Definition of immunisation/vaccination –
“Immunisation is the process whereby a person is made immune or resistant to an infectious disease, typically by the administration of a vaccine. Vaccines stimulate the body’s own immune system to protect the person against subsequent infection or disease.” (WHO – 2018)
Explains Primary immune response –
The primary immune response occurs when person come into contact with a particular pathogen for the first time. It then takes a few days to fight the infection, because first the antigen has to be identified then the appropriate T cells, B memory and plasma cells and antibodies to form, usually takes longer than 4-7 days. The infected person recovers completely, if sufficient antibodies are made to destroy the antigens and memory lymphocytes are produced. During this time, the person displays symptoms of the disease. It usually takes 7 to 10 days for the level of antibody to peak. The primary immune response mainly occurs in the lymph nodes and spleen.
Immune response to vaccine –
Primary immune response is the initial immune response to vaccines. When the antigen is injected into the human, this stimulates the production of antibodies and T and B memory cell, specific to the certain antigen being administered protecting the individual for a long period of time.
Explains Secondary immune response –
The secondary immune response occurs when the person is exposed to the same antigen for the second time (3rd, 4th, etc). The B memory cells and T memory cells within the body activate quickly usually within 1-4 days. The pathogen is destroyed quickly, often before any symptoms of a disease become evident. It usually takes 3 to 5 days for the level of antibody to peak. This response mainly occurs bone marrow, followed by the spleen and lymph nodes.
Immune response to vaccine –
Secondary immune response is after the individual is vaccinated and then exposed to the disease. The memory B and T cells created from the primary immune response react faster and quicker compared to the primary immune response. This is because the cells know how to kill off the invading pathogens. Therefore, the individual is unaffected by the disease because the vaccination has made them immune.
Vaccinations prevent infection:
When the vaccine is injected into a person, the immune system produces antibodies and memory B and T lymphocytes that destroy that specific pathogen. Memory cells are activated when an individual comes into contact with the same antigen, producing antibodies to destroy the pathogen quickly, protecting the individual from the debilitating and sometimes life-threatening consequences of infectious disease.
Herd immunity –
‘is a form of immunity that occurs when the vaccination of a significant portion of a population (or herd) provides a measure of protection for individuals who have not developed immunity’ (vaccination today, 2018)
Identifies forms of vaccines –
There are 4 main types of vaccines:
Live, attenuated vaccines – weakened form of the germ which causes the disease. E.g. yellow fever, measles, mumps, chickenpox, smallpox, rubella.
Inactivated/killed vaccines – killed version of the germ which causes a disease. E.g. flu, rabies, polio, hepatitis A.
Subunit, recombinant, polysaccharide, and conjugate vaccines – use of specific pieces of the germ protein, sugar, or capsid (casing around the germ). E.g. human papillomavirus (HPV), Hepatitis B, shingles, whooping cough.
Toxoid (inactivated toxin) vaccines – a toxin made by the germ which causes a disease. Creates immunity to the parts of the germ that cause a disease. E.g. tetanus, diphtheria.
Brief History prior to vaccinations –
Vaccination come from the latin word “vacca” meaning “cow”. In the 18th century, Edward Jenner physician and scientist, observed that milkmaids always caught ‘cowpox’, a mild disease, from the cows but never suffered the deadly smallpox. Jenner used pus frim a cowpox sore to deliberately infect people with cowpox. This caused later immunity to smallpox.
Outlines success stories using Smallpox, diphtheria and polio as examples –
SMALLPOX:
Smallpox is a viral disease that enters through the throat and lungs. Symptoms of the disease includes headaches, obvious vesicles on the skin, fever and backaches. Smallpox first appeared in 10000 BC around areas of Asia and Africa. The cause of spread was by explorers and traders. This disease was responsible for 1 in 10 of all deaths in Europe in the 19th Century, (WHO, 2018). The first smallpox vaccination was performed by Edward Jenner by inoculating people with cowpox. This method expanded globally by the WHO in 1967. The WHO consistently immunised people with the vaccine. By 1980, the WHO announced the world free of smallpox. This is now commonly known as the most outstanding success against any disease in history.
