Childhood vaccination is one of the most effective ways to prevent serious illnesses and deaths in children, yet there are reports of parents delaying vaccinations or are deciding not to vaccinate their children altogether.
It is understandable that some parents are wary of vaccinations and share concerns about the possible side effects and allergic reactions. This hesitancy is likely to stem from a lack of understanding about how different types of vaccines work.
“Some parents are overwhelmed by the number of vaccines and are concerned that their baby is too young or weak to receive multiple vaccines at the same time, as well as be able to cope with the side effects. This is a misconception and scientific data show that it is safe for babies to receive several vaccines together,” says Dr Shermela Appan, a consultant paediatrician at StarMed Specialist Centre.
As advancements in medical science have brought about more vaccines against serious diseases, parents need to be well informed about the types of vaccinations available so they can make the right choices for their children to stay well and safe.
Understanding how vaccines work
It starts with understanding how vaccines work. A vaccine is a type of biological substance that is designed to train the body’s immune system to fight off harmful viruses or bacteria.
It contains a tiny amount of the killed or greatly weakened part of the bacteria or virus that the person is being vaccinated against.
Dr Appan explains that upon receiving a vaccine, the body’s immune system will attack the harmless form of the virus or bacteria from the vaccine and will produce antibodies to destroy it. This exposure to the agent is then stored in the memory of the immune system.
When the child is exposed to the same virus or bacteria years later, the immune system can recognise it, and is prepared to fight it to prevent infection.
Babies are exposed to thousands of germs in the environment once they leave the protected environment of the womb. A baby’s immune system is immature and exposure to infectious diseases could pose a serious threat to the baby’s health.
Deciphering the types of vaccines
Vaccines can be classified as inactivated or live attenuated (weakened).
Inactivated vaccines are made from a protein or part of the virus or bacteria, whereas a live attenuated vaccine uses the weakened form of the virus, explains Dr Appan.
A live attenuated vaccine does not cause disease in healthy people but is able to stimulate a protective immune response. Examples of live attenuated vaccines include those for rotavirus, chickenpox and measles, mumps and rubella (MMR).
Some vaccines like those for hepatitis B and measles are able to provide long lasting immunity upon completing the course. However, others like tetanus and influenza require booster shots for continued protection.
Compulsory vaccinations by law in Singapore
Children in Singapore are vaccinated according to the National Childhood Immunisation Schedule that lists the recommended types of vaccines from birth till 17 years old.
Among them, two are required by the law – one to protect against diphtheria and the other measles. Both diseases are highly contagious and can be fatal.
Diphtheria is a bacterial infection which causes a fever and sore throat. A thick membrane forms rapidly that covers the tonsils and the nasal passage, leading to difficulty in breathing and swallowing. The toxin can also cause heart and kidney failure.
Measles, especially in the young, can cause severe lung and brain infection, which often results in permanent brain damage or death.
These vaccines are given as combinations with other vaccines. Diphtheria is given with the tetanus, pertussis, polio and haemophilus influenzae type B vaccine, while measles is given with the ones for mumps and rubella.
“Combination vaccines reduce the number of clinic visits, saving parents’ time and also help lessen the child’s distress as the number of shots is reduced” says Dr Appan.
Although not compulsory, the rotavirus and hepatitis A vaccines are also recommended, as these diseases have harmful effects on the young.
Rotavirus is a common infection of the digestive tract in children under five. It is found in human faeces and spreads easily through contact with dirty surfaces. It causes severe vomiting and diarrhoea especially in infants, often requiring hospitalisation.
The Rotavirus vaccine is given orally in two or three doses, depending on the vaccine brand. The first dose should be given before the child turns 15 weeks old.
Hepatitis A virus can cause severe liver disease. As with most viral infections, no specific treatment is available, and the best recourse is prevention through vaccination, says Dr Appan.
Suitability for vaccination
While it is suitable for most infants and children to receive vaccines, there are occasions when a child may not be suitable for them.
Vaccination should be postponed if a child is suffering from moderate or severe acute illness. Once the child recovers, you can proceed with the vaccine in one to two weeks.
Vaccination is not suitable for children who have exhibited a serious allergic reaction to a previous dose of a vaccine, in children with poor immune system, or in those who have active cancer or are on medication that weakens the immune system.
It is best to seek medical advice if you are unclear.
Side effects of vaccinations
Taking vaccines may come with side effects, but these are often manageable.
Common side effects include fever, irritability, sleepiness, fatigue, pain or redness at the injection site, and loss of appetite.
These symptoms can be managed at home, for instance, by giving paracetamol syrup to bring down the fever and giving smaller but frequent feeds if they have poor appetite. Placing a cool wet towel on the injection site can also help soothe the baby.
Some may develop a small lump at the injection site or a mild rash, but these will subside after a few days.
However, if rashes appear rapidly in the first half hour after vaccination, and the child also experiences swelling of eyes and lips, seek immediate medical attention as it could possibly be anaphylaxis, a severe allergy, which is a medical emergency.
Mild vomiting and diarrhoea are common side effects after the rotavirus vaccine, but they usually subside after a few days.
However, if the child is crying excessively and vomiting within a week after the vaccine, seek medical consultation immediately.
Full subsidies for vaccinations under the National Childhood Immunisation Schedule (NCIS) and childhood developmental screening are available for Singaporean children at StarMed Specialist Centre.
All recommended vaccines under NCIS and optional vaccines are available at StarMed and can be paid with funds in the Child Development Account.
About Dr Shermela Appan
Dr Shermela Appan has been a Singapore Ministry of Health accredited paediatrician for the past 41 years, with special interests in children’s growth and puberty, asthma and allergies.
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