Immunization is an important preventive measure to protect an individual from diseases.
The most common method of increasing immunization is through vaccination as it is the easiest, safest and most effective way to prevent diseases, especially among children who need additional protection from contracting illnesses.
Sunway Medical Centre, Sunway City’s Consultant Paediatrician and Neonatologist, Dr. Lee Mei Ling said, vaccinating children is very important because it protects and reduces the risk of them contracting serious or fatal diseases.
“A vaccine is a dead, or weakened version, or part of the germ that causes the disease in question. When children are vaccinated, their immune system will form antibodies to protect them from contracting the disease.”
She explained that the antibodies formed in children’s bodies will help their bodies to recognise certain germs or bacteria so that it can fight the disease in the future.
“When children are given one dose or an additional dose, they will be protected for years. This proves that vaccination is the most effective, safe and wise way to produce an immune response in the body, without causing any illness,” she said.
There are 12 preventable diseases listed under the National Immunization Program (NIP) including diphtheria, haemophilus influenza type B, hepatitis B, human papillomavirus, Japanese encephalitis, measles, mumps, pertussis, poliomyelitis, rubella, tetanus and tuberculosis.
NIP was introduced in the early 1950s and was designed based on the World Health Organization (WHO) Expanded Programme on Immunization (EPI).
“Based on the NIP Immunization Schedule, vaccines are provided free of charge in all government clinics and hospitals throughout the country to enable children to receive injections as scheduled,” she said.
She added that apart from the Japanese encephalitis vaccine which is only compulsory in Sarawak, every child must receive the vaccine according to schedule unless it is due to any underlying illness or medical condition which requires further discussion with the doctor.
According to Dr. Lee, the immune response to antigens and immunization can be divided into two categories which are the primary response or secondary response.
“The primary immune response to an antigen takes between 10 to 14 days to allow the body to produce antibodies.
“For the secondary immune response against the same pathogen, the memory cells generated before will react faster to produce antibodies to prevent infection, which is to kill the pathogen before it causes an individual to get sick,” she explained.
Dr Lee added, not all vaccines confer lifelong immunity as it depends on the type of vaccine.
“For example, vaccines for measles and hepatitis B will give immunity for life while tetanus or influenza will last for many years but require regular shots (boosters) to ensure continued protection.
“Therefore, parents need to keep records of their children’s vaccinations to ensure they are given injections or boosters when necessary,” she explained.
Vaccines can cause side effects to the recipients such as common fever, discomfort and pain at the injection site, but usually these side effects are minimal.
“The risk of causing harm is low. If the child experiences a side effect or reaction to the vaccine that is detrimental to their health, then the additional dose will not be given,” she added.
However, she said, there may be failure of immunization due to breakdown of the delivery system to provide potent vaccines to the individuals in need and also failure of immune response due to inadequacies of the vaccines or other factors inherent in the child.
“In addition, a weak immune system or immunosuppression caused by several factors including stress, malnutrition, concurrent infections or an immature immune system may also cause vaccination failure,” she said.
There is also the issue of children missing out on the necessary vaccinations (Missed Opportunity Vaccinations). This is because the parents do not check their children’s vaccine status in addition to the lack of knowledge about contraindications of vaccination.
“If children are not vaccinated, they will be exposed to the risk of contracting diseases that could be preventable through vaccines,” she explained.
She added that vaccination has sparked some debate but there is no convincing evidence to show that it is detrimental to its recipients.
“There may be parents who question the effectiveness of vaccines, but they should understand that vaccines or immunizations are important to protect their children for the long term.
“The benefits are far more than the side effects that may occur. Parents are also advised to listen to the views or opinions of relevant medical experts before making any decisions,” she said.
Dr. Lee Mei Ling
Consultant Paediatrician and Neonatologist,
Sunway Medical Centre, Sunway City
