The Minister for Health has encouraged all those at risk of contracting influenza, particularly the over 65s, to go their GPS for immunisation.
Mr Martin said flu vaccines have now been distributed to health boards and doctors throughout the country, where they are available free of charge to all medical card holders.
A total of half a million doses of the vaccine will be distributed by the end of next year.
The minister said those in the "at risk" category include the elderly, those suffering from chronic heart, lung or kidney disease and those with a suppressed immune system.
He said those patients deemed at risk but not in possession of a medical card can get the vaccine for free from health boards, although their GP may charge them to administer it.
All health care workers have also been advised to be immunised.
According to World Health Organisation figures, between 10 and 20 per cent of the global population can be affected by an epidemic of influenza. Between three and five million people suffer serious illness and up to 500,000 people die each year as a result.
