'I was taking my sick baby's temperature when a voice in my head told me to act fast.'

It was a quiet Easter Sunday afternoon when I noticed my five-week-old baby son, Hugo, was feeling hot on his forehead, arms, and the back of his neck.

I took his temperature — it was around 38 degrees. For the next couple of hours, I was checking his temp about every 10 minutes, noting the temp and time down on my phone, each one notching up a little bit more, the anxiety building with a new recording.

I was equally frazzled in my hazy state of newborn-inflicted tiredness as I was also juggling the demanding needs of Hugo's two-year-old brother.

When it hit 40 degrees, and he started becoming lethargic, I knew something was seriously wrong.

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Hugo had become listless, his complexion turning noticeably pale. I was now panicking inside, trying to project calm as "the mother" (funny how we do that, isn't it?) unsure of what this all meant. He was still breastfeeding, which was somewhat reassuring.

I vividly remember the conversation I had with my husband (former AFL player and now CEO of Sydney Swans, Tom Harley) in our toy-littered lounge room.

As a parent of two kids (today three!), I have learnt to trust my gut feeling about my child's health — you know deep down when something isn't right.

At that moment, that voice inside told me we had to act fast. So Tom and I rushed Hugo to the hospital. 

The next few hours were a blur — I was oscillating between panic, exhaustion and despair — as doctors came and went for a series of rapid assessments and tests.

Tom took our eldest home around midnight and our baby and I were transferred to the infectious disease ward. That night, still in gym clothes, I sat upright, hardly sleeping, clinging to him and never once putting him into the cot in the corner.

The next morning, we were moved to an isolation room with too many windows, which made me feel even more vulnerable. 

Doctors confirmed a diagnosis of invasive meningococcal disease (IMD). 

The only thing I knew about meningococcal disease was from seeing heartbreaking pictures in weekly magazines of kids with purple rashes and lost limbs. My knowledge of the disease was pretty limited, other than knowing that it was a serious infection that could result in death.

I will never forget the hospital shower. The handheld shower nozzle that dribbled water like a beachside tap, the coloured speckles, like 100s & 1000s, circling the top of the cubicle.

The showers were my lifeline, really — time and space to regather my thoughts, to make sense of why this had happened to us, and an escape from the misery of that ward and the other parents pacing the halls.

The sobering reality was, as the doctors reassured me, that the one thing that potentially saved Hugo's life — and perhaps also saved him from any serious future complications — was getting him to the hospital quickly.

We acted fast, and I've since learnt this is crucial to this disease.

IMD, or meningococcal disease, is a rare bacterial infection. While most people infected will survive and recover, this potentially devastating infection can progress rapidly and lead to serious disability in about one in five people. Although meningococcal disease can occur at any age, infants, small children, adolescents, and young adults between 15–24 years old are at most risk.

I wish I had known more about meningococcal disease before our ordeal, and I hope that no other parent will have to experience what we did with Hugo — I actually lived through one of my worst nightmares.

Sure, as I said, I knew about the severe symptoms like the notorious purple rash, but I wasn't aware that initial signs could actually mimic a common cold — headache, fever, extreme fatigue, lack of appetite.

Yes, this can all sound confusing, and perhaps I was also a little confused when I was pacing the loungeroom on that dreaded Easter Sunday, too. But I am glad that we acted quickly in the end. In hindsight, I think, having this knowledge beforehand would have given me more confidence to do so immediately.

It's only now I appreciate how fast meningococcal disease can progress, and I cannot stress enough the importance of knowing the symptoms and understanding the protective measures. (A good thing to discuss with your doctor as it could save your life or that of someone you love.)

After an agonising seven-day hospital stay, Hugo was fortunately discharged (on my birthday!) without any long-term complications from the meningococcal disease.

Today, he is a vibrant nine-year-old and you'll always find him in a Sydney Swans' jersey with a footy tucked under his arm. But I've since met other parents who have lost their children to this harrowing disease. Yes, up to one in 10 infected may die.

So, parents, trust your intuition, really listen to that voice inside you, because you do know best. You know your child better than anyone. If something does not feel or look right, do not hesitate to seek medical attention ASAP.

Want to read more about kids' health? Read these stories next:

• 'To the mums with kids who are constantly sick, I see you.'

• 'I am a nutritionist and mum of 3. Here's how I make sure my kids are eating enough nutrients.'

• The 6 best things parents can do for their kid's mental health, according to a psychologist.

Feature image: Supplied.