Vaccines – Both Sides of the Story
Staff, NPR, and Seth Mnookin. “As The Facts Win Out, Vaccinations May, Too.” NPR. NPR, n.d. Web. Retrieved February 27, 2014, from:
Due to the fact that we are currently immersed in flu season, we thought it would be appropriate to provide some information on vaccines.
Humanity’s only upper hand against the silent but deadly virus has been achieved through the use of vaccines. Vaccines have eradicated viruses such as small pox and nearly destroyed polio, as well as haltered the infection of millions from the flu virus. In order to understand how a vaccine works, you must first understand what a virus is and how the immune system works. [1]
A virus is basically a bundle of DNA inside a protein sheath; whether they are alive or not has been debated by microbiologists for years, but no one fully agrees whether they are living microorganisms or just complex molecules. [2] Regardless, on a basic level, viruses replicate themselves by shooting their DNA or RNA through the cell membrane of a host cell, which tells the host cell to produce copies of the virus inside of it. The infected cell eventually bursts, releasing the new copies of the viruses, which then go and infect more of your cells. This chain of events continues to occur until your body’s immune system can figure out how to kill them.
The immune system is in charge of protecting you from foreign ‘bodies’ such as viruses and bacteria; it keeps you free of illness and it fights off infection. There are two forms of immunity – innate and adaptive immunity. Innate immunity is your body’s first line of defense; it simply consists of your skin to block out foreign bodies; innate immunity also consists of cells such as macrophages that detect the microbe and then destroy it on the spot. [3] Your body knows what is good from bad because all of your cells are made up of molecules that allow it to identify which ones are yours, while the common cold virus’s identification molecules (antigens) for example are different (there are millions of different common cold viruses, which is why you can get it more than once). Once your body detects, say, a virus, a macrophage eats it and that cell will digest its parts but keep the antigens. The macrophage will then truck those antigens to your immune system’s home bases, your lymph nodes, and then this is where your adaptive immunity starts to figure out a plan of attack.
Adaptive immunity is exactly what its name implies – your body adapts and figures out how to destroy a specific virus. These cells are known as leukocytes (white blood cells). White blood cells can be seen as two different cells of the adaptive immunity called B and T cells. B cells make antibodies, which is a molecule that fits around the antigen molecules of a virus; your body produces billions of different shapes of antibodies. Your body makes so many so that one that fits the antigen of a virus might run into the virus by chance; if this happens, the antibody will turn into a plasma cell and emit loads of that specific antibody so that it can fight that specific microbe. Antibodies latch onto the surface of a microbe and tell other cells like macrophages or T cells to come eat or destroy it. T cells customize themselves to find that specific virus and kill any cells that are producing this virus. They do so by learning exactly what they are looking for by using the antigen harvested from one of the perpetrators and brought back by a macrophage. Once a T cell knows its enemy, it can sniff out infected cells and stimulate interferon, a chemical they secrete into the cell to stop viruses from replicating. Helper T cells can also activate other cells like macrophages or other T cells to kill virus-infected cells by leaving a chemical trail that alerts cells in that area. Once a virus has been eradicated from the body, more cells that performed the task of destroying it are then transformed into memory cells, made to play the role of an assassin on a never ending hunt for that virus, in case you ever come in contact with it again. This is why you cannot get the same virus more than once and is the key to why a vaccine is so useful. [1] [2] [3]
Vaccines take advantage of your body’s skill of remembering a virus and how to destroy it. They vary from a weakened form of the virus, to a dead form of the virus, to just the virus’s antigens. The weakened form of the virus just sort of sits there and does nothing, but your immune system acts against it as if it were the full strength virus. The weakened form of the virus is very effective but there is the risk of it mutating and turning into an active form of the virus that can make you sick; also since they are “alive”, they must be refrigerated, making it harder for them to be shipped and stored in poor countries. [1]
A second form of vaccine is a “killed” virus vaccine, where the genetic material is destroyed by radiation so that the genetic material does not work, but the antigens are still there. The problem with this is that it does not make the immune system respond as adamantly as the live, inactive forms do and it requires booster shots. On the other hand, this form of vaccine does not need to be refrigerated, making them more accessible for poor countries because they can be freeze dried. [1]
A third form is called a subunit vaccine, which is just the virus’s antigens so the immune system just produces the customized T cells that destroy it. Unfortunately, this form of the vaccine contains just the essential antigen molecules of the virus so sometimes the wanted immune response is not as severe as is needed. They are also very hard to make because they require so much more research so that scientists can figure out which antigens create the best immune responses. [1]
Vaccines are very important to public health because they give us an upper hand against the virus by making our bodies think that we are infected, giving our bodies a head start. This way the T cells or antibodies that were triggered by the vaccine have time to turn into memory cells so that our bodies can respond immediately when we come in contact with the actual virus.
