inside of another living thing, like humans. Once in the human body, it turns healthy cells into virus producing cells as the virus multiples. An infection is the virus spreading throughout its host interfering with the host’s normal functions. The flu is caused by flu viruses that multiple once in the human body causing an infection. These viruses exist in our air making it easy for them to enter our bodies. There are three types of flu viruses; Type A, B and C. All of the flu viruses attack the upper respiratory tract, the organs involved with breathing such as the nose, larynx, trachea, bronchi, and lungs.

Type C is a milder strain of the flu. Symptoms are usually very mild and can be similar to a cold. Being infected with the Type B flu virus can develop into a minor illness. In some older adults, serious complications can develop. Type A is the most common strain found in humans.

Type A is the most dangerous of the three types. It has been responsible for the most flu epidemics. What makes this strain so dangerous for humans, is its ability to constantly change its protein structures. The Type A flu changes using two processes, antigenic drift and antigenic shift.

It is possible to develop the flu several times during the cold and flu season. Type A and B can both change its structure through the “antigenic drift” process. This process allows small changes to occur over time in the strain. When small changes occur, the antibodies produced to fight the infection cannot recognize these changes. As a result, re-infection can happen again and the flu symptoms reoccur.

The Type A flu virus can also change through the antigenic shift process. Major changes happen to the strain causing subtypes or new strains to come into existence. A flu shot made to fight a specific strain of the flu, will not be able to recognize these new strains. This is the reason why you can still get the flu after receiving a flu shot. In addition, the body’s natural defenses have to produce new antibodies for each new strain or subtype. This may not happen immediately if you have a weaken immune system. In the meantime, the flu virus is causing serious medical complications and re-infection by a new strain can happen at any time.

Unfortunately, there is no cure for the flu. Flu viruses exist in our environment and we cannot prevent them from entering our bodies. Developing an accurate flu vaccine is difficult since the flu viruses are constantly changing their protein structure. Getting a flu shot may protect you from one specific flu strain but not newer ones. The only defense against the flu is our own immune system. Keeping your immune system healthy, will allow it to produce the necessary antibodies to fight the flu over and over again.