VACCINES, VACCINATION AND IMMUNIZATION, AND DISEASES CONTROL
Introduction to Biology, SCI 120
Vaccines, Vaccination and immunization, and disease control
Vaccines are defined as chemicals prepared from antigens (disease causing agents) that are injected into the human body, in order to activate the body’s defense mechanism against harmful diseases. Vaccines are made mostly for diseases that are fatal or incurable. Vaccination is defined as the process of injecting vaccines into the body in order to initiate disease protection. Immunization is the process of developing resistance against harmful diseases, most commonly through the use of vaccines. Vaccination is carried out to prevent from numerous diseases including hepatitis, measles, polio, and influenza. Here is a brief history of how vaccines were developed.
In the late 1700s, when England was battling the effects of cowpox, a country doctor named Edward Jenner made note of the similarities between a disease known as ‘grease’ and the cowpox. It was after he was told by a milkmaid that she could not catch smallpox because she had had cowpox that Jenner made an enlightening discovery. In 1976, he carried out a very audacious experiment. He injected a young boy with the cowpox virus, and after letting the boy heal from cowpox, he injected the boy with smallpox pus. Just as Jenner had predicted, the boy did not catch smallpox.
The act of synthesizing vaccines evolved over centuries, and now, they are successfully eradicating many health diseases. Here is a brief summary of how the vaccines work on the human body, and protect us against harmful diseases. Whenever the human body is under attack by germs like bacteria or viruses, the germs multiply, developing into an infection. The infection in turn is what develops into a disease. The immune system, which comprises of white blood cells in the blood, fights off the infection. The white blood cells comprise of B lymphocytes, T lymphocytes and macrophages. Macrophages are white blood cells that fight and swallow the harmful germs, leaving behind a part of the antigen. The anti-bodies that are produced by the B-lymphocytes attack the antigens left behind by the macrophages. The T-lymphocytes are the white blood cells that attack and kill the body cells that have been already been infected. The body after the infection attack retains a few T-lymphocytes, commonly referred to as memory cells as a defense. If the same virus attacks again, the body’s immune system is activated more quickly than the first attack and the defense mechanism is also stronger.
Vaccines are manufactured by taking the antigens of the disease for which the vaccine is being created and making them weaker, so that they do not infect the body. This creates memory cells that protect the body from future attacks. Many people believe that the naturally acquired immunity is better than the immunity acquired by vaccines. The effects of naturally acquired immunity could however be unpredictable, which may also prove fatal. It is for the same reason that vaccines were developed in the first place. There are a few side effects that appear as a result of vaccinations.
The most common side effects include pain, swelling or redness at the injection sites, mild fever, shivering, fatigue, headaches, and muscle and joint pains. There is also a very rare side effect to vaccinations, the probability of which is almost one in a million. That is an allergic reaction to the vaccine. This result could prove life threatening, however, if treated properly, and on a timely basis, could be reversed.
So the question now is, why use vaccines? There are many reasons to justify that question. Ever since the vaccine was first used, it has been successful in eliminating a lot of diseases that could prove fatal and life threatening. The diseases that we were once powerless against, as the influenza and all forms of pox have been successfully eradicated. Also, it is a lot easier to have oneself vaccinated, than to bear the costs of treating the disease. Many diseases that could cripple a person like polio can also be avoided. Getting oneself vaccinated can prevent a person from infecting not only himself, but also the people around him. This is because; a person who has been vaccinated cannot pass on the infection to those around him.
Many people find it easier to get their children vaccinated rather than subsequently making them suffer through the pain of catching the disease. Even though, vaccines show no visible benefits after use, they work on the inside, making the body’s defense mechanism stronger. So that if the virus attacks, the body is well equipped to protect itself from disease. A single vaccines mostly counters one disease, however, different vaccines have been produced that are designed to combat multiple infections. The last decade has seen immeasurable success in developing and improving vaccines. There are however many limitations even to the use of vaccines. Even though, they protect us from the diseases that have so far been encountered by man, they still cannot prepare us against diseases that are not discovered by man up till today. Also, like every other micro-organism, infections also undergo genetic mutations which could change their structure, and give the infection new properties that the body may not be able to keep at bay. But the man can only attempt to protect himself to the best of his abilities. For this purpose, vaccines are the best option that is available to us. However, with the development in viruses and bacteria, man is also trying to keep up with vaccine research and production.
References
Bonnie A. Maybury, O. a. (n.d.). Vaccines--How and why. Retrieved from Access excellence: http://www.accessexcellence.org/AE/AEC/CC/vaccines_how_why.php
CDC. (2013, February). Understanding how vaccines work. Retrieved from http://www.cdc.gov/vaccines/hcp/patient-ed/conversations/downloads/vacsafe-understand-color-office.pdf
choices, N. (2014, April 4). Vaccine Side effects. Retrieved from http://www.nhs.uk/conditions/vaccinations/pages/reporting-side-effects.aspx