These are just the cold, hard facts about vaccines, but there is a more compelling side as we dig deeper in the history and purpose of vaccines; this side is enveloped in controversial debates.
Today, every child born is expected to be vaccinated with some 30 vaccines by the age of 18 months, and by the age of five have up to 38 shots. [4] These shots, while well documented and tested to produce no harm to children, are covered in controversy. Some ask, “Is it necessary to give infants so many shots?” and some fret over the potential of negative effects. Those who worry believe to see a correlation between the rise of autoimmune diseases in children and vaccine history. Are we actually hurting ourselves in an effort to protect us?
There are two large controversial topics in the discussion about vaccinations: their potential negative effects, as mentioned before, and the mandates for vaccines, particularly those that are required for public school attendance.
In 1955, two batches of polio vaccine contained live virus, which caused an outbreak of polio. In the 1970s, a paper was published linking pertussis vaccination to permanent brain damage. [5] Today, the argument is that the increasing rates of autism and learning disabilities are linked to mandatory immunizations, specifically the MMR (measles, mumps, and rubella) and DPT (diphtheria, tetanus, and pertussis) vaccine. Thimerosal is a mercury-based neurotoxin that “should not be in our sewers let alone our bodies.” [6] In the past, thimerosal was very common in vaccines; however, by 1999 it had been removed from most vaccines due to fears of its link to autism (although there was no scientific evidence.) It’s true that historical records show that incidences of autism did increase around the time when the MMR vaccine was introduced in the US, however there are two issues with using this as a claim: awareness of autism in general was still increasing at the same time, so we cannot claim that the MMR vaccine causes autism – there is only a correlation – and autism in the UK did not increase after MMR was introduced there. [5]
Speaking of MMR and DPT; because both treat common childhood diseases, when the effectiveness of them was discovered in the 20th century, the government rushed to make them required for public school attendance. Ethical debates and objections to these compulsory vaccinations have arisen, often because of religious or philosophical beliefs. In the case of the vaccine for the human papillomavirus (HPV), objections have ranged from “religious concerns that a vaccine to protect against an STD contradicts abstinence-based messages [to] …human rights questions about the fairness of providing a vaccine to one sex only.” Due to our rights, all 50 states allow vaccination exemptions for medical contraindications, 48 states allow religious exemptions, and 20 states allow exemptions for philosophical reasons. [7]
Despite the controversial debates over vaccines, they have proved to increase public health over time and are vital in keeping our society healthy and safe. But what do you think? Leave a comment below.
[1] “Understanding Vaccines.” NIAID Science Education. U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES, n.d. Web.
[2] “Virus.” Virus. The Encyclopedia of Earth, n.d. Web. 27 Feb. 2014. <http://www.eoearth.org/view/article/156858
[4] “| K.N.O.W. Vaccines | KNOW…The Vaccine Controversy |.” KNOW Vaccines RSS. N.p., n.d. Web. 04 Mar. 2014.
[5] “To Vaccinate Or Not to Vaccinate.” Disabled World. N.p., n.d. Web. 04 Mar. 2014.
[6] “Your DPT Shot Could Cause Autism.” DPT Vaccines and Their Link to Autism. N.p., n.d. Web. 04 Mar. 2014.
[7] “Ethical Issues and Vaccines.” History of Vaccines RSS. N.p., n.d. Web. 03 Mar. 2014.