Why is Vaccination so Important?

Vaccination saves lives!

The human immune system is fundamental to maintaining health as it is trained to resist and fight off disease causing bacteria and viruses. At every moment there are swathes of hostile bacteria, fungi and viruses which swarm on our body. Yet we are able to remain relatively healthy – most of the time. Our immune system is uniquely able to provide immunity against pathology-causing organisms, or pathogens. Certain pathogens are so virulent, however, that our immune system cannot provide immunity quick enough before the disease causes long term impairments or death. This is where vaccinations become so overwhelmingly critical, not only to individual health but to the health of entire populations.

A macrophage hard at work keeping the body safe from foreign substances.In brevity let us firstly consider the composition and basic physiology of the immune system: The Innate Immune System:

Composed of two separate divisions which complement each other the immune system is able to provide a complete defense structure. The innate division of the immune system is sometimes referred to as the non-specific immune system since it does discriminate on what foreign substances it protects against. Elements of the innate immune system essentially protect against all foreign substances, pathogenic organisms included. There are two divisions of the innate immune system – the first line of defence is the skin and mucosae (internal linings of mouth, nose, gastrointestinal tract etc). Secondly, there are a number of immune cells which circulate the body through the blood and lymph. The main immune cell which we shall focus on is the macrophage. Macrophages move throughout the body and essentially engulf foreign substances such as bacteria in a process called phagocytosis. Macrophages will only protect against foreign substances such as bacteria if they by chance happen to encounter them on their travels. They cannot actively seek out foreign substances in order to attack them – at least not without the help from other immune system elements.

A macrophage (red) engulfs a tuberculosis myobacterium (yellow)

If a bacteria penetrates the first line of defence and moves into the body encountered by cells of the innate immune system such as the macrophage, the bacteria is able to take hold of the host by reproducing constantly. As this happens the infected host begins to show symptoms of the disease that that bacteria causes. There are certain virulent bacteria and viruses that cause diseases that our immune system cannot respond effectively enough and in enough time to prevent long term damage or death. In such circumstances, our immune system may be helped by other components of the immune system now to be discussed.

Viruses and bacteria are the main disease causing organisms.The Adaptive immune System:

The second major division of the immune system – the adaptive immune system plays a significant role in long term immunity. This is where vaccination plays an important part. The adaptive immune system is quite complex and involves a wide variety of components, however, this article will attempt to address the concept simply. The adaptive immune system, as its name suggests, is able to adapt in response to certain foreign organisms such as bacteria and viruses that it has previously encountered. It is also called the specific immune system since many of the components of this system discriminate in terms of what they attack.

Antibodies have attached to a pathogen and have neutralised it. Now macrophages or T lymphocytes may come and kill the pathogen.

Humoral Division:

The adaptive immune system is further divided into subsections. The Humoral division of the adaptive immune system is concerned with the production of antibodies. Antibodies are Y shaped proteins which circulate through the body’s humor or fluids (Blood and lymph) and neutralize foreign substances. Every antibody has a unique target which is present on the invading organism or pathogen. This target is known as the antigen (Anti-body Generating). The interaction between an antibody and antigen can best be described like a lock and key. When the key inserts into the lock the antibody activates and the pathogen is neutralised. Antibodies do not eliminate the pathogen but neutralising them makes them available to other components which effectively kills and destroy the invading pathogen.

Antibody production:

Antibodies are produced within a special cell called the B lymphocyte or simply the B cell. On the first exposure to a certain foreign organism the B cell is said to be inactive. It does not begin to produce antibodies until it has encountered the foreign organism for the first time in a process called ‘differentiation’. Once the B cell is activated it produces many of these specific antibodies which seek out the specific foreign substance and neutralise it. When activated, some B cells become ‘memory B cells’ which are long living cells which become important on re-exposure to that specific organism at a later time.

Antibodies have attached to a pathogen and have neutralised it. Now macrophages or T lymphocytes may come and kill the pathogen.

On the second and subsequent exposures the memory B cell, already differentiated, instantly begins to produce antibodies and therefore your immune system is able to effectively defend against the foreign organism. In this scenario there is no delay period where the differentiation process has to occur and therefore with the much higher numbers of antibodies circulating the blood, coupled with the greatly reduced time the organism has to reproduce an take hold, our immune system will either completely prevent the disease progressing to show symptoms or will minimise the severity and length of time of the symptoms.

The problem with aggressive bacteria and viruses is that they may cause irreparable damage or death before our immune system can establish an effective defence against it. This is where the importance of vaccination is emphasised – by artificially installing a memory into out immune system of how to combat a specific organism, on exposure to the organism our immune system can act before the disease progresses.

