How do vaccines work? A step-by-step guide to immunisation

African Vaccination Week is recognised annually during the last week of April. The objective of the African Vaccination week is to create awareness about the importance of vaccinations in the combat of vaccine-preventable diseases and, in doing so, grow the immunisation programmes carried out in various African countries. There have been growing discussions and debate about the role and effectiveness of vaccinations ever since the COVID-19 breakout, and the subsequent countrywide roll-out of the state vaccination plan. Health insurance broker, Bloom, together with their partner Momentum Health4Me, bring you this helpful guide to understanding what a vaccine is and how it works.

What is a vaccine?

A vaccine is a medical product that provides acquired immunity against a particular infectious disease and, in doing so, aids in combating disease-causing pathogens in our bodies. It is a safe and effective method for preventing or controlling certain life-threatening diseases in both young children and adults. The vaccine usually contains elements of dead, weakened or lab-produced substances that stimulate the immune system.

What is immunity?

Immunity is the protection your body develops against further infection by a pathogen. The body’s immune system is our natural defence mechanism against infectious diseases. However, certain diseases, like the coronavirus, can overwhelm the immune system, which could result in a serious, life-threatening illness or permanent side-effects. Once you’ve had a certain infection, the body usually develops a resistance against the same toxin, which is known as ‘immunity.’

Are vaccines safe and how do vaccines work?

Yes. Research to date indicates that vaccines are safe. Vaccines, or immunisations, assist the immune system in its defence against pathogens. The way this works is that the vaccination allows the body to recognise the novel disease and subsequently stimulates the body to produce antibodies that will fight these antigens or pathogens. As your body responds to a vaccination, it develops an immune response. Vaccinations are administered either by injection or with oral drops and many vaccinations consist of two or even three separate parts. The first part is the antigen and the second is the adjuvant. These parts will assist your immune system in its response against an infection, which will help you develop the required immunity.

Why are vaccinations so important?

Vaccinations are important for children as it is the means by which to prevent infections, like polio or TB. Since the organised roll-out of immunisations by governments and organisations across the globe, millions of lives have been saved. This is because prevention is better than cure. Put simply, it is more effective to prevent disease than to treat the symptoms and its various complications.

What vaccinations do children need in South Africa?

Immunisations for South African children are offered free of charge at state clinics. While parents are not legally obligated to have their children vaccinated, it must be noted that many schools will not admit your child without the required immunisations. There are 11 vaccinations recommended for children, which form part of the country’s national immunisation programme. These include:

  1. Tuberculosis, which is a highly contagious disease that affects one’s lungs and is, according to the World Health Organisation, the leading cause of infectious deaths. The TB vaccination is the Bacillus Calmette Guerin (BCG) and is administered to children at birth.
  1. Poliomyelitis, is a virus that causes paralysis and is spread through contaminated water, food or infected people. The polio vaccine is called the Oral Polio Vaccine (OPV) and is administered in two parts, the first at birth and the second at six weeks old.
  1. Diphtheria, is a bacterial infection that affects the mucous membranes in the throat, making breathing difficult. The disease can also damage one’s kidneys, heart and nervous system. The Pentavalent Vaccine (5-in-1) is administered in three parts. The first is given at six weeks, the second at ten weeks and the third at 18 months.
  1. Pertussis (whooping cough), is a highly infectious respiratory tract infection to which infants pare particularly susceptible. The disease can also cause pneumonia, seizures and even permanent brain damage. The pertussis immunisation forms part of the Pentavalent Vaccine, which is administered in three parts.
  1. Tetanus is a disease caused by a bacterial toxin for which there is no cure. The disease attacks one’s nervous system leading to painful muscle contractions. The tetanus immunisation also forms part of the Pentavalent Vaccine, which is administered in three parts. In addition to this, there is a Tetanus and Reduced Risk of Diphtheria Vaccine administered in two parts. The first at six years of age and the second at 12 years of age.
  1. Haemophilus influenzae is a serious bacterial infection that causes pneumonia and meningitis. It is transmitted by infected people and almost exclusively affects children under the age of five years. The Haemophilus vaccine also forms part of the Pentavalent Vaccine, which is administered in three parts.
  1. Pneumococcus is a bacterial infection that causes ear and sinus infections. It is spread by infectious people. The Pneumococcus immunisation is the Pneumococcal Conjugate Vaccine (PCV) and it is administered in three parts. The first is given at six weeks, the second at 14 weeks and the third at nine months.
  1. Rotavirus is a serious infection that causes inflammation of the stomach and intestines resulting in severe diarrhoea, fever, stomach pain and dehydration. The Rotavirus vaccine (RV) is administered in two parts. The first is given at six weeks and the second at 14 weeks.
  1. Measles is a viral infection of the respiratory system, which caused more than 110,000 deaths in 2017 alone, most of whom were children under the age of five. The Measles vaccine is administered in two parts. The first is given at six months and the second at 12 months.
  1. Human papillomavirus is a viral, sexually transmitted disease that can cause cervical cancer. It is recommended that children get the vaccine at about 11 or 12 years of age before they become sexually active.

It’s important that vaccinations are administered to children at the correct time. Check the Department of Health’s Extended Programme of Vaccination schedule to make sure your child gets the right vaccination at the correct age.

What vaccinations does Momentum Health4Me cover?

The Health4Me Gold, Health4Me Silver and Health4Me Bronze health insurance plans all cover an annual influenza vaccination for each member on the plan. Normally, a flu injection would cost between R69.99 and R87. Flu circulation is seasonal with ‘flu season’ starting in the first week of June and lasting for about 12 weeks. Getting a flu vaccination early will help protect you from infection. Health4Me health insurance plans cover the cost of flu vaccines for members at several approved partner pharmacies, like Dis-Chem, Clicks, MediRite and Pick n Pay Pharmacies.

At Bloom, we’re committed to healthy living and good health, which is the reason we encourage our members to make smart lifestyle choices and decisions when it comes to combating infections, like flu or vaccine-preventable diseases. Likewise, make sure you’re covered by an affordable health insurance plan for your medical healthcare needs.

Get in touch with one of our expert broker consultants for your medical insurance quotes and sign-up for health insurance cover for yourself and your family.

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You understand and acknowledge that all users of the Bloom website are responsible for their own medical care, treatment, and oversight. All content provided on the website, is for informational purposes only and does not constitute medical advice. Neither is it intended to be a substitute for an independent professional medical opinion, judgement, diagnosis or treatment.

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