DIPHTHERIA:
Diphtheria is a disease caused by a highly contagious bacterium that is spread through the air into respiratory surfaces, or by close physical contact. Diphtheria can lead to permanent nerve and heart problems, even after patients are cured. Therefore, prevention through vaccination is far better than curing the disease. 100 years ago, from all those infected with diphtheria 50% would die. After WWII large epidemics occurred in Europe. In 1923, a vaccination was released for diphtheria. This then spread globally in 1974, and by 1990 the worldwide immunity rate was 80%. This disease is still occurring in present day developing countries.
POLIOMYELITIS “POLIO”:
Polio is viral disease which attacks the motor neurones of the brain and spinal cord. Symptoms include muscle spasms, back pains, paralysis and high fever. In Ancient Egypt, during the 19th century, the polio disease killed hundreds and thousands of people. The mortality rate began to fall by the 20th Century. However, during this time it killed or crippled hundreds of Australian children every year. By 1955 the polio vaccination was first introduced (injected but now taken orally) and in 1988 the WHO began the Expanded Program on Immunisation (EPI) campaign the number of cases dropped by 80% in 1990. It is nearly eliminated from Australia and most of the world. However, it continues to affect people in areas of Africa.
Evaluation of effectiveness of Vaccination programs –
Through the use of vaccinations programs made globally by the World Health Organisations (WHO) many death causing diseases, have been eradicated on a global scale. For example, since the start of WHO’s worldwide vaccination program for smallpox. It has been completely eradicated from the planet. The use of vaccination programs has reduced the spread of diphtheria from cyclic academic through the WHO, 1974 Expanded Program on Immunisation (EPI).
Although it not has been completely eradicated vaccination programs have reduced the morbidity and mortality of diphtheria dramatically, although it is still a significant child health problem in countries with poor EPI coverage. Also, cases of polio have decreased by 99% due to the EPI vaccination programs. Polio now survives only amongst the world's poorest and most marginalized areas, especially taking advantage of the vulnerable children. It is evident that vaccination programs are very effective to eradicate diseases around the world.
The World Health Organisation (WHO) current vaccination program “World Immunisation Week 2018 – #VaccinesWork” (24th-30th April) aims to “highlight the importance of immunization, and the remaining gaps in global coverage, underscore the value of vaccines to target donor countries and the importance of investing in immunization efforts and highlight the ways in which everyone – from donors to individuals – can and must drive vaccine progress” (WHO, 2018). From last year’s program 116.5 million infants worldwide have received 3 doses of diphtheria-tetanus-pertussis vaccine, ultimately protecting them from infectious diseases which can cause serious illness and disability (WHO, 2018).
Outline of present day issues –
People are not getting vaccinated
In today’s society, it is said that between six and eight million children still die each year from diseases that could have been prevented by early immunisation. This is due to barriers such as a lack of transport, poverty, limited clinic opening times, isolated areas, social exclusion and lack of knowledge. (mostly in developing countries).
However, it is also the hesitant and refusal, which prevents parents from immunising their children. A small portion (2%) of Australians do not vaccinate their children due to the common myths that surround vaccination such as; vaccinations cause sudden infant death syndrome, asthma, allergies, autism and that they contain mercury. This stigma needs to be overcome because vaccinations are safe.
Assessment of consequences to society of lack of vaccination –
Vaccinations save millions of lives annually. According to the World Health Organisation (WHO), more than 2-3 million deaths are prevented due to immunisation. Many parents against vaccinating their children fear that the vaccine will cause side-effects, and are frightened side effects such as asthma, allergies and autism. However, this is untrue, as there are very limited finding proving that this is true.
The choice to not vaccinate children, will not only mean that the kid will have a low immune response, but they will be a threat to the public. The lack of vaccination means that the parts of society who have low immune systems such as babies aged 6-12 months and the elderly are more a risk to catching diseases. This will therefore bring back vaccine-preventable diseases. This also means that mortality and morbidity rate will increase. The more parents that choose to not vaccinate their children, the greater the risk that infection will spread in the community.
Even when travelling, if an individual chooses not to vaccinate, they may fall at risk to catch a vaccine-preventable disease. This means that once someone is exposed to an infectious disease which could be prevented, and they bring it back home. This disease can spread to those with weakened immune systems.
Final summary/conclusions –
It is evident that vaccination does save millions of lives. If children or even adults are not vaccinated it is put not only themselves but also the wider community at risk of life threatening diseases which could be treated by vaccinations. From the examples used such as, smallpox, polio and diphtheria, disease which have been completely eradicated or nearly eradicated due to vaccination, it is clear that to be immunised means to live a healthy and better life.