The parents have the support of the anti-vaccination group the Australian Vaccination Network.
The baby's father, who is seeking an injunction against the court order, was adamant the family would stay on the run indefinitely.
One of the doctors who alerted state authorities to the couple's refusal to have the baby vaccinated, Professor David Isaacs from Sydney's Westmead Children's Hospital, said that the child's rights were being ignored.
"If you do not immunise a baby in this situation, you're putting that baby's life at risk," he said.
He said if a baby gets hepatitis B at birth he or she will become a chronic carrier of the virus.
"About a third of those chronic carriers will die young from cancer of the liver or cirrhosis of the liver ... this is a horrible disease," he said.
New South Wales Assistant Police Commissioner Frank Mennilli declined to say whether the parents would be charged once they were found.
"It'll be something that'll have to be assessed once that child is located," he said.
Source-Medindia
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