Immune deficiencies in children explained

By Associate Professor Alberto Pinzon Charry

Paediatric allergist and immunologist in Woolloongabba, Brisbane

Most children get sick from time to time. Colds, ear infections and viruses are a normal part of growing up, especially in the early years.

But occasionally, some children seem to get infections more often than expected, take longer to recover, or become unusually unwell from relatively common illnesses. This can sometimes lead families to wonder whether there may be an underlying problem with the immune system.

One possible explanation is an immune deficiency.

What does the immune system do?

The immune system is the body’s defence system. It helps recognise and fight infections caused by viruses, bacteria and other germs.

In children with an immune deficiency, part of this system may not work properly. This can make it harder for the body to respond to infections effectively.

Some immune deficiencies are present from birth, while others develop later in life.

What signs might suggest an immune deficiency?

It’s important to remember that frequent illness alone does not necessarily mean a child has an immune deficiency.

Children in childcare or school can experience many viral infections each year, particularly when they are young.

However, certain patterns may raise concern, including:

• unusually frequent infections
• severe or difficult-to-treat infections
• repeated pneumonia, sinus infections or ear infections
• poor growth or weight gain
• infections that keep returning despite treatment
• a strong family history of immune disorders.

Sometimes the clue is not just how often a child gets sick, but how serious the infections become or how long recovery takes.

Immune deficiencies can look different in every child

Some children experience mainly respiratory infections, while others may have skin infections, gastrointestinal symptoms or ongoing fatigue.

In some cases, symptoms can be subtle and develop gradually over time.

This is one reason why diagnosis can sometimes take time, particularly when symptoms overlap with common childhood illnesses.

How are immune deficiencies diagnosed?

Assessment usually starts with a detailed medical history and physical examination.

A specialist may ask questions about:

• the type of infections your child gets
• how often they occur
• whether antibiotics are needed frequently
• growth and development
• family history.

Blood tests are often used to assess how different parts of the immune system are functioning.

What happens if an immune deficiency is diagnosed?

The management of immune deficiencies depends on the type and severity of the condition.

Some children require only monitoring and occasional treatment, while others may need more specialised care to help prevent infections and support their immune system.

The reassuring news is that many immune deficiencies can be managed very effectively once identified.

Why early recognition matters

When children experience ongoing illness, families can sometimes feel exhausted and frustrated trying to work out what’s happening.

Identifying an underlying immune problem early can help:

• reduce repeated infections
• improve quality of life
• support growth and development
• provide families with clearer treatment pathways.

Importantly, many children referred for assessment do not end up having a serious immune deficiency, but investigating persistent concerns can still provide reassurance and answers.

A balanced perspective for parents

It’s easy to become worried when your child seems to be unwell more often than other children around them.

In reality, most frequent childhood illnesses are part of normal immune development. However, if infections seem unusually severe, persistent or repetitive, it’s reasonable to seek further advice.

Parents know their child best, and persistent patterns are worth discussing with a healthcare professional.