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Antibiotic & Vaccines

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Bacteria and the Virus

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Antibiotics and Vaccines

vaccinesThe human body is an advanced combination of systems, being a part of the animal kingdom and among the most developed species in existence.  It is also a macro-organism, as opposed to a microorganism, and is therefore subject to invasion by a variety of microbes and viruses (considered part-living, part-inorganic).  Microorganisms include prokaryotes (like bacteria and archaea) and eukaryotes like the protozoa and limited chromista and fungi; viruses are a single or double strand of DNA or RNA surrounded by a protein membrane (resembling the organic) but because they cannot survive or reproduce without infecting a host cell, they are not considered living things.  Of greatest interest in medicine are bacteria and viruses because people come into contact with them far more than with protozoa, chromista, or fungi.  The body, of course, has its own microscopic defenses in place to combat the harmful effects of intruders in the form of its immune system – the combination of the body’s efforts to protect itself from the harmful effects of pathogens and other foreign substances, destroy diseased or weak cells, and remove even cellular-level debris using the body’s own advanced structure and special suite of organs, tissues, cells, and cell products to build its defenses, recognize threats, react, fight pathogens, repair damage, and improve the defense, preparing for similar future invasions.  However, this system is not always sufficient and needs some aid.  The best and longest standing immunity is that which is naturally acquired but throughout history, medicine has proven to be integral to the survival of mankind, and two prime components of medicine are antibiotics and vaccines.


The body’s immune system makes antibodies that are designed to counter specific types of antigens – molecular components of intruders that induce a specific type of immune system response, like the creation of antibodies to link to antigens in order to neutralize them.  Sometimes, due to some type of invasion for which the body is not prepared, either due to its own lack of maturation, some existing disorder, or simply the extraordinary harmful potency of the pathogen, the body needs emergency aid and therefore must import antibodies.  Antibiotics are anti-microbial drugs whose specific antibodies work to counter the effects of specific microorganisms that could prove harmful to the body, particularly bacteria (often called anti-bacterials).

Pathogen’s Resistance
Antibiotics can only fight disorders brought on by bacterial infection and not a viral one because their types of antibodies are suitable for the antigens of living organisms, not those of viruses.  What’s more is that if antibiotics are taken in response to viral infections or in other inappropriate ways, the pathogen becomes desensitized to harm and makes its effect on the human body even more pronounced (although, in rare cases, there is no drug that can fight the pathogen effectively and every kind of medicine and method of administration could be considered “inappropriate”.) 

Antibiotics Composition
What exactly are antibiotics?  What are they made of?  Are they themselves living things or something else?  Well, the body’s naturally-created antibodies are a component of living things just as antigens are components of bacteria and viruses, and antibiotics are typically no different.  They are not bacteria themselves nor are they protozoa because those are typically the type of pathogens they fight, but they can be fungi or other types of organisms or the products / refuse of those organisms that are imported into the body to fight certain species of bacteria and protozoa.  For example, penicillin, one of the most widely known and celebrated milestones in the field of medicine, is the secondary metabolite (metabolism refuse) of a type of mold called penicillium chrysogenum, of the fungi kingdom, and it is an excellent antibacterial that is effective against a variety of bacterial infections and as such, is still used today.  After the discovery of penicillin, advancements were made and new antibiotics were discovered that were effective against particular types of bacteria (and sometimes protozoa), crucial in the fight against world-plaguing diseases like syphilis and tuberculosis.  Most of the antibiotics that we use today are of the classes discovered before the mid-80s.  As for terminology, “anti-bacterial” products are used more for soaps, cleaners, disinfectants, etc. while “antibiotics” are used for medicine but at the cellular / molecular level, they both work the same way, killing or preventing growth of bacteria. 


