DEATH from preventable diseases is falling, but vaccination could still have saved 23 NSW children's lives over a decade.
The NSW Ombudsman's latest Child Death Review Report reveals 504 children died in NSW last year; 294 of them were infants less than a year old.
Sudden infant death syndrome was the biggest killer with 42 babies losing their lives under unexplained circumstances.
Transport accidents claimed 33 child lives, four of them on on off-road areas.
The suicide rate was the highest since 1997, 26 young people took their lives in 2015 with children aged 15-17 the most likely.
Abuse contributed to the deaths of eight children, half of whom were less than two years old.
The report found four of the children killed in circumstances of abuse had a child protection history, including two who were in care when they died.
All but one of the eight abuse deaths happened in a familial context, with most children allegedly killed by a parent or another person living in their home.
Two children died in separate incidents of apparent murder-suicide, the report stated.
The ombudsman also released the National Centre for Immunisation Research and Surveillance's report on child death from vaccine-preventable diseases between 2005 and 2014.
While child deaths caused by vaccine-preventable diseases are now rare, the report found 23 child deaths in NSW between 2005 and 2014 that were considered preventable or potentially preventable by readily available vaccinations.
A further 30 deaths were not considered preventable at the time although 15 would now be covered by vaccines.
The majority of those deaths were due to influenza, meningococcal disease and pneumococcal disease with most deaths in babies under six months of age. Several deaths were due to whooping cough and chickenpox.
NCIRS director Peter McIntyre said the report highlighted the importance of immunisation.
"Immunisation has been successful in dramatically reducing the number of childhood deaths from infectious diseases in Australia," Professor McIntyre said.
Readers seeking support and information can phone Lifeline on 13 11 14 or Suicide Call Back Service on 1300 659 467.
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