Two people test positive for meningococcal after Splendour in the Grass

People who attended Splendour in the Grass have been asked to monitor for symptoms of meningococcal.

NSW Health issued an alert on Friday night after two people who attended the music festival tested positive for the disease.

Anyone who attended the event at North Byron Parklands from July 21 to 24 should be alert to symptoms and "act immediately if they appear".

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One of the cases was a man in his 40s who died from the disease.

"His infection was identified following his death and notified to NSW Health yesterday," the authority said.

Dr Jeremy McAnulty from NSW Health said early intervention can be lifesaving.

"Onset of meningococcal disease symptoms can appear suddenly and become very serious very quickly," McAnulty said.

"If you suspect meningococcal disease, don't wait for the rash – see a doctor immediately."

Meningococcal disease can be fatal if left untreated.

Symptoms include:

• Severe and unexplained limb pain
• Difficulty waking up
• High-pitched crying in babies
• Severe headache
• Upset by bright lights
• Stiff neck
• Red and purple rash which doesn't disappear when pressed with a glass

"While it is a well-known symptom of meningococcal disease, the rash does not always occur, or may present late in the illness," McAnulty added.

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"If symptoms rapidly worsen, or if your child is very unwell, call Triple Zero (000) or go straight to your nearest emergency department."

NSW Health said while the disease is rare, up to one in 10 cases die and four in 10 infections result in permanent disabilities.

There have been 15 cases of meningococcal disease reported in NSW so far this year.

Most Australians are vaccinated for meningococcal as babies.

In July, multiple meningococcal cases were identified in South Australia.

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