Low vax rates raise disease risk
Stubbornly low immunisation rates in parts of New South Wales and Queensland have fuelled concerns that areas of the country are vulnerable to sustained outbreaks of serious diseases including measles and whooping cough.
Figures released by the Council of Australian Governments Reform Council show that although vaccination coverage across most of the country is improving, there are worrying gaps in some areas that threaten to undermine protection against infection.
The report found that infant vaccination rates in areas of NSW where immunisation coverage is low declined in the 12 months to March this year, while Queensland just 82.5 per cent of four-year-olds are fully vaccinated – the lowest proportion in the country.
According to the study, in parts of NSW vaccination rates among children aged between 12 and 15 months have slipped as low as 81.1 per cent, while in South Australia, just 77.1 per cent of Indigenous children in the same age group are fully immunised.
In a more promising result, the report found that vaccination coverage among four-year-olds was at or above 90 per cent in every State or Territory except Queensland (82.5 per cent) and Western Australia (88.9 per cent).
The findings underline concerns that thousands of children are being left vulnerable to deadly diseases by parents who fail to ensure their child’s vaccinations are up to date, or who refuse to have their children immunised.
Figures compiled by the National Health Performance Authority earlier this year found almost 77,000 children nationwide were not fully immunised in 2011-12.
Disturbingly, the Authority identified 32 communities where immunisation rates were 85 per cent in lower in at least one of the one-, two- and five-year-old age groups.
AMA President Dr Steve Hambleton warned at the time that areas of low vaccination coverage left communities vulnerable to sustained outbreaks of serious diseases.
Dr Hambleton said it was no coincidence that several pockets where there were low vaccination rates were also areas where anti-vaccination groups were active, particularly in northern NSW and south-east Queensland.
Underlining the point, the COAG report showed that the Richmond Valley on the northern NSW coast, where the anti-immunisation Australian Vaccination Network is based, had the lowest immunisation rate in the country.
The threat posed by low vaccination coverage has been highlighted by a United States study that found many areas of California hit by a deadly whooping cough outbreak in 2010 had low rates of vaccination.
The outbreak, the worst in the nation for decades, claimed the lives of 10 infants and left more than 9000 ill.
In the seven years leading up to the outbreak, the proportion of parents claiming non-medical exemptions from vaccination for their children more than tripled, from 0.77 per cent to 2.33 per cent.
The study, published in the journal Paediatrics, mapped incidents of whooping cough infections and areas of low immunisation and found that people living in areas where there was cluster of non-medical vaccination exemptions were 20 per cent more likely to contract pertussis that those outside these zones, while those without vaccination were eight times more likely to contract pertussis than those who had been immunised.
This was after researchers had taken into account a range of population characteristics including racial demography, population density, household income, average family size and level of education.
Vaccination has a cumulative effect – the more people in an area who are vaccinated, the less likely it is that an infection will be transmitted through the population. This is particularly important with regard to highly contagious diseases like whooping cough and measles, with estimates that vaccination rates have to reach 94 per cent or higher to ensure herd immunity.
Vaccination expert Paul Offit, of The Children’s Hospital in Philadelphia, told Scientific American the findings showed that “if more and more people choose not to get a vaccine, then you’ll have bigger and bigger outbreaks”.
The AMA has raised concerns that the former Labor Government’s decision to axe the GP Immunisation Incentives Scheme, under which doctors received payments for ensuring more than 90 per cent of their child patients were fully immunised, has helped reduce vaccination coverage.
But, in an effort to boost vaccination rates, the former Health Minister Tanya Plibersek, earlier this year moved to link eligibility for the $726 Family Tax Benefit Part A supplement to full child immunisation – with exemptions only provided on medic al or religious grounds.