Vaccines vs Antibiotics
As noted previously, the best defense a body has is that which it makes itself in response to pathogen or pathogen-like intrusion.  This actively acquired immunity can happen naturally with the body’s recovery from disease or with immunization administered in the form of a vaccine – a substance resembling a pathogen that contains the antigen in a weakened form so that the immune system can create the appropriate antibody with ease and with little risk of introducing harmful substances into the body, and so that the immune system’s memory T-cells (a type of white blood cells) can remember this type of antigen, recognize it the next time it invades the body, and stimulate B-cells (another type of white blood cells) to create antibodies that will neutralize the pathogens and killer T-cells that can simply destroy the invaders.  Antibiotics are reactive medicine and a form of passive immunity because they don’t induce the creation of the body’s own antibodies or of memory cells to recognize antigens in future invasions but instead enter the body (usually being swallowed in the form of pills) as readymade antibodies for the purpose of fighting specific bacterial infections; vaccines, on the other hand, are preventative (prophylactic) medicine and a form of active immunity because they get the body to learn to recognize and fight against particular types of pathogens, strengthening its defenses and making it less dependent upon medication in the future.  Unlike antibiotics, vaccines are not susceptible to futility due to a pathogen’s resistance to readymade antibodies because they get the body to develop its own antibodies in real time.  Vaccines are therefore not limited to fighting bacteria, because the body’s immune system is capable of recognizing and fighting all malevolent intruders, including viruses.


Vaccination – the administering of vaccines – is usually in the form of giving of a shot (needle carrying the weakened pathogen that is injected into the body) but there are many ways that these can be administered.  Microorganisms or products derived from them used in vaccines may represent a particular disease but by inducing the correct immune response, actually offer the development of resistance to one or multiple other diseases.  Vaccines can be of many different types: inactivated, attenuated, toxoid, subunit, conjugate, valence, heterotypic, and experimental.

Types of Vaccines

Inactivated refer to dead virulent microorganisms or viruses – powerful pathogens that typically interfere with the immune system and are therefore hard to fight without aid – that had been destroyed by the use of chemicals, heat, radiation, or even antibiotics; influenza (cold), cholera, bubonic plague, polio, hepatitis A, and rabies are among the types of diseases (dead, of course) used for these vaccines.  Attenuated vaccines are those of weakened but active viruses, including yellow fever, measles, rubella, mumps, typhoid, and particular strains of tuberculosis.  Toxoid vaccines are inactivated toxic compounds derived from microbes and include vaccines like tetanus, diphtheria, and crotalus atrox.  Subunit vaccinations include only the antigen component of the immune system-triggering pathogen; examples of these are Hepatitis B virus, human papillomavirus (HPV), and influenza.  Conjugate vaccinations are bacterial coats linked with immune system-triggering antigens; Haemophilus influenzae type B vaccine is a conjugate vaccination.  Valence vaccines are those that can be used to immunize the body against multiple strains of a disease or multiple diseases (more than one type of antigen).  Heterotypic vaccines are made from microorganisms or viruses that are pathogenic for other organisms but only mildly for the organism being treated, including the Bacillus Calmette–Guérin (BCG) vaccine made for protecting babies from tuberculosis.  Apart from these, there are experimental vaccines that feature the use of dendritic cells (from neurons) linked with antigens, linking of one microbe or virus with the DNA of another, T-cell receptor peptides, only the DNA of microorganisms, and synthetic elements resembling real microbes and viruses.


The human body’s immune system is a very advanced response system but sometimes it needs help.  Some viruses and bacteria are resistant or “sneaky” in nature so that they can slip past recognition and cause harm to the body.  When there are readymade antibodies and there is little time to provide any prophylactic immunization, antibodies that can respond to that particular type of bacterium (or other microbe) can be ingested (usually in the form of pills); these types of readymade antibodies are called antibiotics.  When there is time to administer prophylactic immunization, dead or weakened and alive microbes (or active / inactive viruses), their products or derivatives, other components or combinations of components can be administered (usually in the form of a shot) to trigger the immune response because of the antigen contained in the vaccine so that the body can create the appropriate antibodies and memory cells to counter the fake threat and be prepared for the real one when it invades.  Human history has proved the necessity of the science and art of medicine in every society, and antibiotics and vaccines are essential in the practice of medicine.


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