The Importance of Immunisation

Category: Newborns

Every parent wants the best for their baby. For nine whole months, your baby was kept safe in your womb but the minute he takes his first breath and lets out his first cry, he is exposed to all kinds of illnesses and diseases. That’s where immunisation comes into play.


The decision to vaccinate can be a confusing one for some families, as we all want to do what is right for our children. Some parents base their decision on statistics from books and on the internet. Some people base their decision on personal experience.
Whatever your decision regarding vaccinations, the goal is always the same, to raise happy and healthy children who are able to blossom and reach their potential in life.

What is Immunisation?
Immunisation is a simple, safe and effective way of protecting children against harmful infections before they come into contact with them in the community. Immunisation uses the body’s natural defence mechanism – the immune response – to build resistance to specific infections, explains Dr Arunachalam Sridhar, registrar, Dept of Neonatal and Developmental Medicine, Singapore General Hospital. It helps children stay healthy by preventing serious infections. The diseases which can be prevented by routine childhood immunisation are included in the National Childhood Immunisation Schedule.

Immunisation and vaccination – is there a difference? Well, according to Dr Sridhar, there is. “Most people use the terms ‘vaccination’ and ‘immunisation’ interchangeably but their meanings are not exactly the same,” he clarifies. Vaccination means having a vaccine – that is actually getting the injection. Immunisation means both receiving a vaccine and becoming immune to a disease, as a result of being vaccinated.

Getting that Jab
While many of you may know just how important vaccinations are, have you ever paused to wonder just exactly how it works? All forms of immunisation work in the same way. They can be active or passive, explains Dr Sridhar. When a person is vaccinated, their body produces an immune response in the same way their body would after exposure to a disease, but without the person suffering symptoms of the disease. When a person comes in contact with that disease in the future, their immune system will respond fast enough to prevent the person developing the disease. This is active immunisation. Passive immunisation involves administration of the antibodies from outside (which are produced by the body in active immunisation) to initiate the protection quickly without delay. But the duration of protection is short as the antibodies get broken down naturally by the body, says Dr Sridhar.

Not only can your child be immunised by a paediatrician but your family doctor, general practitioners in your polyclinic or public or private hospitals with such facilities, can provide the service as well.

Knowing Your Vaccines
Vaccines contain either: a very small dose of a live, but weakened form of a virus; a very small dose of killed bacteria or virus or small parts of bacteria; or a small dose of a modified toxin produced by bacteria. Vaccines may also contain either a small amount of preservatives or a small amount of an antibiotic to preserve the vaccine. Some vaccines may also contain a small amount of an aluminium salt which helps produce a better immune response, explains Dr Sridhar.
They’re important but are they safe? Vaccines are generally safe. Like other medications, explains Dr Wendy Sinnathamby, specialist in paediatrics and consultant from Raffles Children’s Centre, vaccines can occasionally cause reactions.
Most side effects last a short time and the child recovers without any problems. Common side-effects of immunisation are redness, soreness and swelling at the site of an injection, mild fever and being irritable or unsettled. Allergy to vaccinations is very rare. If your child has a serious egg allergy, she should not receive influenza or yellow fever vaccine as these contain traces of egg. Measles vaccination is safe in a child with egg allergy. If you notice that your child has rashes, eye swelling or breathing problems after receiving a vaccine, you should bring your child immediately to your doctor for further assessment and management, advises Dr Mas Suhaila Bte Isa, consultant, Division of Paediatric Infectious Diseases, National University Hospital.

Being Protected
While it may take at least two weeks to generate an immune response to a vaccination, it is certainly worth the wait. Dr Sinnathamby explains that some vaccinations provide lifelong immunity or protection against a disease while others offer shorter term protection and multiple booster doses are required.
Children should be immunised to prevent them from getting serious infectious diseases that can kill or cause long-term disabilities or health problems.
Immunisation is the safest and most effective way of giving protection against a disease. After immunisation, your child is far less likely to catch the disease if there are cases in the community. The benefit of protection against the disease far outweighs the very small risks of immunisation, explains Dr Suhaila. If enough people in the community are immunised, the infection can no longer spread from person to person and the disease dies out altogether. This is how smallpox was eliminated from the world and polio has disappeared from many countries.  
Keep in mind that if enough people in a community are vaccinated, it would be harder for a disease to be transmitted between people who are not vaccinated, so that disease will be less prevalent in that community, thus offering protection to the few who may not be vaccinated. This is called herd immunity, explains Dr Sinnathamby.
But with all the vaccines that your child is lined up for, from the moment he is born, can immunisation overload the immune system? No, says Dr Suhaila. Children come into contact with many antigens (substances that stimulate an immune response) each time, and the immune system would respond in specific ways to protect the body. Without a vaccine, a child can only become immune to a disease by being exposed to infection, with the risk of severe illness whereas if illness occurs after vaccination, it is usually insignificant.

Not Right Now
There are very few medical reasons to delay immunisation. If a child is sick with a high temperature (over 38ºC) then immunisation could be postponed until the child is recovering. A child who has a runny nose, but is not ill can be immunised, as can a child who is on antibiotics and obviously recovering from an illness, says Dr Suhaila.
However, should you delay your child’s jab for any reason, be sure to get him back on track with his vaccinations as soon as possible. Reports have shown that a large number of these deaths are in children under one year of age from vaccine-preventable diseases including whooping cough, polio and measles. Hence, immunisation is recommended early in life to protect our children from these dangerous diseases, explains Dr Suhaila.

What about Natural Immunity?
Natural immunity and vaccine-induced immunity are both natural responses of the body’s immune system. The body’s immune response in both circumstances is the same. In some cases, explains Dr Suhaila, vaccine-induced immunity may diminish with time; natural immunity, acquired by catching the disease is usually life-long. The problem is that the wild or natural disease has a high risk of serious illness and occasionally death. Children or adults can be re-immunised (required with some vaccines but not all) if their immunity falls to a low level. It is important to remember that vaccines are many times safer than the diseases they prevent. 

Thanks for sharing!