For a lot of her early years, she spent time going in and out of the wards, up until she was four-years-old.

And there were times when, unbeknownst to her young mind, her life hung in the balance because of her undiagnosed common variable immunodeficiency.

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"I had pneumonia three times before I had even turned five," Zoe said.

"And there were a few times when my family would gather in my hospital room and at the time I didn't know why, but now I'm older I can put two and two together."

Zoe said she often could only be at home for two weeks before having to go back into hospital.

"I always had an infection, whether it be in my sinuses or lungs, but I couldn't go very long without getting sick and that really worried mum and dad," she said.

Little did her family know, Zoe was struggling with a primary immune deficiency disease characterised by low levels of protective antibodies and an increased risk of infections.

This meant any illness could send her back into hospital, and winter would be a grueling time of year.

And if it weren't for her parents, she could have struggled more through life and not been diagnosed when she was four-years-old.

"It was scary, but it was also great to have an answer," Zoe said.

"And I think it was good for my parents to know they weren't crazy for thinking something wasn't right and advocating for me.

"But being diagnosed meant that I could start treatment, which has really changed my life."

While she has accepted the fact there is no cure for CVID, Zoe is able to receive a weekly or monthly intravenous immunoglobulin infusion, an injection made out of plasma from blood donors.

"It's fantastic because now an infection can be tackled simply with a course of antibiotics and I don't think I've been in hospital for at least 10 years now," she said.

"I am forever thankful for all the blood donors who have given plasma because without them, I wouldn't be here today."

However, there are people who aren't as lucky as Zoe.

Some suffer from severe combined immunodeficiency, which is a diverse group of more than 400 potentially serious, chronic illnesses that can lead to frequent or severe infections, swellings and autoimmune problems.

The Australasian Society for Clinical Allergy and Immunology has launched its Immunodeficiency Strategy to improve the health and wellbeing of people living with this disease and minimise the burden on individuals, carers, health services and the community.

"Due to their rarity, delays in diagnosis of primary immunodeficiencies are common," strategy co-chair Melanie Wong said.

"For infants and very young children with severe PIDs, this leads to severe complications due to recurrent infections and early death, despite being curable if treated in the first few months of life.

"That is why we are specifically calling for newborn screening of SCID.

"While screening is routinely performed in New Zealand, the United States, and in some European countries, it is not yet routinely available in Australia.

"It is only being trialled in NSW at present."

Zoe said she and others in Victoria were doing what they could to ensure this screening could be conducted across the state.

"It's important to me because I still don't know if my four-month-old son Theo has it," she said.

"While I'm the only one in my family who has it, it is genetic and I want to make sure my son can be screened as soon as possible.

"I want to make sure Theo doesn't have the same life I had early on."

It is estimated 70-90 per cent of people are still undiagnosed worldwide.

Victorian data shows in adults, the average delay from symptom onset to diagnosis is 8 years and every year of diagnostic delay costs years in life expectancy.

"SCID is fatal in the first two years of life without definitive intervention," ASCIA president elect Theresa Cole said.

"Early diagnosis is vital to allow curative treatment such as urgent haematopoietic stem cell transplantation, also known as bone marrow transplant.

"Screening is also likely to be more cost-effective for the health system than the cost of prolonged hospital and intensive care unit admissions. It should be a health priority in Australia."