Immunisation - Frequently Asked Questions

For information about immunisation, please see the topics below, call us on 9518 3534, or email

Is immunisation compulsory?

Immunisation is not compulsory but is highly recommended for all children.

In Victoria, you are required to present your child's immunisation history when attending child care, kindergarten or school. If an outbreak occurs, the child care centre, kindergarten or school can identify children who have not been immunised.

Children who are not immunised may be required to stay home to prevent them catching and spreading the disease.

How does immunisation work?

All forms of immunisation work in the same way.

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.

How long do immunisations take to work?

The normal immune response takes about two weeks to work. This means protection from an infection will not occur immediately after immunisation.

Most immunisations need to be given several times to build long-lasting protection. For example, a child who has been given only one or two doses of the diphtheria-tetanus-pertussis vaccine (DTPa) is only partially protected against diphtheria, whooping cough (pertussis) and tetanus, and may become sick if exposed to these diseases. But some vaccines give protection after only one dose.

Why do children get so many immunisations?

A number of immunisations are required in the first few years of a child’s life to protect against the most serious infections of childhood. The immune system in young children does not work as well as the immune system in older children and adults, because it is still immature. Therefore more doses of vaccine are needed.

In the first months of life, a baby is protected from most infectious diseases by antibodies from his or her mother, which are transferred to the baby during pregnancy. When these antibodies wear off, the baby is at risk of serious infections and so the first immunisations are given before these antibodies have gone.

Another reason why children get many immunisations is that new vaccines against serious infections continue to be developed. The number of injections is reduced by the use of combination vaccines, where several vaccines are combined into one shot.

Why should children be immunised?

There are two reasons for immunising every child in Australia:

  1. Immunisation is the safest and most effective way of giving protection against 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.
  2. If enough people in the community are immunised, the infection can no longer be 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.

Should parents be immunised?

Parents and other people (including grandparents and carers) who come into contact with young children are commonly carriers of some childhood infections and should be vaccinated against these diseases. For example, several studies of infant pertussis (whooping cough) cases have indicated that family members, and parents in particular, were identified as the source of infection in more than 50% of cases.

For more information on immunisations against childhood diseases, visit your local doctor or immunisation provider.

Are there any reasons to delay immunisation?

There are very few medical reasons to delay immunisation. If a child is sick with a high temperature (over 38.5ºC) then immunisation should 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 recovering from an illness.

Can immunisation overload the immune system?

No. Children and adults come into contact with many antigens (substances that provoke a reaction from the immune system) each day, and the immune system responds to each antigen 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. If illness occurs after vaccination, it is usually insignificant.

Why is immunisation still necessary in this day and age?

Many diseases prevented by immunisation are spread directly from person to person, so good food, water and hygiene do not stop infection. Despite excellent hospital care, significant illness, disability and death can still be caused by diseases which can be prevented by immunisation.

How safe are vaccines?

All vaccines currently available in Australia must pass stringent safety testing before being approved for use by the Therapeutic Goods Administration. This testing is required by law and is usually done over many years during the vaccine’s development. In addition, the safety of vaccines is monitored once they are in use, by the Adverse Drug Reaction Advisory Committee and other organisations.

Before vaccines are made available for use they are rigorously tested in thousands of people in progressively larger clinical trials. These trials are strictly monitored for safety. The approval process can take up to 10 years. As a result of such detailed testing, a number of vaccines that failed in these early tests have never been released.

Where can I find information about travel vaccinations?

Some health problems associated with international travel are vaccine preventable. Travellers should consult a travel medical centre, or their local doctor, at least 6 to 12 weeks before departure for a check-up and to discuss required and recommended vaccinations for specific regions. See our section on Travelling Overseas.

Can more than one immunisation be given at the same time?

Yes. Vaccinations recommended for babies and children can safely be administered at a single visit as long as they are given in separate syringes and in different parts of the body.

The recommended Immunisation Schedule has a reduced number of injections given at each immunisation session through the use of new combination vaccines.

Do some children get a disease despite being immunised?

Yes, it is possible, since no vaccine is 100% effective. A small proportion of those who are immunised will remain susceptible to the disease. In the cases in which illness does occur in immunised children, the illness is usually much less severe than in those who were not immunised.

Do you have to start the schedule again if you miss any vaccine doses?

If you have fallen behind it is easy to catch up. There is no need to repeat the doses already received and there is no need to get extra doses.

The vaccine schedule can safely and effectively be continued as if there had been no delay. The usual intervals between the vaccine doses are maintained or can be reduced if needed.

The immune system does not forget. To get full protection, a child needs to have all the recommended vaccine doses, preferably on time.

Should children be immunised while their mother is pregnant?

There is no problem with giving routine immunisations to a child whose mother is pregnant. In fact, immunising the child will protect the mother from being exposed to diseases like rubella.

What do I do if I miss a session?

You may attend a later session in the same month, or your regular session next month. There is no need to notify the Council of the change.

My baby has a runny nose / cold. Should I still continue with the immunisation?

A baby with a minor cough or cold without a fever, or a baby receiving antibiotics in the recovery phase of an acute illness, can safely be immunised.

Immunisation should only be postponed if a child is very unwell or has a high fever over 38.5ºC.

My child has an allergy to egg. Should I get my baby immunised against measles, mumps and rubella?

If a baby has an egg allergy, even an anaphylactic egg allergy, they can still be immunised with the MMR vaccine.

At the Royal Children's Hospital, 400 children with a history of egg allergy were vaccinated with the MMR vaccine and only 4 had minor reactions and none required treatment.

Can I bath my child tonight after they have had the immunisation?

Yes, it is advisable to treat your baby as you normally would and it is quite safe to bath them.

I want my child to attend child care or kindergarten, what are the immunisation requirements?

Please read: No jab, no play

Is your child due to start school next year?

Please read: Obtaining Immunisation Records

I am a new resident to the City of Monash, how do I register my child for immunisation?

Please read: Obtaining Immunisation Records

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Last updated: 22 June 2021