It takes 7 days from the introduction of a pathogen for a specific immune response to begin. The specific immune response engages the use of T and B cells. T-cells are activated in response to a viral pathogen and B-cells are made in response to an introduced bacteria. The cells are very good at their job, however, 7 days is plenty of time for a pathogen to make itself at home, multiply and invade, which could defeat the B and T cells if the introduced pathogen's numbers are not controlled. Our body attempts to suppress the numbers of the pathogen by presenting a counter attack on day 3.
At this time, Complement Protein Activation begins. Complement proteins are made everyday in the liver and circulate in the blood. The classical pathway of activation is as follows: C1 and C2 bond, splitting C2 into C2a and C2b. C2a floats away. 2b bonds with 4 causing 4 to split into 4a and 4b. 2b and 4a bond creating 3. 4a floats away. C3 bonds with 4b and splits into 3a and 3b. C3b then splits C5 into activated C5a and C5b. C5b then binds to C6, C7, C8 and C9 forming a Membrane Attack Complex (MAC) that has lytic capabilities, in which the complex figuratively punches holes in the membrane of the bacteria, resulting in cytolysis. Basically, these holes allow fluid to enter the cell and it explodes. Before the MAC complex is created there is another weapon that is released in the splitting process. C3a and C5a are the most potent vasodilators that have been found. Vasodilation is a major player in the process of inflammation and phagocytosis, which both help to fight invaders.
During class the issue of immunizations and specifically the flu vaccine was discussed briefly. At first I was thinking that if we decreased the use of the flu vaccine (limiting the vaccine to the elderly and children), that maybe the virus wouldn't be forced to change and modify itself. Dana explained that virus's continually evolve anyway and that limiting the vaccine probably wouldn't help. There is the other issue though of the flu vaccine being helpful anyway, since it is a 3 year process to develop it. What are the chances that it will even be the right strand? I am not against vaccines, I just believe in extreme caution in the administration of them. The conversation about vaccines, led me to the situation with antibiotics and how doctors are warning patients and their families to not abuse the medication due to bacteria learning how to modify itself so that it cannot be treated with the normal prescribed antibiotics. Call me crazy, but I have been worried about this for years. If our antibiotics are rendered useless, we are not left with much to defend ourselves against many, many infections.
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As I was reading your blog, it was perfect timing to what is going on in the world right now with the Swine Flu. People are worrying because of the rapid spreading of this flu but after reading your blog and knowing what we know now about how a flu virus can quickly change shape and become a different strand, I of course, would be more cautious about where I'm hanging out these days. But at the same time, how can we, as a country, completely and 100% prepare for something like this knowing that it could change and become a new strain. We were stockpiled for the avian bird flu but why stockpile for something that could be different tomorrow? I am all for preventitive measures but how can the medical community prepare for something that they don't reallllly know what it's going to be. It makes you really want to know how the flu virus can change strains and do it so efficiently, where we cannot even manufactur something like that in the lab. If only we could know how bacteria and such learn to become adaptable to our medicines/vaccinations...then we could develop our own defense against them that prevents them from being able to morph and change into a strain that could get around those defenses...I don't know...crazy!!
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