After her diagnosis, Lily was told by doctors at Sydney's St Vincent's Hospital that she could have been dead within 30 minutes if she'd ignored her symptoms.
"I am just so lucky I lived three minutes away from the hospital because the doctors told me later that I was only about 30 minutes away from that being it for me," she told Fairfax.
"If I'd waited any longer I probably wouldn't have made it."
Lily, who still suffers from renal and adrenal failure, spent eight days in intensive care, and a total of three weeks in hospital. But she credits her mum for saving her life.
"Thankfully mum had a sixth sense," she said. "I think that's what saved me, that fast response."
The disease destroyed Lily's kidneys, and she currently spends five hours each day on dialysis. Her sister, Grace, will be donating a kidney in two weeks' time.
Lily O'Connell (pictured, left) was enjoying Christmas day with her family last December until she fell very ill and was urgently rushed to hospital. Photo / Facebook
Despite being vaccinated for Meningococcal C, she hadn't received the injection for the W strain.
At a press conference on Sunday, NSW Premier Gladys Berejiklian announced a meningococcal vaccination program for school students in years 10 and 11 will be rolled out across the state in a bid to immunise the community against the disease.
More than 200,000 students have been vaccinated against multiple strains of meningococcal since 2017 in a A$17 million program.
The state-funded program includes the less common W strain because it has an eight per cent mortality rate — twice as high as other meningococcal strains — and diagnoses are on the rise.
The W strain became a concern for the state's health authorities after diagnoses quadrupled between 2014 and 2016.
Ms O'Connell (pictured, left) is lucky to be alive but she still suffers from renal and adrenal failure. She has to spend five hours on dialysis every alternate day. Photo / Facebook
NSW chief health officer Kerry Chant said adolescents were being targeted by the program because schools are an effective way to immunise high numbers of an at-risk group.
The vaccine is also available for purchase for the wider community and Dr Chant urged people to remain vigilant for symptoms as spring usually brings an increase in meningococcal cases.
"If you experience symptoms including a sudden onset of fever, headache, nausea, vomiting, neck stiffness, joint pain or rash of red-purple spots, go straight to your nearest emergency department to seek help," Dr Chant said.
