The current influenza A virus which caused the death of an 18- month-old boy last week is primarily affecting children and young adults, it has emerged.
Data from the National Virus Reference Laboratory show that 114 respiratory specimens have tested positive for influenza in the last seven weeks.
Of the 111 specimens which were positive for influenza A, 24 cases were in the 0-4 age group, with 15 cases involving children aged 5-14.
Twenty-two specimens came from those aged 15-24, while only two cases were found in those aged 65 or older.
An influenza outbreak usually targets older people causing a rise in hospital admissions as those with chronic bronchitis,asthma and heart problems become acutely unwell.
However, the latest official figures show no reports of increased hospital admissions due to the influenza virus.
As a result, the expected pressure on already overstretched accident and emergency services has yet to materialise.
The National Disease Surveillance Centre, in its latest influenza bulletin, says the detection of influenza in younger age groups is not unexpected given the low levels of flu in circulation for the last two seasons.
"The opportunity for development of immunity (in young age groups) has been limited," it states.
According to the European Influenza Surveillance Scheme, Spain is experiencing widespread flu activity.
Belgium, France and Portugal have reported only "sporadic" cases. In Scotland, a 17-year-old boy died last week from the Fujian-like strain of influenza A which was responsible for the Republic's first death due to flu this year.
Despite the death of the 18- month-old from the south-east region last week, infectious disease experts say such a tragedy is extremely rare.
Most children will make a complete recovery from the virus currently in circulation. Parents of those in the "at-risk" groups are encouraged to have them vaccinated as soon as possible.
Meanwhile the Minister of State for Health, Mr Ivor Callely, has called on the the entire population regardless of age to get flu jabs now to prevent a national epidemic.
He said there were vaccines and if people availed of them then attempts could be made to ensure that as few as possible would be affected. In particular he would encourage all parents to consider getting their children vaccinated in the interest of giving them protection.
The State purchased half a million vaccines which are provided for free. People without medical cards have to pay doctors to administer the jab.