Parents and GPs in Britain were today urged today not to mistake meningitis for swine flu as children return to school.
The two illnesses can be easily mixed up because they have similar symptoms, including aches and pains and cold hands and feet.
Cases of meningitis typically rise in the autumn - the same time experts have predicted a surge in the number of cases of swine flu.
Schools and universities going back means people are in close proximity - making it easy for viruses to spread - and the flu tends to thrive in the cooler months.
At least two people are already known to have died from meningitis after mistakenly being diagnosed with swine flu.
Today, Steve Dayman, chief executive of the charity Meningitis UK, said parents should "trust their instincts" and watch out for the disease, which can kill in under four hours.
He lost his own son Spencer to meningitis in 1982, when he was just 14 months old.
"Meningitis occurs throughout the year but very shortly we will see the number of cases going up," Mr Dayman said. "It's very difficult for GPs to identify meningitis in its early stages because it's very similar to flu - with symptoms such as cold hands and feet and aching limbs."
He said a pin prick rash that can turn into purple bruising is a classic sign of a meningococcal meningitis and requires urgent attention. But he said parents should be on their guard even before this happens and seek medical attention if their child appears to deteriorate rapidly.
Children under five are most at risk from meningitis, followed by teenagers and students.
"The issue with children is that there is a rapid deterioration in their condition - within a matter of hours," Mr Dayman said. "I think it's important for parents of children to contact their GP if they feel concerned - meningitis should be a consideration.
"It's all very well GPs saying 'give them Calpol' but that could mean it becomes too late. Once meningitis has established itself and the bacteria is in the bloodstream, it multiplies rapidly and there is no time for delay. "This is about both parents and GPs working together - it's better to be safe than sorry."
Jasvir Kaur Gill (48), from Leicester, died in August from meningitis after being told she had swine flu. She was advised to take Tamiflu after a telephone diagnosis, but suffered a heart attack 12 hours later and was taken to hospital.
In the same month two-year-old Georgia Keeling developed a rash, bruising and a high fever at home. A paramedic diagnosed the toddler with swine flu and told her parents to give her Tamiflu and put her to bed, but she died hours later from suspected meningitis.
Gemma Drury (17), from Chesterfield, was also diagnosed with swine flu but then later treated for meningitis.
PA