A measles outbreak that tore through a Melbourne primary school might have been contained faster if schools were forced to keep detailed vaccination records and doctors were quicker to diagnose, health experts say.
Unvaccinated locals helped fuel an outbreak that spread to eight children and two adults within nine weeks in 2014. One of the victims was a baby girl who was too young to be vaccinated.
The source was a seven-year-old boy who brought the virus to Melbourne from overseas, reveals a report examining the outbreak at Essendon North Primary published in the Australian and New Zealand Journal of Public Health.
That first boy passed the virus to his sister. It then jumped to a five-year-old girl who crossed paths with the infected siblings at a shopping centre. The researchers identified 103 sites that had been visited by patients while they were infectious.
That five-year-old girl and her sister took the measles to the Essendon North Primary School, where another three students – two 11-year-old boys and an eight-year-old girl, were infected. Two adult men and a baby girl in the local community also contracted the virus.
The report's authors, led by infectious disease physician Katherine Gibney from the Doherty Institute and Victoria's health department, found that identifying susceptible people exposed during the outbreak was hampered by the quality of the school's immunisation records and delays in medical diagnosis. Of six unvaccinated children at the school, five were infected.
"We have highlighted a number of barriers to controlling this measles outbreak, including delays in diagnosis, notification and identification of susceptible contacts which limited the effectiveness of time-sensitive interventions such as provision of immunoglobulin, vaccine or school exclusion," the researchers wrote.
Schools are required to keep up-to-date vaccination status certificates, known as School Entry Immunisation Status Certificates, for the duration of a child's enrolment, to identify children who were not immunised who were exposed during an outbreak.
Although Essendon North kept records on the number of students for whom a certificate was provided at prep enrolment, during the outbreak it could not provide vaccination histories, including whether students had been immunised, the report states.
But many children were enrolled even without a certificate. In the seven years before the 2014 outbreak, the records indicate that as few as 39 per cent of children in some classes had started school with a certificate of immunisation.
The researchers raised the prospect of a financial penalty for schools who fail to keep vaccination histories. "The addition of a financial penalty for schools non-compliant with this requirement might be an effective way to improve the completeness and usefulness of school-held immunisation records," the report states.
Essendon North principal Scott Mullen said the immunisation records were updated constantly and the school knew which students were not immunised. "Our record keeping is excellent but the children who contracted the measles [in 2014] were children who did not have immunisation," he said.
A Fairfax Media Freedom of Information request for school vaccination rates in April revealed such data was not held by the Department of Education.
"Schools do not interpret the information on [vaccination] certificates, but are obligated to store that information in a way that can be easily accessed in the event of an outbreak of a vaccine-preventable disease that may require exclusion of non-immune children," an information manager wrote at the time.
"Therefore the department can only report on the rate of immunisation status certification presentations, not the actual rate of immunised and non-immunised students."
Health Minister Jill Hennessy said she and Education Minister James Merlino "are working together to see what measures can be put in place to better support schools' management of proof of immunisation certificates so they can take swift action in case of any outbreaks".
Meanwhile, Australian parents remain concerned about giving their children vaccines. A University of Queensland study released on Wednesday that analysed 1342 calls about childhood vaccines to the Medicines Line between 2002 and 2010, found 60 per cent concerned safety fears and 31 per cent were about what was in vaccines.
The measles, mumps and rubella vaccine was the subject of more questions than any other vaccine.
Three-quarters of 23 confirmed school-aged cases of measles since 2014 have been unvaccinated children. Victoria has introduced "no jab, no play" legislation, which requires children to be immunised to attend childcare centres. But no such legislation applies to schools.
"It has been argued that allowing non-medical exemptions is inequitable because exempted children avoid the person risks, however small, associated with vaccination while benefiting from herd immunity that results from high vaccination rates," the report states.
"Conversely there is a danger that compulsory vaccination of children whose parents strongly oppose vaccination could increase the profile of and support for anti-vaccination groups."