Ms Gill was rushed to Wollongong Hospital in May 2022 with meningococcal disease after she became so unwell she asked her father to call for an ambulance.

The then 18-year-old from Woonona was at work when she noticed she had a headache and was sensitive to noise and light.

Ms Gill, who rarely became unwell, put it down to feeling rundown after an extended holiday with a friend.

But her symptoms continued: she developed a stiff neck, became nauseous, her headache worsened, and she eventually vomited and passed out.

The next day, Ms Gill said, things were "really, really bad" and she told her dad she needed help immediately.

But the thought of invasive meningococcal disease, a rare but potentially deadly illness, was not in their minds.

"We kind of just thought that I had the flu or something... But as soon as the paramedics came inside, they said, 'You've got symptoms of meningitis, we need to take you to the hospital to check you out'," Ms Gill said.

She is sharing her story as Meningitis Centre Australia and health experts urge people to ensure they know the signs and symptoms of invasive meningococcal disease.

Children under two and young people aged 15 to 24 most at risk and while cases usually peak in winter and early spring, they can occur any time; so far this year there have been 26 nationally.

In 2023 there was a 13 per cent increase in the number of cases on the previous year.

Ms Gill did not experience the tell-tale rash many associate with meningococcal disease bar "a couple of red dots" on her arm, but did suffer many of the other early warning signs.

These can be similar to flu-like illness and include fever, headache, neck stiffness, joint pain, a dislike of bright lights, and nausea and vomiting.

Ms Gill continued to deteriorate as she arrived at hospital and ended up spending several days receiving treatment before she could return home.

"[Doctors] basically told me and my parents [dad Sam and mum Katrina] that if we'd been half an hour later, it would have ended a lot worse," she said.

Up to 10 per cent of people who contract invasive meningococcal disease will die, and one in five may develop long-term disability.

Ms Gill felt "so lucky" that both paramedics and doctors recognised her illness and acted so quickly, meaning she came out of the ordeal alive and without permanent disability.

However, she does suffer worse and more frequent headaches than before her illness, tinnitus, and pain in her ears in really loud environments.

The 20-year-old urges people to become familiar with the signs and symptoms of meningococcal disease.

"If you have any of them, even if it's minuscule, it's important to get it checked anyway because it can happen to anyone," she said.

Meningococcal bacteria is spread in drops of fluid from the nose and throat via coughing and sneezing.

Meningitis Centre Australia chief executive officer Karen Quick said people should practise good hygiene by handwashing, coughing or sneezing into your elbow and discarding used tissues correctly to prevent the spread.