Gaps in government funding are creating pockets of under-immunisation in refugee and migrant communities around Australia.
Health experts have warned that under-immunisation in refugee and migrant communities could create epidemics of diseases thought to be eradicated in Australia.
University of New South Wales Professor of Infectious Disease Epidemiology, Raina MacIntyre, said outbreaks of vaccine-preventable disease across Australia had already been linked to these communities.
"We've seen large outbreaks of measles - the largest since 1998 - in the last couple of years in Sydney and western Sydney and these have been definitely linked to under-immunised migrant populations," she said.
Eastern Access Community Health, which runs clinics and refugee health programs on the east coast of Australia, said up to 70 per cent of its clients were not fully immunised.
Professor MacIntyre blamed gaps in government funding.
"There is no universal, national initiative to catch up under-immunised migrants and refugees," she said.
"Say a child comes to Australia as a refugee or migrant at the age of 12 and so they've missed out on scheduled immunisation points on our national immunisation schedule. There's no national mechanism to ensure they get catch-up vaccinations."
Complex funding arrangements for vaccines
Most states don't fund catch-up immunisations for Hepatitis B, Human Papilloma Virus or certain strands of meningococcal disease.
Melbourne-based refugee community nurse Merilyn Spratling said her clients were keen to be vaccinated, but the cost was too high for some.
"Everybody wants to be vaccinated. There isn't anybody that says 'no I can't'. The only problem would be if they're moving away but then we liaise with the clinic they're going to so they don't fall through the gap," she said.
"The refugees and asylum seekers want to be vaccinated."
Tincan Khheing has two daughters but only one is eligible to get the HPV vaccine for free.
Ms Khheing said she can't afford to pay for the other.
"Eldest one is 19 years old. She's too old to get it from the government. The youngest one is 13 years old and she can get from the government but the 19-year-old can't because she's too old. I love my children and I don't want them to get the disease for cervical cancer. I want to protect them from sickness," she said.
Immunisations are funded nationally, but administered according to state criteria.
It's a complex arrangement for both patients and doctors.
The federal Department of Health and the Immigration Minister's office each referred SBS to the other, when asked to clarify funding arrangements for catch-up vaccines for refugees and migrants.
CEO of Eastern Access Community Health Peter Ruzyla said the funding arrangements were brutal.
"I call it the 'immunisations lottery'. Which of my children in my family and there's families with seven or eight children, which of those are in the immunisation age-range, the free immunisation age-range and which ones happen to fall outside of it?"
Diseases such as measles are largely eradicated in Australia.
Risk of disease outbreaks 'very real'
But Professor of Infectious Disease Epidemiology, Raina MacIntyre said it's still being imported from overseas.
"People of a migrant or refugee background who are going to their country of origin to visit their friends or relatives are more at risk because they are less likely to seek travel advice and more likely to be under immunised," she said.
Professor MacIntyre said that unless a person is under the age of seven, there is no national register of general immunisations.
She said this means that as people change locations and doctors their vaccination records are often lost, and the process of catching up on immunisations for those who want them, must begin again.