Well Done Mum


How does my child's body Fight infection?

When germs infect your child's body, their immune system makes antibodies. Antibodies have two jobs. The first is to attach and destroy the germs. Because it takes time for your body to make enough antibodies, the germs may damage your child's body before the antibodies can destroy them.

Their second function is to stay in your child's body to protect them against future infections. If the same germs try to infect your child again the antibodies will destroy the germs before they have a chance to make your child sick. This way of dealing with germs is called 'immunity'. It is why most people get diseases like measles or chickenpox only once, even though they might be exposed to them many times.


The problem with getting natural immunity from germs is that your child has to get sick before they develop immunity. In fact, some germs could make your child very sick or even kill them before their body could produce enough antibodies to destroy the germs.

How do vaccines work?

Immunisation is a simple, safe and effective way of protecting your baby against certain diseases. Your child is given a vaccines to which their body responds by making antibodies, the same as if they had caught the disease but without getting sick. These antibodies then destroy the vaccine and stay in your child's body and protect them against the actual disease.

All vaccines used in Ireland are safe but like all medicines there may be some mild side effects. These can include a sore or swollen arm or leg or a slight fever. Serious side effects to vaccines are extremely rare.
It usually takes a few weeks for vaccines to work, so your child will not be protected immediately.

Your health care provider, nurse or GP will give your baby the immunisations. The injections are given with a small needle into the upper arm, thigh or buttock.

Premature babies start their immunisation programme at the same time as full-term babies.
Childhood immunisations are free.

Timetable for Immunisation >