B cells produce antibodies which circulate through the blood and neutralise pathogens.Vaccination is essentially a way of manipulating the immune system to create protection against a disease-causing pathogen without causing the disease within the person. There are a number of ways a vaccination may be created:

Killed or Inactive Viruses: This method is used primarily for viruses and involves treating the virus with heat or chemicals to ensure it is no longer infectious. These vaccines cause a significant antibody response and therefore create immunity through differentiating B cells so that memory B cells are available to ramp up antibody production on subsequent re-exposure to the pathogen.

Attenuated Pathogens: This method involves taking a disease causing organism and growing it in cells of other species so that the organism adapts to that species and therefore grows poorly in human cells. When the vaccine is introduced into humans our immune system will effectively remember how it defeated the pathogen on re-exposure.

Toxoids: Some pathogens cause disease by releasing toxins into the body. This method induces immunity by vaccinating specifically against the toxin. It therefore prevents disease when a pathogen releases toxin in the body.

Antibodies have attached to a pathogen and have neutralised it. Now macrophages or T lymphocytes may come and kill the pathogen.

The processes of creating these vaccines by using various chemical compounds is the argument that anti-vaxers mostly use to whip up hysteria over the dangers of vaccination. They’ll attempt to argue that neomycin and polymyxinB cause kidney damage and that streptomycin prevents protein synthesis and causes hearing loss. This is all true, however the age old saying ‘it’s the dosage that makes the poison’ continues to hold true. If anti-vaxers were in anyway educated on the processes of the human body then they would understand the flaws of their argument.

The DPT Vaccine:

Let us take the process of creating the diphtheria vaccine (usually administered as DPT for Diphtheria, Pertussis and Tetanus) for example: The process involves inactivating the Corynebacterium diphtheria pathogen using formaldehyde. Formaldehyde may be a toxic chemical, however the term toxic is misleading and overtly ambiguous. At high doses formaldehyde is toxic, however, the amount found in the DPT vaccine is so small it simply isn’t an issue. During normal body processes alone your body is generating and breaking down more formaldehyde than what is found in the DPT vaccine. In greater concentration many foods, including meat and fruit contain either formaldehyde or compounds which convert to formaldehyde in your body. An average adult contains about 2.5 micrograms of formaldehyde per millilitre of blood– that’s more than 10 times the amount more formaldehyde than the DPT vaccine contains.

Mercury is toxic in large doses. The insignificant amount which was once found in vaccines was not enough to be toxic.Neurotoxicity of Vaccines:

Furthermore, anti-vaxers will attempt to argue that neurotoxins, including aluminium and mercury (as thiomersal) cause various neurological conditions. The amount of aluminium found in vaccines is so insignificant compared to the amounts we ingest in our foods and drink. Our body has no problem metabolises these and therefore no problem metabolising the minuscule amounts found in vaccines. Thiomersal and thus mercury has been removed from vaccines since the early 2000s due to the scare campaign associated with the word ‘mercury’, however, a Japanese study found that autism incidence continued to rise with even greater pace after thiomersal was removed.

There is no reasonably argument that explains how these chemicals may cause problems when our body is at every moment generating and metabolising these compounds apart of the natural processes that passively occur without us even thinking of it.

This graph shows the period of time where Thiomersal was used in vaccines as the MMR interval. Incidence of Autism increased significantly after thiomersal was no longer added.

Herd Immunity:

This concept is incredibly important when we consider the overall health of the population, in attempts to control epidemics, pandemics and in achieving eradication of infectious diseases. It essentially describes a form of immunity whereby large proportions (a herd) of a population are immunised against a particular pathogen. It provides a larger chance of immunity for those who have not been vaccinated and where herd immunity is established and maintained, the spread of a disease is disrupted when a large part of the population are immune or less susceptible to the disease. Herd immunity holds that with a greater percentage of the population vaccinated the probability that someone who isn’t vaccinated will encounter another person who isn’t vaccinated is significantly decreased. Under these circumstances a link in the chain of disease transmission is broken and a disease can be contained. The herd immunity threshold percentage at which a disease’s begins to be contained is generally quite high. For disease such as Diphtheria, Polio, and Rubella the vaccination percentage required is around 80 – 85% of the population. For more virulent diseases such as Measles and Pertussis the herd immunity threshold percentage is in excess of 90 – 95%.

The importance and efficacy of vaccination is well established within the vast majority of society and overwhelming advocated by the health profession. A vocal minority group of anti-vaxers who wish to believe the mistruths about the safety and importance of vaccinations places the entire population at an increased risk of disease. The science is compelling – the truths are there – the evidence is out – vaccinations have saved more lives than any other form of medicine and will continue to save lives into the future. Everyone must be vaccinated – so let’s make it compulsory!

