The towns of Katoomba and Leura have among the lowest vaccinations rates in NSW, new national date has revealed.
While western Sydney suburbs generally had high vaccination coverage, the Katoomba/Leura postcode was ranked sixth lowest in the state at 81.4 per cent.
The 2015-16 figures, released on June 8, reflect the number of five-year-old children who are fully vaccinated. In the 2780 postcode there were 22 five-year-olds not fully vaccinated.
Sydney's 2000 postcode had the worst childhood vaccination rate in the country at 70.5 per cent.
However, Australia's overall national childhood vaccination rates are on the rise.
Overall 92.9 per cent of children under five were fully immunised in 2015-2016, leaving roughly 7 per cent (22,128 children) who had not received all their scheduled vaccinations and short of the national 95 per cent target.
But there were marked disparities between local communities often separated by just a few streets.
"When looking at smaller areas, like postcode areas, we see much greater variation in immunisation rates, from a high of almost 100 per cent and a low of 71 per cent for fully immunised five-year-olds," Australian Institute of Health and Welfare spokesperson Michael Frost said.
The data suggests more than one in four children in these postcodes were not fully vaccinated. It's worth noting the population of five-year-old children is small in many suburbs. A dozen children who are not fully vaccinated can drag down the rate by about four percentage points.
The Turnbull government's landmark "no jab no pay" policy targeting vaccine refusers came into force on January 1 and removed the exemption that had previously allowed parents whose children were not fully vaccinated to remain eligible for family assistance payments if a health practitioner certified that they were conscientious objectors.
"The good news is that for the first time, all 31 of Australia's [Primary Health Networks] now have immunisation rates for five-year-olds above 90 per cent," Mr Frost said.
"And the gap we see between the areas with the highest and lowest immunisation rates has started to shrink."
The PHNs with the best and worst vaccination rates were both in NSW.
NSW Labor health spokesman Walt Secord said the data bolstered calls for the state government to support tougher anti-vaccination legislation including removing the conscientious objector provisions and introducing a $5500 fine for day care centres that enrol children without a vaccination or medical exemption certificate.
A fully immunised five-year-old has received four doses of diphtheria, tetanus, and whooping cough vaccine, four doses of the polio vaccine, and two doses of the measles, mumps and rubella vaccine
