ALMOST 80,000 Australian children are not immunised against deadly diseases, and the highest number live in Sydney's west.

Experts say the "baby Einstein" demographic - parents who take an intensive interest in their children's education and health, eat organic food and use alternative medicines - is responsible.

Sydney's west has an immunisation rate of 90 per cent for five-year-olds but last financial year was home to 3600 children who were not fully immunised. In wealthy Manly, Mosman and eastern Sydney, however, fewer than 85 per cent of children are immunised in some age groups.The figures are contained in a National Health Performance Authority report.

The World Health Organisation says immunisation rates for measles must be above 93 per cent to prevent its spread. Immunisation expert Julie Leask says parents who perform extensive research and are often suspicious of medicine are more likely to object to vaccination.

"I think what these figures say is ... you can't rely on herd immunity in your region," the University of Sydney academic said.

Australian Medical Association president Dr Steve Hambleton said the removal of an $18.50 government incentive for doctors to chase up unvaccinated children would exacerbate the problem.

New data on immunisation rates in smaller areas shows the Richmond Valley on the north coast, home to the anti-immunisation Australian Vaccination Network, has the lowest immunisation rate in the country. Only 82 per cent of one-year-olds are fully immunised, falling to just 80 per cent for two-year-olds and 75 per cent of five-year-olds.

NSW Health infectious diseases expert Dr Jeremy McAnulty said two children died on the north coast last year during a whooping cough epidemic that infected 24,000 people. Western and southwestern Sydney were also hard hit by a measles outbreak, with 199 cases last year.Naturopath and mother-of-two Genevieve Milton is convinced vaccines can be harmful and decided against immunising her sons.

Husband Darrell, however, is pro-vaccination and admits he is not entirely comfortable with the decision. "I don't know I totally agree with her but if Gen wasn't going into this armed with all the information that she obviously has, then I would be more against her," he said.Mrs Milton believes she can best protect sons Cadel, 4, and Keanu, 21 months, by strengthening their immune system with good nutrition, vitamins and good hygiene.

She says her boys "line up every day for their echinacea and fish oil" and stresses white sugar and flour must be eliminated from children's diets for a strong immune system to develop.

Originally published as 'Einstein parents' say no to needles