A serious threat to humanity – the rise of Antibiotic Resistance and the ‘superbug’

The evolution of bacteria is outpacing our ability to research new antibioticsThe single greatest threat to the world’s health care over the coming decade is the rise of the ‘super-bug’:

These are resistant bacteria which are able to withstand antimicrobial medicines including antibiotics, antifungals, antivirals and antimalarials

“Some bacteria are now so resistant that they are virtually untreatable with any of the currently available drugs. If we do not take action to address this threat, humankind will be on the brink of a post antibiotic era, where untreatable and fatal infections become increasingly common” – Simon Prasad and Phillippa Smith, Australian Office of the Chief Scientist.

The Antibiotic era begins: Most people would be at least remotely aware of Alexander Flemming’s discovery of penicillin in 1928 as an antibacterial agent. Although the antimicrobial effects of mold had been known for some time, Flemming’s discovery eventually led to penicillin’s mass production as an antibiotic medicine by the 1940s.

As the name suggests, antibiotics work to kill or destroy bacteria which invades our body. If bacteria infect our body and begin to reproduce, their cumulative effects on our body manifest as symptoms, making us ‘sick’. Although our immune system works overtime to fight off the infection it actually adds to many of the symptoms such as inflammation and makes us feel even sicker. Antibiotics are necessary to kill bacteria and help an immune system in overdrive. Different antibiotic drugs act on certain bacteria in different ways. Certain drugs may inhibit bacteria from converting glucose to energy or may prevent bacteria from building its cell walls. When antibiotics are at work the bacteria will die instead of reproducing. The problem with antibiotic resistant bacteria is that when our body is infected there is no means by which we can rid ourselves of the infection and their reproduction continues uninterrupted to a fatal point.

The over prescription and use of antibiotics has promoted the evolution of resistant bacteria

How do bacteria become resistant to antibiotics?

Bacterial evolution, which has always occurred, is the means by which bacteria may develop resistance to antibiotic drugs. While this is not new, nor is it surprising since all organisms evolve over time, the concern is the pace at which evolutionary changes are occurring. Bacteria may become resistant by receiving genes from already resistant bacteria or may achieve resistance through spontaneous mutations of DNA sequences during reproduction. If this mutation provides a favorable outcome for survival then it is passed on through reproduction to its offspring. The genetic changes that may occur include bacteria forming the ability to:

  • produce chemicals that destroy antibiotics
  • to build protein machinery to pump antibiotics out of the cell
  • make the cell impenetrable by antibiotics
  • modify its appearance so that it is unrecognisable to antibiotics

Staphylococcus Aureus, commonly known as Golden Staph is constantly giving rise to newer forms of the disease which are antibiotic resistant

The misuse of antibiotics prevalent in today’s society is largely responsible for the rising resistance:

Many practitioners prescribe antibiotics for viral infections such as the common cold which provides no physiological benefit except promote the evolution of bacteria. Viruses are non-living particles of genetic material and cannot be killed by antibiotics. Immunizations are essential to protect against many viruses including influenza. With up to date immunizations our immune system can generally fight off viral infections.

Quite alarmingly, a study conducted in 2003 found that 99% of antibiotic prescriptions at a specific hospital’s emergency room where not necessary. While this on some level may be excused due to the nature and necessity for quick medicine in emergency rooms, the over prescription of antibiotics by general practitioners is creating an environment where bacterial evolution is resulting in antibiotic resistance.

The alarming decrease in research for new antibiotics is a critical issue in the rise of antibiotic resistance:

The lucrative nature of drugs other than antibiotics has caused a shift in commitments to other research areas. Some cancer drugs can be sold at as much as $20,000 a course while antibiotics are sold at no more than $20 a course. The commercialisation of healthcare has a seen a dramatic shift in commitments where many companies have completely abandoned their research into antibiotics.

Many antimicrobial products including hand sanitizers, bathroom and household cleaners, soaps, mouthwash, toothpaste and garbage bags also contribute significantly to the rise of an antibacterial resistant era. Most of these bacteria that these products kill are generally good bacteria essentially to building stronger immune systems and maintaining good intestinal function. The tag that these products carry as being antimicrobial is nothing more than an expert advertising ploy to alarm mothers of the health of their children. These products are no more effective at preventing infection within the home than good personal and household hygiene with ordinary soap, warm water and plain detergents.

According to the Director-General of the World Health Organization, Dr Margaret Chan, “a post-antibiotic era means, in effect, an end to modern medicine as we know it. Things as common as strep throat or a child’s scratched knee could once again kill.”